Dissertations / Theses on the topic 'ST elevation acute myocardial infarction (STEMI)'

Introduction: Computed electrocardiographic imaging (CEI) is a method that uses ST- segment deviations from the 12-lead electrocardiogram (ECG) and has been tested on a small number of patients.Aim: To extend the testing material of the CEI method and deduce a threshold using ECGs recorded pre- and during acute occlusion. The performance of the CEI and ST elevation myocardial infarction (STEMI) criteria will be compared. Method: Two CEI images were generated from each of 99 patients before and during complete occlusion in the left anterior descending (LAD), right coronary artery (RCA) and left circumflex coronary artery (LCx). Result: The sensitivity and specificity of STEMI criteria was 61% and 96% respectively for the whole occlusion group. The sensitivities and specificities were 74 %, 97% (LAD); 60%, 94% (RCA); 35%, 100% (LCx) respectively, for STEMI criteria. A threshold of 998 units was deduced from the CEI method. Conclusion: The CEI method has similar diagnostic performance of an occlusion as STEMI criteria.

More people die of cardiovascular disease in Australia than from any other condition. Acute Coronary Syndrome (ACS) is the acute event of the chronic condition coronary heart disease (CHD) represents a continuing spectrum of three conditions and can be divided into unstable angina, non ST elevation myocardial infarction (NSTEMI) and ST elevation myocardial infarction (STEMI). Patients’ symptoms in all three conditions are self managed by the first line medication sublingual glycerine trinitrate (SLGTN). The aim of management of ACS is to minimise symptoms and improve quality of life (QOL). Education of this complex medication such as recommended route, timing, side effects, prophylactic use and response to emergency when symptoms are not relieved are essential for the person to be able to effectively self administer the medication. Nitrates such as SLGTN have different biovariabilities and pharmokinetic properties which can have potent adverse effects such as vasodilatation if not taken correctly. Patients self-manage and prevent angina symptoms using SLGTN and rest when they are home; therefore it is essential that they have adequate knowledge of SLGTN and its use. However previous studies have reported patients have poor knowledge of SLGTN and appropriate symptom management.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Nursing and Midwifery
Griffith Health
Full Text

Introduction: Acute coronary syndromes, including ST-elevation myocardial infarction (STEMI), are a leading cause of morbidity and mortality worldwide. Existing research shows that prehospital care provided by emergency medical services (EMS) can significantly improve outcomes. However, EMS remains grossly underutilised in Abu Dhabi despite a well-established presence. Objectives: In this three-part quantitative, observational study, we sought to (1) assess physicians' perceptions of, and recommendations for, utilization and improvement of EMS, (2) assess patients' awareness of EMS, mode of transport use in decision to seek care and reasons for their decision, and (3) establish if in the current study setting, mode of transport used has implications for in hospital adverse events, as well as short and long term clinical outcomes. The goal was to investigate both physicians' and patients' perceptions of prehospital STEMI care, as well as to assess the clinical correlates of the mode of transport in a patient's decision to seek care. Methods: We conducted the study in three phases. Phase 1: At four government-operated hospitals in Abu Dhabi, we administered surveys to a convenience sample of physicians involved in care of patients with acute coronary syndromes to measure (a) likelihood of recommending EMS, (b) satisfaction with EMS, (c) likelihood of using EMS for self or family, and (d) recommendations for prehospital care of acute coronary syndromes. Phase 2: We gathered mode of transport data from a purposive, non-random sample of 587 consecutive patients with STEMI over an 18-month period and conducted structured follow-up interviews to assess their perceptions of EMS. We conducted analysis to determine whether mode of transport was related to demographic variables. Phase 3: We collected medical records from patient participants and conducted structured follow-up interviews at 1, 6 and 12 months post discharge. We conducted chi square difference testing to determine the relationships among mode of transport, treatment times, and short- and long-term clinical outcomes. Variables included treatment times and associated outcomes. Results: Physician participants (n = 106) were most supportive of prehospital 12-lead ECG for STEMI, but indicated low satisfaction with existing EMS services in Abu Dhabi. Among STEMI patient participants (n = 587), EMS was underutilized in Abu Dhabi; over half (55%) of patients did not know the phone number to contact EMS, and only 14.7% used EMS in their decision to seek care. EMS-transported patients were more likely to receive timely treatment (door-todiagnostic ECG time, door-to-balloon time) and had lower incidence of mortality compared to privately-transported patients. Conclusions: These findings suggest a need to raise public awareness of EMS and its importance for coronary symptoms in Abu Dhabi. Broader application of prehospital ECG, including prehospital activation of cardiac catheterization labs, bypassing non-interventional cardiology centres, and admission directly to facilities that provide these services without initial admission to the emergency department, could help improve physicians' perceptions of EMS and outcomes for patients with STEMI.

Myocardial infarction is a leading cause of morbidity and mortality in the developed world. Cardiovascular magnetic resonance (CMR) is an imaging technique that provides non-invasive tissue characterisation of the myocardium. CMR can, therefore, quantify myocardial infarct characteristics in vivo. This aim of this work is to investigate the CMR parameters used to assess and quantify injury following myocardial infarction. The research questions in this thesis are: • How reliable are the CMR parameters found in myocardial infarction? • Can newer sequences impact on the reliability of the assessment of myocardial oedema? • Are existing sequences available for infarct size measurement interchangable? • How does a functional measure of microvascular dysfunction relate to microvascular obstruction identified on CMR? • What can new T1 and T2 mapping sequences contribute to the assessment of myocardial infarction by CMR? CMR is increasingly being used to quantify surrogate endpoints used in myocardial infarction studies. In Chapter 4, pilot work identified that the reproducibility of these end points can vary depending on the expertise of the observer. Chapter 5 determined the most reliable method available for quantifying myocardial · oedema and myocardial infarction was manual contouring. This technique was then used in Chapter 7 to establish the repeatability of CMR parameters used as surrogate endpoints in clinical trials. Chapter 7 identified that the least reproducible CMR parameter measured in acute myocardial infarction was myocardial oedema. Chapter 8 sought to address this issue by evaluating 4 sequences to identify and quantitate myocardial oedema. Of these, a new T2 mapping sequence was the most reproducible for quantitating myocardial oedema. New mapping sequences, both Tl and T2 mapping were further evaluated in Chapter 11 to investigate a cut off value for T2 value in oedematous myocardium following acute myocardial infarction. Chapter 11 also established that infarct characteristics affect the T2 value in affected myocardium. The association between native Tl and T2 mapping and between the extracellular volume and myocardial oedema was also determined. Chapter 7 also highlighted that quantification of myocardial infarction could be improved. Single shot steady state free precession (SS -SSFP) late gadolinium enhancement imaging was assessed against the standard inversion recovery gradient echo sequences in Chapter 9. Although the identification of myocardial infarction was acceptable with the SS-SSFP, quantification was suboptimal with this sequence and therefore should not be used for quantification of infarct size. Despite restoration of flow to the epicardial infarct related artery following acute myocardial infarction, flow is not necessarily optimal in the microvasculature. Chapter 10 provides an in vivo functional insight into microvascular obstruction (MVO) identified on CMR following ST segment elevation myocardial infarction (STEM!) using an invasive measure (the index of microcirculatory resistanceIMR) at the time of primary angioplasty. There is a good association between the IMR and MVO on CMR

The objectives of this thesis are to describe door-to-reperfusion therapy wait times in ST-elevation myocardial infarction (STEMI) at selected hospitals in Quebec, and to identify factors associated with prolonged wait times. We undertook an observational study of patients with STEMI who received reperfusion therapy, at 17 hospitals in Quebec in 2003. Door-to-reperfusion therapy wait times were available for 1,189 of 1,432 patients for patients who received reperfusion therapy. The median door-to-reperfusion therapy wait times were 32 minutes for patients who received fibrinolytic therapy, and 145 and 109 minutes for patients who underwent primary percutaneous coronary intervention (PCI) with and without inter-hospital transfers, respectively.
We conclude that door-to-reperfusion therapy wait times for STEMI approached recommended times for fibrinolytic therapy, but remained prolonged for primary PCI at these 17 hospitals in 2003. Efforts are needed to reduce door-to-reperfusion therapy wait times and especially wait times to primary PCI, to assure maximum benefits from prompt delivery of reperfusion therapy for patients with STEMI.

We evaluated, in patients with ST-elevation myocardial infarction (STEMI) treated with thrombolytics, admission Troponin T (tnT), ST-segment resolution and admission N-terminal pro-brain natriuretic peptide (NT-proBNP) for early risk stratification as well as time delays and outcome in real life patients according to prehospital or in-hospital thrombolytic treatment. Also, baseline characteristics, treatments and outcome in patients enrolled in the ASSENT-2 trial in Sweden and in patients not enrolled were evaluated.

TnT (n=881) and NT-proBNP (n=782) on admission and ST-resolution at 60 minutes (n=516) in patients from the ASSENT-2 and ASSENT-PLUS trials were analysed. Elevated levels of NT-proBNP and tnT on admission were both independently related to one-year mortality. However, when adding information on ST-resolution (

We investigated consecutive STEMI patients included in the RIKS-HIA registry between 2001 and 2004, if they were ambulance transported and had received prehospital (n=1690) or in-hospital (n=3685) thrombolytic treatment. Prehospital diagnosis and thrombolysis reduced the time to thrombolysis by almost one hour, were associated with better left ventricular function and fewer complications and reduced the adjusted one-year mortality by 30% compared with in-hospital thrombolysis.

Prospective data from the RIKS-HIA registry on STEMI patients treated with thrombolytics were linked to data on trial participants in the ASSENT-2 trial of thrombolytic agents and used for direct comparisons. Patients treated with thrombolytics and not enrolled in a clinical trial at trial hospitals (n=2048) had higher risk characteristics, more early complications and twice as high adjusted one-year mortality compared to those enrolled (n=729). One major reason for the difference in outcome appeared to be the selection of less critically ill patients to the trial.

Background: ST-elevation acute myocardial infarction (STEMI) represents one of the leading causes of death. The time of STEMI onset has a circadian rhythm with a peak during diurnal hours, and the occurrence of STEMI follows a seasonal pattern with a salient peak of cases in the winter months and a marked reduction of cases in the summer months. Scholars investigated the reason behind the winter peak, suggesting that environmental and climatic factors concur in STEMI pathogenesis, but no studies have investigated whether the circadian rhythm is modified with the seasonal pattern, in particular during the summer reduction in STEMI occurrence. Methods and Results: Here, we provide a multiethnic and multination epidemiological study (from both hemispheres at different latitudes, n=2270 cases) that investigates whether the circadian variation of STEMI onset is altered in the summer season. The main finding is that the difference between numbers of diurnal (6:00 to 18:00) and nocturnal (18:00 to 6:00) STEMI is markedly decreased in the summer season, and this is a prodrome of a complex mechanism according to which the circadian rhythm of STEMI time onset seems season dependent. Conclusions: The “summer shift” of STEMI to the nocturnal interval is consistent across different populations, and the sunshine duration (a measure related to cloudiness and solar irradiance) underpins this season-dependent circadian perturbation. Vitamin D, which in our results seems correlated with this summer shift, is also primarily regulated by the sunshine duration, and future studies should investigate their joint role in the mechanisms of STEMI etiogenesis.

BACKGROUND Dual antiplatelet therapy is recommended in patients undergoing primary percutaneous coronary intervention (p-PCI) for ST-segment elevation myocardial infarction (STEMI). In the past few decades, oral antiplatelet agents have proved to significantly reduce the incidence of ischemic events in patients with atherothrombotic diseases. Nevertheless, recurrent ischemic events often occur in patients undergoing stent implantation. High platelets reactivity has been associated with a higher risk for major cardiovascular events in patients with acute coronary syndromes (ACS). Several pre-analytical variables may influence platelet function analysis. The aim of our study was to assess the on-treatment platelet reactivity in peripheral and coronary blood, in a group of patients receiving dual antiplatelet therapy undergoing primary percutaneous coronary intervention (p-PCI) for STEMI. METHODS Eligible patients for the study were considered as consecutively admitted patients to the emergency department of University-Hospital of Padua with a diagnosis of ACS with ST-segment elevation scheduled for an urgent procedure of coronary angioplasty. One hundred nine patients who consecutively underwent p-PCI (males: 72%, females: 28%; mean age: 64±13 years) were enrolled. Before the coronary angioplasty intervention, the patients were treated with dual antiplatelet therapy (aspirin 250mg I.V in association with one another oral thienopyridines; Clopidogrel 300/600mg, Prasugrel 60 mg or Ticagrelor 180 mg) and with anticoagulant therapy (unfractionated heparin 70U/Kg I.V). During the coronary angioplasty intervention two different samples were obtained, one from peripheral artery and the other from coronary blood. The platelet aggregation was studied using the impedance aggregometry Multiplate®, according to manufacturer’s indications. For each patient the values of “Area Under the Curve” (AUC) in ADP-test and ASPI-test were considered, both in the peripheral and in coronary blood. “Low responders of antiplatelet therapy” were considered when an AUC value of ASPI-test or ADP-test greater than or equal to a pre-established cut-off. RESULTS The Multiplate® analysis of ADP-test revealed that mean values were slightly higher in peripheral blood compared to coronary blood (peripheral blood: 41±28 U; coronary blood: 39±28 U), However these values with no statistically significant difference (p=0.68). Likewise, for the ASPI-test; no statistically significant difference between the mean values in the peripheral blood compared to the coronary blood (peripheral blood: 23±4 U; coronary blood: 17±2 U; p=0.06). The percentage of low-responders to ADP-receptor inhibitors was significantly greater than the percentage of low-responders to acetylsalicylic acid at time of primary PCI both in the peripheral and in the coronary blood samples (peripheral ADP-test: 38%; peripheral ASPI-test: 14%; p<0.01, Coronary ADP-test: 36%; coronary ASPI-test: 11%; p<0.01). In peripheral blood, the prevalence of “low Clopidogrel responders” was higher (45%) than that observed for Prasugrel (36%) and Ticagrelor (33%). Similar results were observed in coronary blood, the prevalence of “low Clopidogrel responders” was higher (40%) than that observed for Prasugrel (36%) and Ticagrelor (29%) however these results were with no significant statistical difference (p >0.05). Finally, a positive and statistically significant linear correlation was observed for both ASPI-test and ADP-test in peripheral and coronary blood (r2 0.23, p <0.001 and r2 0.12, p <0.001; respectively). That means; those who are resistant to acetylsalicylic acid tend to be resistant to ADP receptor inhibitors, and vice versa; those who are sensitive to acetylsalicylic acid therapy tend to be sensitive to ADP inhibitor therapy also. Our observed data did not show a correlation between platelet function and clinical outcome both for in-hospital and 1-year clinical outcomes. CONCLUSIONS In this study we observed that the overall platelet reactivity in coronary blood is lower than in peripheral blood, though not statistically significant. This more likely appears to be due to high antiplatelet drugs effect at plaque ulceration/thrombus site, where the hemostatic process is highly active at onset of STEMI. Larger studies are needed for better evaluation of these mechanisms in term of pharmacodynamic, pharmacokinetic and receptor kinetic properties of antiplatelet agents. The other interesting result emerging from data processing is the high incidence (about 30%) of low response to thienopyridine type antiplatelet drugs at the time of primary angioplasty. This result, moreover known for Clopidogrel in addition our results include patients treated with Prasugrel and Ticagrelor also. An explanation of this phenomenon which also involves potent recent drugs, requires careful analysis and further studies. The significant direct correlation between platelet reactivity in peripheral and in coronary blood is still a matter of debate. Larger studies are needed for in-depth assessment of any correlation between on–treatment platelet reactivity measured in coronary blood and clinical outcome.
INTRODUZIONE La doppia terapia antiaggregante (DAPT) è raccomandata in pazienti sottoposti ad intervento di angioplastica coronarica primaria (p-PCI) per infarto miocardico acuto con sopraslivellamento del tratto ST (STEMI). Infatti, il trattamento con farmaci antipiastrinici orali ha dimostrato di ridurre significativamente l'incidenza di eventi ischemici nei pazienti con malattie aterotrombotiche sia in fase acuta che in fase cronica. Tuttavia, spesso si verificano eventi ischemici ricorrenti nei pazienti sottoposti ad angioplastica ed impianto di stent. È stato dimostrato che una delle cause di recidiva ischemica sia l’elevata reattività delle piastrine. Pertanto, lo studio della funzione piastrinica diventa un elemento sempre più importante per valutare questo tipo di pazienti. Diverse variabili pre-analitiche possono influenzare l'analisi della funzione piastrinica. Lo scopo del nostro studio è stato quello di valutare la reattività piastrinica del sangue periferico e coronarico in un gruppo di pazienti trattati con DAPT e sottoposti p-PCI per STEMI. METODI Abbiamo considerato eleggibili allo studio tutti i pazienti consecutivamente giunti in urgenza al Pronto Soccorso dell’Azienda Ospedaliera di Padova con diagnosi di sindrome coronarica acuta con sopraslivellamento del tratto ST per i quali fosse indicata l’esecuzione in urgenza di una procedura di angioplastica coronarica. Sono stati arruolati 109 pazienti (maschi: 72%, femmine: 28%; età media: 64±13 anni). I pazienti arruolati nello studio sono stati trattati, prima di essere sottoposti alla procedura di angioplastica primaria, con doppia terapia antiaggregante (aspirina 250 mg e.v in associazione con uno dei seguenti tre farmaci: Clopidogrel 300/600 mg per os, Prasugrel 60 mg per os o Ticagrelor 180 mg per os) e con terapia anticoagulante (eparina non frazionata 70 U/Kg e.v). Durante la procedura di angioplastica primaria sono stati eseguiti due tipi di prelievo, uno dal sangue arterioso periferico ed uno dal sangue arterioso coronarico. L’aggregazione piastrinica è stata studiata con l’aggregometro Multiplate® secondo le indicazioni fornite dal costruttore. Per ogni paziente sono stati valutati i valori di “Area Under the Curve” (AUC) nell’ADP-test e nell’ASPI-test, ottenuti sul sangue periferico e sul sangue coronarico. “Low responders alla terapia antiaggregante” sono stati definiti quei pazienti con valori di “Area Under Curve” (AUC) all’ASPI test o all’ADP test sono maggiore o uguale a un range prestabilito. RISULTATI Non abbiamo osservato differenza statisticamente significativa tra i valori medi di ADP-test calcolati su sangue periferico e su sangue coronarico. I valori medi delle AUC sono risultati lievemente superiori nel sangue periferico che nel sangue coronarico (sangue periferico: 41±28 U; sangue coronarico: 39±28 U; p=0.68). Allo steso modo, non è stata riscontrata differenza statisticamente significativa tra i valori medi di ASPI-test calcolati su sangue periferico e su sangue coronarico. Anche in questo caso abbiamo osservato valori medi di AUC lievemente superiori nel sangue periferico che nel sangue coronarico (sangue periferico: 23±4 U; sangue coronarico: 17±2 U; p=0.06). Sia nel sangue periferico che nel sangue coronarico la percentuale di pazienti “low responders” al trattamento con inibitori del recettore per l’ADP è risultata essere statisticamente superiore alla percentuale di pazienti “low responders” alla terapia con acido acetilsalicilico al momento dell’angioplastica primaria (ADP-test periferico: 38%; ASPI-test periferico: 14%; p<0.01. ADP-test coronarico: 38%; ASPI-test coronarico: 11%; p<0.01). Nel sangue periferico la prevalenza di "low responders” al Clopidogrel era superiore (45%) a quella osservata rispettivamente per Prasugrel (36%) e Ticagrelor (33%). Risultati simili sono stati osservati nel sangue coronarico. In particolare, la prevalenza di "low responders” al Clopidogrel è stata superiore (40%) rispetto a quella osservata per Prasugrel (36%) e Ticagrelor (29%). Non è stata osservata alcuna differenza significativa (p> 0,05) nella prevalenza dei pazienti con valori di ADP-test superiori al cut-off prestabilito, considerando separatamente le tre diverse tienopiridine. Infine è stata individuata una correlazione lineare statisticamente significativa tra “low responders” all’acido acetilsalicilico e “low responders” agli inibitori del recettore dell’ADP. Questa osservazione indica come i pazienti resistenti al trattamento con acido acetilsalicilico tendono ad essere resistenti anche al trattamento con inibitori del recettore per l’ADP e, viceversa, pazienti “sensibili” alla terapia con acido acetilsalicilico tendono ad essere “sensibili” anche al trattamento con inibitori del recettore per l’ADP. Questi resultati sono stati osservati sia su sangue periferico (r2 0.23, p<0.001) che su sangue coronarico (r2 0.12, p<0.001). I dati che abbiamo osservato non mostrano un’associazione tra funzione piastrinica e outcome clinico nè per quanto riguarda gli “in-hospital outcome” né per quanto riguarda gli outcome a distanza di 1 anno. CONCLUSIONI I dati analizzati ci hanno permesso di dimostrare che la reattività piastrinica nel sangue coronarico era inferiore rispetto a quella osservata nel sangue periferico. Sembrerebbe quindi che, la risposta alla terapia farmacologica con doppia antiaggregante prima della procedura sia maggiore proprio laddove il processo emostatico è più attivo, ossia a livello della placca aterosclerotica sede della formazione del trombo responsabile dell’insorgenza della STEMI. Questo meccanismo necessità di conferma in termini di farmacodinamica, farmacocinetica e di cinetica recettoriale. L’altro dato estremamente interessante emerso dall’elaborazione dei dati è l’elevata incidenza (circa 30%) dei pazienti “low responders” al trattamento con farmaci antiaggreganti di tipo tienopiridinico al momento della angioplastica primaria. Questo risultato, peraltro noto per il Clopidogrel, comprende anche pazienti trattati con Prasugrel e Ticagrelor. Una possibile spiegazione di questo fenomeno, che coinvolge anche i farmaci di “seconda generazione”, necessita di un’attenta analisi. Abbiamo infine osservato una significativa correlazione tra reattività piastrinica nel sangue periferico e nel coronario. I nostri risultati, che alla luce dei limiti del nostro lavoro devono considerarsi come preliminari, necessitano di essere confermati su casistiche più numerose soprattutto per quanto riguarda la correlazione tra “on-treatment platelet reactivity” misurata nel sangue coronarico e outcomes clinici.

Background Reperfusion is the mainstay treatment for patients presenting with ST-elevation myocardial infarction (STEMI). Nevertheless, reperfusion itself may exacerbate myocardial injury, a process termed “reperfusion injury”. Post-conditioning (PostC) has been suggested to reduce myocardial damage during primary percutaneous coronary intervention (PPCI), nevertheless clinical experience is limited. Objectives We aimed to review all the known strategies to limit the reperfusion injury; moreover we explored the cardioprotective effect of mechanical postconditioning conducting a randomized trial aimed to evalutate infarct size (IS) at cardiac magnetic resonance (CMR) in STEMI patients treated by PPCI. Methods A total of 78 patients with first STEMI (aged 59±12 years) referred for PPCI, were stratified for STEMI location and randomly assigned to conventional PPCI or PPCI with PostC. All patients, with occluded infarct related artery and no collateral circulation, received abciximab intravenously before PPCI. After reperfusion by effective direct stenting, control subjects underwent no further intervention, while in treated patients PostC was performed within 1 minute of reflow by 4 cycles of 1-minute inflation and 1-minute deflation of the angioplasty balloon. Primary end-point was IS reduction, expressed as percentage of left ventricle mass assessed by delayed enhancement on CMR at 30±10 days after index PPCI. Results All baseline characteristics but diabetes (p=0.06) were balanced between groups. Postconditioning patients trended towards a larger IS compared to those treated by standard PPCI (20±12% vs 14±10%, p=0.054). After exclusion of diabetics, PostC group still showed a trend to larger IS (p=0.116). Major adverse events seem to be more frequent in PostC group irrespective to diabetes status (p=0.053 and p=0.080, respectively). Conclusions This prospective, randomized trial suggests that PostC did not have the expected cardioprotective effect and, on the contrary, it might harm STEMI patients treated by PPCI plus abciximab. (Clinical Trial Registration-unique identifier: NCT01004289).
Razionale dello studio La terapia riperfusiva è la via principale per il trattamento di pazienti che si presentino con infarto miocardico con sopraslivellamento del tratto ST (ST-elevation myocardial infarction, STEMI). Tuttavia, la riperfusione di per sé può esacerbare il danno miocardico, un processo denominato “danno da riperfusione”. Il post-conditioning (PostC) é un processo che sembra possa ridurre il danno miocardico da riperfusione durante angioplastica primaria (primary percutaneous coronary intervention, PPCI), ciò nonostante l’esperienza clinical è limitata. Scopo dello studio Presentare e discutere tutte le strategie note in grado di limitare il danno riperfusivo; inoltre, valutare gli effetti cardioprotettivi del postconditioning ischemico meccanico mediante un trial clinico controllato randomizzato arruolante pazienti con STEMI e inviati a PPCI, con endpoint primario le dimensioni dell’infarto (infarct size, IS) finale alla risonanza magnetica cardiaca (cardiac magnetic resonance, CMR). Metodi Un totale di 78 pazienti con primo STEMI (età 59±12 anni) inviati per PPCI, sono stati stratificati per sede dello STEMI e successivamente randomizzati a PPCI convenzionale o PPCI con PostC. Tutti i pazienti, con arteria responsabile dell’infarto occlusa e assenza di circolo collaterale, hanno ricevuto abciximab endovena prima della PPCI. Successivamente alla riperfusione, avvenuta con tecnica direct stenting, i soggetti di controllo non sono stati sottoposti ad ulteriori interventi, mentre i soggetti nel gruppo PostC hanno rivevuto, entro un minuto dalla riperfusione, 4 cicli di 1 minuto di rigonfiaggio e 1 minuto di sgonfiaggio del pallone usato per l’angioplastica. L’endpoint primario oggetto dello studio, la riduzione dell’IS finale, veniva espresso come percentuale della massa ventricolare sinistra affetta, come possibile riconoscere ad una CMR con mezzo di contrasto eseguita a 30±10 giorni di distanza dalla procedura di PPCI indice. Risultati Tutte le caratteristiche di base, ad eccezione del diabete (p=0.06), risultavano ben bilanciate tra i gruppi di trattamento. I pazienti nel gruppo postconditioning tendevano ad avere un IS maggiore quando paragonati a quelli sottoposti a PPCI convenzionale (20±12% vs 14±10%, p=0.054). Dopo esclusione dei pazienti diabetici, il gruppo di pazienti PostC sembrava ancora associato ad IS finali di maggiori dimensioni (p=0.116). Gli eventi avversi cardiovascolari maggiori sono risultati essere più frequenti nel gruppo PostC, indipendentemente dal loro status diabetico (p=0.053 e p=0.080, rispettivamente). Conclusioni Questo trial clinico randomizzato prospettico suggerisce che il PostC non ha l’effetto cardioprotettivo atteso e, invece, potrebbe pure nuocere a pazienti affetti da STEMI e sottoposti a PPCI ed infuzione di abciximab. (Numero identificativo unico di registrazione del trial al sito clinicaltrial.gov: NCT01004289).

Background: Cardiac Magnetic Resonance (CMR) has utility in the risk stratification of patients post ST elevation myocardial infarction (STEMI). Myocardial strain is theoretically more linked to left ventricular pump function than left ventricular ejection fraction (LVEF). There are a number of CMR strain techniques including bespoke methods such as displacement encoding with stimulated echoes (DENSE) and cine derived methods such as feature-tracking. Whilst cine-derived strain is more appealing for imaging in real-world practice, there are concerns on accuracy, especially on a myocardial segmental level. Deformation-tracking is a new technique based on tissue-tracking from cine imaging which has been developed in our group and is theoretically more accurate at identifying myocardial displacement and shortening than other commercial cine-strain techniques. Hypothesis: Compared with standard methods for imaging heart function, novel strain methods have superior diagnostic and prognostic performance. Objectives: (1) I aimed to compare circumferential strain derived from DENSE, deformation-tracking and feature-tracking in a group of 81 healthy volunteers, and in a group of STEMI patients. I investigated the relationship between strain age and sex in the healthy volunteers. (2) I also investigated the comparative performance of the three strain techniques and LV surrogate outcomes (LVEF, LV end diastolic volume indexed to body surface area, infarct size) as well as composite health outcomes (major adverse cardiac events) at 4 years in the STEMI patients. (3) I investigated the incremental predictive utility of segmental circumferential strain over infarct size to predict segmental functional improvement by wall-motion scoring at 6 months in patients with STEMI, and the influence of infarct characteristics (microvascular obstruction, intra-myocardial haemorrhage) on segmental circumferential strain at 6 months. (4) I investigated the utility of feature-tracking derived global longitudinal strain in this STEMI group. (5) Finally, I performed a de-novo study implementing a new DENSE technique in a group of STEMI patients and compared deformation-tracking and feature-tracking against this new technique. Methods: 1. Healthy Volunteers Study: 81 participants underwent multi-parametric CMR at 1.5T. 2. STEMI population 1: 324 patients underwent a similar multi-parametric CMR at 3 days and 295 at 6 months post STEMI. Composite health outcomes that are pathophysiologically linked to STEMI were collected by an independent team. 3. STEMI population 2: 50 patients underwent a multi-parametric CMR at 1 day and 6 months post STEMI. This protocol included the new 2D-Spiral DENSE sequence. The imaging analyses were performed using standardised methods. Health outcomes were analysed and adjudicated by an independent team blinded to the rest of the study. Statistical analyses were carried out under the supervision of a biostatistician. Results: The main findings of this thesis are: 1. Deformation-tracking performed well when compared with a reference method (DENSE) in a large group of healthy volunteers. The advantage of utilising a cine-strain derived method is that this would obviate the need for bespoke strain sequences being acquired, limiting the total duration of an CMR scan, and making strain more accessible in the clinical setting. 2. Global circumferential strain with DENSE provides incremental prognostic value over infarct size and pathologies revealed by contrast-enhanced CMR for LV surrogate outcomes. Strain imaging with DENSE has emerging potential as a new reference test for prognostication in patients after an acute STEMI. 3. Global circumferential strain with DENSE provides incremental prognostic value over infarct size and pathologies revealed by contrast-enhanced CMR for MACE. Conclusions: The data presented in this thesis indicate that CMR strain imaging may be clinically useful in the assessment of patients following an acute STEMI. This indicates that strain should be more widely used in clinical studies as both global and segmental strain provide incremental utility over more commonly used markers of prognosis for global and regional LV function, as well as major adverse cardiac events. 2D-Spiral DENSE is a new technique, which I have demonstrated, to be feasible to acquire in STEMI patients and has the potential to investigate LV pump function in more detail than conventional methods.

ST-elevation myocardial infarction (STEMI) management has evolved dramatically, with improved pharmacological treatment, rapid achievement of reperfusion with percutaneous coronary intervention (PCI) and advanced secondary prevention programmes, resulting in a decline in morbidity and mortality. However, it is well recognised that myocardial perfusion remains compromised in up to 50% of STEMI patients, despite rapid and successful mechanical revascularisation of the epicardial artery. This occurrence is called the “no-reflow” phenomenon and as a result, a substantial proportion of acute STEMI patients develop chronic cardiac failure, owing to poor microvascular function and myocardial perfusion. Although pathological and clinical observations initially seemed to support the theory that no-reflow was a consequence of microvascular obstruction (predominantly from distal embolisation of athero-thrombotic debris), irreversible microvascular injury and subsequent intramyocardial haemorrhage (IMH) are now also thought to play important factors in this process. T2*-CMR is the reference diagnostic method for imaging myocardial haemorrhage in-vivo, however technical issues have limited T2* imaging in clinical practice. The largest cohort studies of myocardial haemorrhage in STEMI patients to date, have not used T2* CMR, but instead used qualitative T2-weighted imaging methods to detect haemorrhage, which are hampered by image artefact. Because of the different CMR techniques, uncertainties have arisen surrounding the pathophysiology and clinical significance of myocardial haemorrhage, and its relationships with microvascular obstruction (MVO). In some studies, myocardial haemorrhage is associated with adverse remodelling and adverse clinical outcome, however other studies have shown that myocardial haemorrhage does not have prognostic significance beyond MVO. Recent developments in CMR imaging techniques have enabled clinically feasible, rapid parametric mapping, which allows direct determination of myocardial magnetic relaxation times (T1, T2 and T2*). These quantitative, novel mapping methods, address many of the inherent limitations associated with dark blood T2-weighted techniques, for a more objective assessment of the infarct core. The principal aim of this thesis is to define the clinical significance of myocardial haemorrhage using quantitative CMR mapping techniques and to determine whether detection of haemorrhage might improve risk stratification in STEMI survivors. In addition, I aim to characterise the evolution and inter-relationships between IMH and MVO in STEMI survivors to inform and implement targeted therapeutic interventions. Methods (1) Natural history study: We performed a single centre cohort study in 324 reperfused STEMI patients treated predominantly by emergency percutaneous coronary intervention (PCI) (The BHF MR-MI study; Clinicaltrials.gov NCT02072850). The index of microcirculatory resistance (IMR), a prognostically validated invasive microcirculatory biomarker, was measured acutely in the culprit coronary artery at the end of PCI using guidewire based-thermodilution. Infarct zone IMH and MVO were delineated as hypointense zones on T2* mapping CMR (T2* value < 20 ms) and contrast-enhanced-CMR at 1.5 Tesla, respectively, 2 days and 6 months post-MI. T1- and T2-mapping techniques were also used to assess the infarct core and evaluate IMH. (2) Time-course study: 30 patients underwent serial CMR at 4 time-points: < 1 day (4 to 12 hours), 3 days, 10 days and 6-7 months post-reperfusion. Adverse remodelling was defined as an increase in left ventricular end-diastolic volume (LVEDV) ≥ 20% at 6 months. Adverse cardiovascular events were pre-specified and defined according to internationally accepted criteria. All-cause death or heart failure were independently assessed during follow-up blind to other data. (3) Randomised proof-of-concept trial: We hypothesised that brief deferral of stenting after initial reperfusion, associated with the benefits of normal coronary flow and anti-thrombotic therapies, would reduce microvascular injury and increase myocardial salvage. We implemented a randomised proof-of-concept clinical trial of deferred PCI vs. immediate stenting (NCT01717573) (Carrick et al., 2014). In summary, the main findings of this thesis are: • Myocardial haemorrhage (defined by T2* CMR) is an independent predictor of adverse remodelling and all cause death or heart failure in the longer-term post STEMI. • Myocardial hemorrhage occurs in primary and secondary phases within the first 10 days post-MI and is a secondary phenomenon to the initial occurrence of microvascular obstruction. • Myocardial haemorrhage peaked at day 3 post-MI in reperfused STEMI patients, and the temporal changes in oedema may be a secondary process. • A hypointense infarct core on T2-mapping always occurred in the presence of microvascular obstruction and commonly in the absence of myocardial haemorrhage within 12 hours and 3 days post-MI, indicating that the presence of T2-core is more closely associated with microvascular obstruction than myocardial haemorrhage. • Infarct core pathology revealed by T2 (ms) was independently associated with all-cause death or heart failure hospitalisation during longer term follow-up. • Native T1 values (ms) within the infarct core were independently associated with adverse remodelling and adverse clinical outcome and had similar prognostic value when compared to microvascular obstruction. • IMR measured in the culprit coronary artery after reperfusion is more strongly associated with myocardial haemorrhage than microvascular obstruction in STEMI survivors 2 days later. • The proof-of-concept pilot deferred stenting trial showed that compared with standard of care with immediate stenting, brief deferral of stenting after initial reperfusion; reduced angiographic no-reflow, tended to reduce IMH and MVO, and increased myocardial salvage. The findings of this PhD are novel and have important clinical implications. Firstly, we found that myocardial haemorrhage occurs commonly and is a biomarker for prognostication in STEMI survivors. Secondly, IMR adds early prognostic information at the time of emergency reperfusion and has potential to stratify patients at risk of IMH for more intensive therapy. Thirdly, our results confirm that infarct pathologies are evolving dynamically and potentially, may be amenable to targeted therapeutic interventions. Finally, IMR has the potential to stratify STEMI patients acutely and deferred PCI is a simple intervention that could be practice changing, if the planned Phase 3 trial DEFER-STEMI confirms the hypothesis.

Cardiovascular disease is the leading cause of death worldwide and ischemic heart disease is the most common manifestation. Despite improved outcomes during the last decades, patients with acute coronary syndromes (ACS) are still at substantial risk of recurrent ischemic events and mortality. The aims of this thesis were to investigate the effect of the novel antiplatelet agent ticagrelor versus clopidogrel in patients with non-ST-elevation ACS (NSTE-ACS), overall and in relation to initial revascularization, and to explore this effect in relation to cardiac biomarkers. The impact of timing of revascularization in non-ST-elevation myocardial infarction (NSTEMI) was also studied, by assessing risk of mortality and recurrent myocardial infarction in relation to delay of percutaneous coronary intervention (PCI) in a nation-wide cohort. Finally, a novel clinical prediction model based on angiographic findings, biomarkers, and clinical characteristics was developed to estimate risk of ischemic events after performed revascularization. Ticagrelor treatment compared with clopidogrel was associated with a reduction in the composite endpoint of cardiovascular death/myocardial infarction/stroke and mortality alone, without any increase in overall major bleeding, but increased non-CABG-related major bleeding. The effect of ticagrelor over clopidogrel was consistent independent of initial revascularization. Elevated high-sensitivity cardiac troponin-T predicted benefit of ticagrelor over clopidogrel, while no difference between treatments was detected at normal levels. In patients with NSTEMI, PCI treatment within two days after hospital admission was associated with lower risk of all-cause death and recurrent myocardial infarction compared with delayed PCI. The new clinical prediction model included the following variables: prior vascular disease, extent of coronary artery disease, level of N-terminal pro-B-type natriuretic peptide and estimated glomerular filtration rate; and showed good discriminatory ability for the risk prediction of cardiovascular death/myocardial infarction/stroke and cardiovascular death alone. In conclusion, these results show that ticagrelor reduces the risk of recurrent ischemic events and mortality in patients with NSTE-ACS when compared with clopidogrel, and this effect seems independent of performed revascularization. The results also indicate that biomarkers could be used to select patients who would benefit most from more intense platelet inhibition. Furthermore, early PCI in NSTEMI seems to be associated with improved outcome. Finally, the novel clinical prediction model based only on four variables showed good discriminatory ability, which makes it a potentially effective and simple tool for tailored treatment based on individual risk of recurrent events.

Background: Cardiovascular Magnetic Resonance (CMR) comprehensively assesses myocardial injury in ST-segment elevation myocardial infarction (STEMI). Complete revascularization (CR) may improve outcomes compared to an infarct-related artery (IRA)-only strategy in patients with multivessel disease at primary percutaneous coronary intervention (PPCI). However, CR could cause additional non-IRA infarcts. Objectives: To determine optimal techniques for quantifying infarct characteristics and myocardial strain in STEMI. To assess whether in-hospital CR was associated with increased myocardial injury compared to an IRA-only strategy in the CvLPRIT-CMR substudy. To investigate differences in myocardial injury associated with staged and immediate in-hospital CR. To assess CMR predictors of segmental myocardial functional recovery post-STEMI. Methods: Multicentre PROBE-design trial in STEMI patients with multivessel disease and ≤12 hours symptom duration. Patients were randomized to IRA-only PCI or in-hospital CR. Contrast-enhanced CMR was performed at 3 days post-PPCI and stress CMR at 9 months. The pre-specified primary endpoint was infarct size (IS) on acute CMR. Accuracy, feasibility and observer variability for semi-automated CMR methods of quantifying infarct size and area-at-risk (AAR) were assessed. Strain quantification using Feature Tracking and tagging was assessed. Functional recovery in dysfunctional segments was assessed at follow-up CMR on wall-motion scoring. Results: 205 of 296 patients in the main trial participated in CvLPRIT-CMR and 203 (105 IRA, 98 CR) completed acute CMR. There was a strong trend towards reduced AAR in the CR group (p=0.06). Total IS was similar with IRA-only PCI: 13.5% (6.2-21.9%) and CR: 12.6% (7.2-22.6) of LV mass, p=0.57. The CR group had an increased incidence of non-IRA MI at acute CMR (22/98 vs. 11/105, P=0.02). There was no difference in total IS or ischemic burden between the groups at follow-up CMR. Full-width half-maximum, Otsu's Automated Thresholding and Feature Tracking were used for IS, AAR and strain analysis. Immediate CR was associated with reduced IS. Conclusions: In-hospital CR for multivessel disease in STEMI leads to a small increase in CMR non-IRA MI but total IS was not different from an lRA-only PCI strategy. The comparable ischaemic burden in the groups suggests that the similarly improved medium-term clinical outcomes seen in the CvLPRIT, PRAMI and DANAMI-3- PRIMULTI studies are unlikely to be ischaemia-driven and instead may result from stabilization of unstable plaques and improved collateral flow to the ischaemic AAR.

Introduction Prior to percutaneous coronary intervention (PCI) guidelines recommend that patients with ST- elevation myocardial infarction (STEMI) receive dual antiplatelet therapy (DAPT) consisting of P2Y12 inhibition and acetylsalicylic acid (aspirin). However, in rare occasions, patients admitted with STEMI as preliminary diagnosis require acute thoracic surgery and oral P2Y12 inhibitors increases the bleeding risk over several hours. Cangrelor is an intravenous reversible P2Y12 antagonist with normal platelet function returning within 60 minutes and might therefore be an attractive alternative to oral P2Y12 inhibition.Aim Firstly, to quantify P2Y12 pre-treatment with ticagrelor in patients undergoing acute thoracic surgery and the mortality and morbidity rate associated with DAPT prior to surgery. Secondly, to estimate cost-benefit differences between cangrelor and ticagrelor pre-treatment.Material and Methods A descriptive cohort study using retrospective data. The inclusion criteria were patients undergoing acute thoracic surgery (≤ 24 hours) between January 2015 and December 2017, in the catchment area of Örebro University Hospital. Patients were stratified into groups depending on whether they had received pre-treatment with DAPT or not before surgery. Statistical analyses were made in SPSS and Excel.Results A total of 50 patients were included. 8 patients received DAPT before surgery. There was no mortality in patients receiving DAPT but TIMI major bleeding was more frequent compared to the group with no pre-treatment. The DAPT group required numerically more units of platelets and plasma, however the result was not significant. Direct treatment costs for ticagrelor was 20.14 SEK (the dosage is 2 tablets) and cangrelor was 3 059 SEK.Conclusions DAPT pre-treatment with ticagrelor was not associated with increased mortality but TIMI major bleeding was more frequent compared to the group with no pre-treatment. Direct treatment costs with cangrelor was higher compared to ticagrelor treatment. Further studies, with larger study samples, are needed to investigate complications associated with P2Y12 pre-treatment in patients undergoing acute thoracic surgery.

Background: Acute hyperglycemia (AH) is common in ST-elevation myocardial infarction (STEMI) and predicts outcomes. AH is a more powerful prognostic predictor in patients without diabetes mellitus (DM) than with DM, emphasizing the role of an acute glucose rise compared to chronic elevations. Moreover, AH may exacerbate, thorough mitochondrial dysfunction, infarct size (IS). We investigated the association between AH and chronic glycemia, considered separately or in combination, with mitochondrial injury and myocardial IS in STEMI patients with or without DM. Methods: We measured admission serum glucose (AH), cytochrome c and mitochondrial DNA levels (mitochondrial biomarkers), and estimated chronic glucose in all patients. We calculated the acute on chronic (A/C) glycemic ratio. The primary endpoint was IS at cardiac magnetic resonance. The composite of in hospital mortality, acute-pulmonary-edema, and shock was the secondary endpoint. Results: 100 STEMI patients with DM and 100 without were included. IS was 25gr and 19gr and the secondary endpoint occurred in 21% and 8% of patients with and without DM, respectively (p=0.02 and p=0.01, respectively). The A/C ratio only significantly correlated with cytochrome c and mitochondrial DNA levels in DM patients. However, at reclassification analyses, A/C glycemic ratio showed the best prognostic power in predicting the primary and secondary endpoints as compared to AH in DM (net-reclassification-index 28% and 31%, respectively) but not in non DM patients (net-reclassification-index 1% and 2%, respectively). In DM patients, A/C glycemic ratio, but not AH, significantly predicted 1-year mortality, after adjustment for major confounders. 4 Conclusions: In STEMI patients with DM, A/C glycemic ratio seems to be a better predictor of IS and in-hospital and 1-year outcome than AH. This study highlights the prognostic role of A/C ratio, its impact on mitochondrial impairment and outcomes, and may pave the way to interventional trials targeting AH according to A/C ratio in DM patients with STEMI.

This thesis addresses different aspects of antithrombotic strategies in patients with acute coronary syndrome, mainly in ST elevation acute myocardial infarction (STEMI) patients treated with percutaneous coronary intervention (PCI), regarding their efficacy and safety during the acute phase as well as their appropriateness and impact on long-term outcomes.

碩士
國立臺灣大學
公共衛生碩士學位學程
106
Background: In Taiwan, approximately 20,000 people a year experienced acute myocardial infarction (AMI) and the incidence rate is increasing year by year. Some patients suffering from this condition cannot be saved. The medical expenses and social and economic losses caused by the worsening or death from the disease are enormous. In recent years, with the development of information technology, some cities in Taiwan have implemented pre-hospital electrocardiogram systems (PHECG) to detect suspected myocardial infarction patients as early as possible and notify emergency departments to prepare for emergent catheterization before patients arrived at the hospital. At present, there is no research focusing on the effects of using PHECG on medical quality, medical care utilization and economic assessment. Objective: The aim of this study was to compare the differences in medical quality and medical care utilization between ST-segment elevation myocardial infarction (STEMI) patients who used PHECG and those who didn''t. And to analyze the cost effectiveness and economic assessment of using PHECG. Methods: This study used the cardiac catheterization database of a medical center in southern Taiwan. We enrolled patients who used PHECG and were found to be suffering from STEMI and those who did not use PHECG from January 2012 to July 2017. We compared the difference of the door-to-balloon time (D2B time), the Ischemic-to-balloon time (I2B time), the rate of D2B time less than the 90mins, the death rate, the number of ICU days, the number of hospital days, the costs of health insurance payments and the costs of actual medical expenses. The chi-square test, Mann-Whitney U test, Logistic regression and Linear regression were used to compare the difference in outcomes and costs. Incremental cost-effectiveness ratio (ICER) was calculated from the perspectives of society, the city government, and National Health Insurance Administration (NHIA) with regard to the cost per life saved and per life year saved. Result: There were 68 patients of this study, including PHECG group of 26 and Non-PHECG group of 42 people. There were no differences in the baseline characteristics between these two groups. The mean D2B time was 47.2 minutes in the intervention group, 86.6 minutes in the control group (p< 0.001). The rate of D2B time less than the 90mins was 25 (96.1%) for the intervention group and 31(73.8%) for the control group (p = 0.022). In addition, there was no statistically significant difference in the in-hospital mortality rate, the I2B time, the number of ICU days, the number of hospital days, the costs of health insurance payments and the costs of actual medical expenses in the two groups. Conclusion: This study found that the use of PHECG group for the D2B time and the D2B time has less than 90 minutes had better outcomes, and also lower medical costs than Non-PHECG group. Therefore, the use of PHECG was a dominant modality in patients with STEMI. It is estimated that a total reduction of 14.2 deaths annually will be achieved in Kaohsiung City. The results of economic evaluation show that in terms of incremental cost for per live saves, the ICER for the perspectives of the society, the city government, and the NHIA were NT$477,234, 75,905, and 24,135 respectively. In terms of the incremental cost per life year saved, the ICER for the perspectives of the society, the city government, and the NHIA were NT$30,969, 4,926, and 1,566 respectively.

Background: Glycated hemoglobin is the indicator of long-term diabetes control and a value below 7 percent is recommended by the American Diabetes Association (ADA) to reduce cardiovascular complications. Diabetic patients have a two- to four-fold risk of cardiovascular disease and approximately two-thirds of diabetic patients die as a result of cardiovascular complications. Three large prospective randomized controlled long-term trials within the last decade reported no significant reduction in cardiovascular complications in type 2 diabetic patients by intensive glycemic control. To the author's knowledge, no known retrospective studies have examined the association between mean serial glycated hemoglobin and coronary atherosclerosis (CA) or acute coronary syndromes (ACS). Objective: This study was designed to determine the association between mean serial glycated hemoglobin with incident CA or ACS in type 2 diabetic patients after controlling for age, gender, hypertension, low density lipoprotein cholesterol (LDL-C), microalbuminuria, aspirin use, statin use, insulin use, tobacco use, and body mass index (BMI). Methods: The study was a retrospective cohort database analysis using the Austin Travis County CommUnityCare[trademark] clinics' electronic medical record for the time period between October 1, 2004 and September 30, 2009. The primary outcome of the study was the incidence of CA or ACS and the primary independent variable was glycated hemoglobin (<7% vs. [greater than or equal to]7%). The study subjects included type 2 diabetic patients aged 30 to 80 years with at least one glycated hemoglobin value per year for a minimum of two consecutive years. Study subjects were excluded if CA or ACS occurred within six months of the index date (i.e., first glycated hemoglobin). Logistic regression analysis was used to address the study objective. Results: Overall, 3069 subjects met the study inclusion criteria with a mean follow-up period of approximately two years. Two percent (N=62) of the subjects had incident CA or ACS. After controlling for age, gender, hypertension diagnosis, LDL-C, microalbuminuria, aspirin use, statin use, insulin use, tobacco use and BMI, there was no significant association (OR=1.026, 95% CI=0.589-1.785, p=0.9289) between mean serial glycated hemoglobin and the incident diagnosis of CA or ACS. Increasing age (OR=1.051, 95% CI=1.025-1.077, p<0.0001), male gender (OR=1.855, 95% CI=1.105-3.115, p=0.0195) and normal weight (normal or underweight compared to obese: OR=0.122, 95% CI=0.017-0.895, p=0.0438) were significantly associated with incident CA or ACS. Conclusions: Mean serial glycated hemoglobin (comparing [greater than or equal to]7% to <7%) was not significantly associated with CA or ACS over a mean follow-up period of approximately two years. Until more evidence becomes available, clinicians and diabetic patients should target glycated hemoglobin level below or close to 7 percent as recommended by the ADA soon after diagnosis while concomitantly controlling nonglycemic risk factors of cardiovascular disease (statin use, aspirin use, blood pressure control, smoking cessation and life style modification), to reduce their long-term risk of incident CA or ACS.
text

碩士
國立清華大學
電機工程學系
105
Acute myocardial infarction (AMI) onset when an interruption in the supply of myocardial oxygen and nutrients occurs and causes damage to the myocardium. The infarct area may hinder the normal contraction of the myocardium, increasing the loading of healthy parts of the heart, and even cause death of more cardiac cell. Finally, it may evolve into heart failure or other more severe conditions. Therefore, we want to find some parameters that can be used as a predictor of cardiac deterioration. In the thesis, according to the blocking blood vessel, AMI patients are divided into right coronary artery (RCA) group and left anterior descending (LAD) group. Every patient recorded 24 hours ECG during the acute stage (within 72 hours after AMI), 3 months post-MI (90 ± 14 days after AMI), 6 months (180 ± 28 days after AMI), and chronic phase (1 year). At each stage, we only extracted four hours data with waking period in heart rate variability (HRV) analysis, and then used Mann-Whitney U test to assess the difference in HRV parameters between AMI patients and the controls. The HRV results shown that there is a difference between AMI patients and the control subjects. At the chronic phase, the parameters of frequency domain and multiscale entropy (MSE) curve display the difference between AMI patients and the controls. At the acute stage, the long-term fractal scaling exponent (α2) in detrended fluctuation analysis (DFA) of AMI patients is significantly lower than that of the controls. The results also proved that the nonlinear methods of HRV such as MSE and DFA can provide some information that traditional parameters not showed. Since the HRV parameters, which had a significant difference between RCA group and the controls, are slightly different to LAD group, it confirms that the effect on the heart caused by the blocking of dissimilar blood vessels is not the same. Therefore, RCA group and LAD group should not be mixed into one group. Moreover, we want to find out some available parameters from acute stage ECG signal to predict the probability of AMI recurrence, heart failure or death. However, none of the patients died or developed heart failure during 1 year of follow-up. Therefore, we divided patients into two groups according to the left ventricular ejection fraction (LVEF) after AMI attack one year. The group with lower LVEF was regarded as a group of AMI patients who have a good status of the heart, and the other group was regarded as a group of AMI patients who have a better status of the heart. The HRV parameters, the standard deviation of all normal to normal intervals (sdNN), low frequency (LF), the slope of MSE curve in short scale (slope1-5) and DFA α2 were significantly different at the acute stage between two groups. Creatinine kinase -MB (CKMB), which is obtained from blood tests and related with the damaged area of the heart, also had a significant difference between two groups. In order to compare the discrimination ability of those parameters and CKMB, we used receiver operating characteristic (ROC) curve analysis. LF has the best discriminatory power (AUC=0.8051), the second one is slope1-5 (AUC=0.7721), and the third one is CKMB (AUC=0.739). Then we used LF, slope1-5 and CKMB to establish a logistic regression model, and the AUC of this model is 0.8235. It indicated that combining CKMB and HRV parameters can really enhance the discrimination rate.

碩士
國立臺灣大學
健康政策與管理研究所
103
Background and Objectives: The ST-segment elevation myocardial infarction (STEMI) patients need rapid primary percutaneous coronary intervention (PCI) to get good outcomes. The aim of this study is to assess the effect of implementing team resource management (TRM) in managing STEMI patients in Taoyuan General Hospital. Methods: This study includes STEMI patients, who underwent primary PCI in Taoyuan General Hospital. These patients are divided into two study groups: one group consists of 109 STEMI patients, who were admitted to our hospital during the pre-TRM period (from January, 2009 to December, 2010) and the other group consists of 97 STEMI patients, who were admitted to our hospital during the post-TPM period (from February, 2011 to January, 2013). We analyze the DTB times and clinical outcomes of both groups. Results: The mean DTB time of post-TRM group is significantly shorter than that of the pre-TRM group (82.6±14.5 vs 107±27 min; p<0.001). Four intervals of DTB time (door to ECG, ECG to CV doctor, CV doctor to PCI team, and ER to cath room) are all significantly shorter after the implementation of TRM. The clinical outcomes (days of ICU stay, total admission days, and major adverse cardiac events) are not different between these two groups. However, patients with longer DTB time (> 90 min) have higher MACE rate. Conclusion: Implementation of TRM at our institution significantly reduces DTB times of STEMI patients. However, the clinical outcomes are not improved by TRM.

ABSTRACT: Introduction: Despite achieving normal epicardial coronary artery flow after primary percutaneous coronary intervention (P-PCI), a significant proportion of patients with acute ST elevation myocardial infarction has a poorer outcome because of microvascular coronary damage and/or dysfunction. Endothelial dysfunction may play a role in this microvascular coronary damage after STEMI, and its evaluation by peripheral arterial tonometry may be useful to predict the extent of microvascular coronary damage and the extent of myocardial infarction. Objectives: To evaluate the relation of early peripheral endothelial dysfunction, as measured by the reactive hyperemia index (RHI, obtained by peripheral arterial tonometry) and the index of microcirculatory resistance (IMR) immediately after P-PCI and to access the relation between RHI and IMR values and: 1) the extent of myocardial infarct evaluated by contrast enhanced cardiac magnetic resonance (ceCMR) and troponin release; 2) the extent of microvascular obstruction (MVO), evaluated by ceCMR and by other available indirect indicators; 3) late (3 months) left ventricular remodelling, measured by echocardiography. Methods: Observational, prospective cohort study. Patients with a first STEMI successfully treated with P-PCI, hemodynamically stable and without contra-indications for adenosine administration were included. After successful P-PCI, IMR was determined, using a pressure-wire. RHI was evaluated acutely and after 24 hours, using EndoPAT; endothelial dysfunction was defined as RHI<1.67, and RHI was also analysed by tertiles. Corrected TIMI frame count (cTFC) and TIMI myocardial perfusion grade (TMBG) were evaluated at the end of the procedure. Blood tests for cardiac biomarkers were collected on admission and on scheduled intervals during the first 48 hours. ECGs were recorded before and immediately after P-PCI and at 90 and 180 minutes, for ST resolution evaluation. Left ventricular global and regional function were evaluated by echocardiography at baseline and at 3 months. ceCMR was performed on the 7-8th day post-MI. Results: 60 patients were included (48 males, mean age 59.6±12.7 years). In the first acute RHI values were higher than expected (mean 2.15±0.58) suggesting important technical pitfalls; no relation was found between this acute RHI and any of the infarct extent or microvascular obstruction indicators. Mean RHI values measured at 24 hours were 1.87±0.60. Patients with an RHI<1.67 on this second evaluation tended to have higher IMR (median 40.5 IQR 54.4 vs. median 22.0 IQR 26.0, p=0.09), worse ST resolution, worse angiographic (cTFC and TMPG) results and had more MVO in the ceCMR (54.1% vs. 11.1%, p=0.03). They also had significantly larger infarcts as evaluated by peal TnI (p=0.024) and AUC TnI (p=0.012) and a tendency to have larger infarcts in the ceCMR. Left ventricular ejection fraction (LVEF) was lower and wall motion score index (WMSI) was higher in the first Echocardiogram in these patients. IMR median values were 24 (IQR 33). IMR strongly correlated with MVO on the ceCMR (r=0.91, p<0.0001; ROC curve 0.723, CI95% 0.500-0.896, p=0.018). Patients with IMR>24 had significantly worse ST resolution and angiographic indicators of microvascular dysfunction. IMR also correlated with infarct mass (r=0.70, p<0.001) and salvage mass (r=0.35, p=0.014) in the ceCMR. Patients with IMR>24 had significantly higher peak (p=0.013) and AUC (p=0.003) TnI. LVEF improved significantly only in patients with IMR<24 (p=0.01). IMR independent predictors were age, glucose and HbA1c. Conclusions: RHI measured in the acute phase of STEMI after P-PCI seems to be unfeasible. RHI measured 24h after the P-PCI is feasible and predicts infarct size and MVO, confirming endothelial dysfunction as an important mechanism in microvascular dysfunction in STEM patients. IMR is strongly correlated with MVO and predicts both infarct size and LV remodelling.
RESUMO: Introdução: Apesar da normalização do fluxo coronário epicárdico após intervenção coronária percutânea primária (ICP-P), uma proporção significativa dos doentes com enfarte agudo do miocárdio com elevação do segmento ST (EAMcST) têm piores resultados clínicos devido ao desenvolvimento de lesão ou disfunção microvascular coronária. A disfunção endotelial provavelmente desempenha um papel nesta lesão microvascular coronária e a sua avaliação por tonometria arterial periférica poderá ser útil para prever a extensão da lesão microvascular e a extensão do enfarte. Objectivos: Avaliar a relação da disfunção endotelial periférica precoce, avaliada pelo índice de hiperémia reactiva (IHR, obtido por tonometria arterial periférica) com o índice de resistência da microcirculação (IRM), medido imediatamente após a ICP-P e estimar a relação entre o IHR e o IRM e, 1) a extensão do enfarte, avaliada por ressonância magnética cardíaca com contraste (RMCc) e pela curva de libertação de Troponina I; 2) a extensão da obstrução microvascular (OMV), avaliada por RMCc e por outros indicadores indirectos; 3) a remodelagem ventricular esquerda tardia (aos 3 meses), avaliada por ecocardiografia. Métodos. Estudo observacional, prospectivo, de coorte. Foram incluídos doentes com um primeiro EAMcST, tratados com sucesso por ICP-P, hemodinamicamente estáveis e sem contra-indicações para administração de adenosina. Depois da ICP-P, o IRM foi medido usando um fio de pressão. O IHR foi avaliado na fase aguda e novamente 24 horas depois da ICP-P. A disfunção endotelial foi definida como um IHR<1,67 e o IHR foi também analisado por tercis. Os indicadores angiográficos de reperfusão (contagem corrigida de frames e grau de perfusão miocárdica TIMI) foram avaliados no final da ICP-P. Foram colhidas análises na admissão e em horários definidos nas primeiras 48 horas para avaliação da Troponina I. Antes, imediatamente após e 90 e 180 minutos depois da ICP-P foram registados electrocardiogramas, para avaliação da resolução das alterações do segmento ST. A função ventricular esquerda global e segmentar foi avaliada por ecocardiografia após a ICP-P e aos 3 meses. A RCMc foi efectuada ao 7-8º dia após o EAMcST. Resultados: Foram incluídos 60 doentes (48 homens, idade media 59,6±12,7 anos). Na primeira avaliação, os valores de IHR foram muito superiores ao esperado (média 2,15±0,58), provavelmente por erros técnicos incontornáveis, não se relacionando com nenhum dos indicadores de extensão do enfarte ou de OMV. Na segunda avaliação, às 24h, os valores médios de IRH foram 1,87±0,60. Os doentes com IRH <1,67 tiveram tendencialmente valores mais elevados de IRM (mediana 40,5 IIQ 54,4 vs. mediana 22,0 IIQ 26,0, p=0,09), pior resolução do segmento ST, piores resultados nos indicadores angiográficos de OMV e maior probabilidade de ter OMV na RMNc (54,1% vs. 11,1%, p=0,03). Também tiveram enfartes de maior dimensão na avaliação pela TnI I máxima (p=0,004) e pela área sob a curva de TnI (p= 0,012). A fracção de ejecção do ventrículo esquerdo (FEVE) foi menor e o score de motilidade segmentar (SMS) maior nestes doentes. A mediana do IRM foi 24 (IIQ 33). O IRM correlacionou-se fortemente com a OMV avaliada na RMNc (r=0.91, p<0.001; curva ROC 0,723, IC95% 0,500-0,896, p=0,018). Nos doentes com IRM >24, a resolução do ST foi significativamente menor e os indicadores angiográficos de reperfusão foram significativamente piores. O IRM também se correlacionou com a massa de enfarte (r=0,70, p<0,001) e a massa de miocárdio salvo (r=0,35, p=0,014) na RMCc. Os doentes com IRM>24 tiveram valores significativamente mais elevados de TnI máxima (p=0,013) e ASC de TnI (p=0,003). A FEVE melhorou de forma significativa apenas nos doentes com IMR<24 (p=0,01). Os preditores independentes do IRH foram a idade, a glicemia na admissão e a HbA1c na admissão. Conclusões: Não parece ser possível avaliar de forma fidedigna o IHR na fase aguda do EAMcST após ICP-P. O IHR medido 24h após a ICP-P é mensurável de forma adequada e prevê a dimensão do enfarte e da OMV, confirmando a disfunção endotelial como um mecanismo importante na disfunção microvascular em doentes com EAMcST. O IRM correlaciona-se fortemente com a OMV e permite prever a dimensão do enfarte e o risco de remodelagem ventricular esquerda.

A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, in fulfillment of the degree of Master of Science in Medicine, 2014
The earliest possible initiation of reperfusion therapy is necessary to reduce morbidity and mortality from acute STEMI. Therefore improving the time to thrombolysis where percutaneous coronary interventional facilities are limited or do not exist is critical. The most effective system would integrate three key components to deliver continuous patient care, including: 1) from time of call for help through to emergency response; 2) transportation to and admission to hospital; 3) assessment and initiation of thrombolytic therapy. The purpose of this prospective study is: to develop a chest pain awareness education programme appropriate for the South African context; to assess safe initiation of thrombolytic therapy by emergency care practitioners for STEMI; and to compare the performance of emergency care practitioner thrombolysis with historical control data.

University of Technology Sydney. Faculty of Health.
[Background] Health-related quality of life (HRQOL) is an important measure of patient outcome following primary percutaneous coronary intervention (PPCI) for an ST-Elevation myocardial infarction (STEMI). The assessment of HRQOL quantifies patient perceptions of the impact of an acute, unanticipated cardiac event on their survival and normal function. Despite international recognition and recommendations supporting HRQOL as a vital measure of cardiovascular health status, HRQOL remains under-reported and not routinely implemented in PPCI care. Field triage patients who are fast-tracked to PPCI have less ischaemic time delays than routine Emergency Department (ED) admissions but their HRQOL and cardiac rehabilitation (CR) attendance patterns have not been investigated. [Aims] This study aims to examine HRQOL outcomes of STEMI patients and to identify the key factors that influence recovery and CR attendance at 4 weeks and 6 months after PPCI. [Method] Clinical and HRQOL data was collected and compared for age categories, divided at 60 and 70 years separately; the cut-off age of 70 years used for this thesis. The cut-off for older age at 60 years was used for the systematic review based on the global standard set by the World Health Organisation (World Health Organization, 2002). The age cut-off was changed to 70 years for the thesis study as it is more representative of older people in developed countries such as Australia. The timing of follow-up at 4 weeks and 6 months was chosen based on published evidence that improvements in HRQOL post-PPCI reached a plateau at 6 months, after which, no significant differences occurred. A prospective cohort study was conducted with repeated measures for all consecutive STEMI patients (n=246) comprised of 194 males and 52 females. All were treated by PPCI after ED or Field Triage admissions in two metropolitan hospitals, the Royal North Shore and North Shore Private Hospitals. Additional analyses included HRQOL in the subgroup of Field Triage patients and determination of CR participation at 4 weeks and 6 months. [Results] Age, length of hospitalisation, gender, partnership status and number of stents deployed were independent predictors of HRQOL after STEMI and PPCI. Participants aged ≥ 70 years achieved better cardiac-related HRQOL and mental health from angina relief despite physical limitations. Older age, longer hospitalization, hypertension and recurrent angina were associated with poorer HRQOL for field triage patients. Despite a high referral rate (96%, n=233), CR attendance was sub-optimal (36-54%, n=89-132). A total of 221 patients attended CR; men and patients who received post-discharge support were more likely to attend. [Recommendations] There is a need to integrate HRQOL measurement into PPCI care to ensure post-discharge support is directed at those who need it most. Older people and women were identified in this research as having lower HRQOL and attendance at CR. Important factors that negatively impact on HRQOL such as recurrent angina and longer hospitalization need to be considered in cardiovascular health-care delivery and risk management of acute STEMI cohorts. [Conclusion] The HRQOL for all ages improves from 4 weeks to 6 months after PPCI including field triage patients. Older age, longer hospitalization and female gender are common predictors of poorer HRQOL and lower CR attendance, constituting areas requiring future research focus.

碩士
中山醫學大學
醫學研究所
100
Objective: Patients with acute ST-elevation myocardial infarction may have persistent impairment of microvascular blood flow even after successful primary percutaneous coronary intervention ( PCI ). Distal embolization is a possible mechanism of microvascular dysfunction and impaired myocardial perfusion. There has been increasing interest in adjunctive mechanical thrombectomy to improve outcomes in primary PCI. The aim of the present report is to study the role of AngioJet thrombectomy in primary PCI for acute ST-elevation myocardial infarction . Method and Materials: This is a retrospective cohort study. Patients presented with acute ST-elevation myocardial infarction and received primary PCI in ChangHua Christian Hospital between Jan. 2003 and Oct. 2007 were enrolled. Totally 313 patients were included, 219 patients are in the AngioJet group and the other 94 patients are in the control group. The baseline characteristics, angiographic findings and 6-months survival in these two groups were recorded. Results: Patients in the AngioJet group have more male, cardiac enzymes elevation and angiographically visible thrombus. The angiographic findings showed that 94.1% in the AngioJet group have TIMI 3 flow after primary PCI, but only 80.9% in the control group have the same TIMI 3 flow. Besides, we also find the similar MBG flow between two groups. MBG 3 flow was achieved in 56.2% of the AngioJet group and 39% of the control group. The 6-months survival did not show significant difference between groups ( 93.2% versus 91.5% ). Conclusion and Suggestion: AngioJet thrombectomy in primary PCI for patients with acute ST-elevation MI can improve TIMI flow and MBG flow. But it remains to be established weather the device improves outcomes. The current evidence does not support the routine use of the AngioJet system in primary PCI. But in selected patients with large burden of thrombus, it still can provide clinical benefit as an adjunct to primary PCI.

碩士
國立成功大學
高階管理碩士在職專班(EMBA)
105
Acute ST elevation myocardial infarction is mainly caused by occlusion of the coronary artery. It is associated with high mortality and is one of the leading causes of mortality all over the world. Nowadays, percutaneous coronary intervention is the treatment of choice for acute ST elevation myocardial infarction, which efficiently lowers the patient mortality. The most important treatment concept of acute ST elevation myocardial infarction is to re-perfuse the occluded coronary artery as soon as possible. The prognosis of patients is improved by shortening the door-to-balloon time. Almost all the acute ST elevation myocardial infarction patients are treated with percutaneous coronary intervention in our study medical center, located in South Taiwan. Internal analysis reveals a great variation in the door-to-balloon time. The objective of this study is to find out the factors associated with this variation. From 1st January 2013 to 31st December 2016, patients with acute ST elevation myocardial infarction treated with percutaneous coronary intervention are enrolled. The associations of variables with door-to-balloon time are checked by relevant statistical methods. We find that the door-to-balloon time is less if the triage for patient is a cardiovascular system disease or if the patients are transferred from outside hospitals. By contrast, the door-to-balloon time is greater if the door-to-electrocardiogram time is greater or if the patients come to hospital at off-hours. In conclusion, shortening the door-to-electrocardiogram time and facilitating the rapid activation of percutaneous coronary intervention team, especially at off-hours, may be the ways to shorten the door-to-balloon time in this medical center.

碩士
中山醫學大學
醫學研究所
103
Abstract Objective : Previous studies have shown patients with ST-segment elevation myocardial infarction (STEMI) who received primary percutaneous coronary intervention (pPCI) during office hours versus off-hours. Those studies reported door to balloon time increase during off-hours and had worse clinical outcome. In Taiwan, door to balloon time was no different between office hours and off-hours. We evaluated the mortality rate between office-hours and off-hours in Taiwan. Methods and Materials: This study population comprised 253 STEMI patients treated with primary PCI in a medical center during 2012–2014. We evaluate the relationship between treatment during office-hours (Monday-Friday, 8.00 am-6.00 pm) versus off-hours (Monday-Friday, 6.00 pm-8.00 pm, Saturday and Sunday) and the incidence of all-cause mortality at 30-day . After the data collection, all samples were processed and analyzed by multiple analysis of variance, hazard ratio, Cox proportional hazard model and Kaplan-Meier curve, by SPSS for windows 18.0. Results: Total of 101 patients (40%) were treated during office-hours and 152 patients(60%) during off-hours. With the exception of diabetes mellitus, smoking, low-density lipoprotein, use of glycoprotein IIb/IIIa antagonists, no major differences in baseline characteristics were observed between the groups. Patients with STEMI presenting during off-hours who receive percutaneous coronary intervention time (door to balloon time) were similar to office-hours (72.62±26.81 minutes vs 79.46±35.60 p=0.102). Mortality at 30-day follow-up was similar in patients treated during office-hours and those treated during off-hours (10% vs 6% p=0.151)(log-rank p=0.226). Higher BMI (HR 0.88 p=0.035), Smoking (HR 0.115 p=0.04), higher LDL (HR 0.984　p=0.022), Drug-eluting stent (HR 0.357　p=0.048) will decrease mortality risk. Female (HR 3.656 p=0.005), renal insufficiency (HR 4.740 p=0.001), uremia (HR 5.544 p=0.022), higher age (HR 1.066 p<0.001) will increase mortality risk. After adjustment with age, sex, smoking and LDL by multivariable Cox proportional hazards regression, no smoking is a independent factor (adjusted HR 4.950 p=0.046). Conclusion and Suggestion: In acute ST elevation myocardial Infarction patients who treated during off-hours in a medical center in Taiwan, primary PCI provides similar door to balloon time and survival as patients who were treated during office hours.

碩士
中山醫學大學
醫學研究所
101
Objective:To examine the angiographic scoring system (SYNTAX, SYNergy between PCI with TAXus and cardiac surgery) in association with clinical events of renal insufficiency patients with acute ST-segment elevation myocardial infarction reperfused with primary percutaneous coronary intervention. Background:Data of SYNTAX scores in association with clinical outcomes of acute ST-segment elevation myocardial infarction in renal insufficiency patients who underwent primary percutaneous coronary intervention, however, remains limited. Materials and methods:We retrospectively analyzed the medical records and coronary angiographic films of 505 acute ST-segment elevation myocardial infarction patient who has underwent primary percutaneous coronary intervention, from June 2002 to December 2009, at the cardiovascular center of Ming-Sheng General Hospital, at North Taiwan. Finally, 485 cases were enrolled in our study; patients were divided into two groups, non-renal insufficiency group(331 patients) and renal insufficiency group(154 patients).The clinical outcomes in our study is 180-D major adverse cardiovascular event post primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction. Results:In this article, SYNTAX score shows independent predictive value for outcomes of renal insufficiency patients undergoing percutaneous coronary intervention for acute ST-segment elevation myocardial infarction. In multivariate analyzes, SYNTAX score ≥ 12.5 was independently associated with 180-Day major adverse cardiovascular events for both non-renal insufficiency ( hazard ratio: 4.30, 95% CI, 1.21~ 15.30, p-value < 0.05 ) and renal insufficiency patients( hazard ratio: 4.06, 95% CI, 1.44~11.47, p-value < 0.05 )who underwent primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction. Conclusion:For renal insufficiency patients who presented with acute ST-segment elevation myocardial infarction and underwent primary percutaneous coronary intervention；SYNTAX score provided significant prognostic values for 180-D clinical outcomes.

碩士
長庚大學
商管專業學院碩士學位學程在職專班醫務管理組
101
Cardiovascular disease is one of the major leading causes of death in Taiwan. Acute ST-segment elevation myocardial infarction (STEMI) carries high and rapid mortality among cardiovascular disease. STEMI is usually caused by acute thrombus formation on a ruptured atherosclerotic plaque in a coronary artery. The evidence of medicine has approved the rapid reperfusion therapy can significantly reduce the mortality. Patients with STEMI should receive primary percutaneous coronary intervention (PCI) with door-to-balloon (D2B) time within 90 minutes. Some strategies were suggested worldwide before, but the short message method to shorten D2B time is the first time. The study is quasi-experimental quantitative design for research. Considering the medical environmental homogeneity and the interference of time factor, the data were collected retrograde among two major regional hospitals in Keelung city. The intervention hospital performed short message to activate the cath team. The control hospital performed ordinary consult system by telephone. According the time of short message intervention, the 141 patients were consecutive collected. The major findings were as follows: the cath team arriving time was longest and had biggest variation among the regular and off time before group call message intervention. After intervention, the cath team arriving time decreased from 60 min to 30 min, the success rate of D2B<90 min increased from 51% to 90%, D2B time decreased from 96 min to 70 min, and 30 days all cause mortality decreased from 8.9% to 0. The medical costs of the administration decreased from 149,811 to 83,354 dollars. According the study results, the short message service intervention in primary PCI may shorten D2B time, decrease Troponin I level, reduce medical costs and 30 days mortality. The study offers a simple and effective method to improve the quality of care for STEMI therapy.

Με δεδομένο το γεγονός ότι η αιμοπεταλιακή αναστολή είναι θεμελιώδους σημασίας σε ασθενείς με οξύ έμφραγμα του μυοκαρδίου με ανάσπαση του ST τμήματος που υποβάλλονται σε πρωτογενή αγγειοπλαστική (PPCI), η αναγνώριση παραγόντων που σχετίζονται με την εμφάνιση στην οξεία φάση υψηλής αντιδραστικότητας των αιμοπεταλίων (HTPR) παρά τη θεραπεία με κλοπιδογρέλη μπορεί να είναι σημαντική. Σε ασθενείς με STEMI και επακόλουθη PPCI εκτιμήθηκε η αιμοπεταλιακή αντιδραστικότητα 2 ώρες μετά τη φόρτιση με 600mg κλοπιδογρέλης με τη χρήση της παρακλίνιας μεθόδου VerifyNow P2Y12. Το όριο ≥235 P2Y12 μονάδων αντιδραστικότητας (PRU) θεωρήθηκε ενδεικτικό HTPR. Από τους 92 ασθενείς με STEMI, 63 (68,5%) βρέθηκαν να έχουν υψηλή αιμοπεταλιακή αντιδραστικότητα στις 2 ώρεςμετά τη φόρτιση. Οι ασθενείς με την υψηλή αντιδραστικότητα είχαν λάβει ‘πρώιμη φόρτιση’ με κλοπιδογρέλη πιο συχνά, είχαν χαμηλότερη τιμή αιμοσφαιρίνης και έτειναν να έχουν επηρεασμένη νεφρική λειτουργία σε σε σχέση με αυτούς που είχαν ικανοποιητική απάντηση στην κλοπιδογρέλη. Στην πολυπαραγοντική ανάλυση, η ‘πρώιμη φόρτιση’ και η κάθαρση κρεατινίνης <60ml/min είχαν ανεξάρτητη συσχέτιση με υψηλότερο κίνδυνο εμφάνισης HTPR (σχετικός κίνδυνος [RR]=1,55 95% διάστημα εμπιστοσύνης [CI]:1,11-2,17 P=0,01 και RR=1,31 95% CI: 1,008-1,71 P=0,04 αντίστοιχα). Επομένως σε ασθενείς με STEMI που υποβάλλονται σε PPCI, η ‘πρώιμη φόρτιση’ με κλοπιδογρέλη και η επηρεασμένη νεφρική λειτουργία αποτελούν ανεξάρτητους προβλεπτικούς παράγοντες εμφάνισης υψηλής υπολειπόμενης αντιδραστικότητας των αιμοπεταλίων (εκτιμούμενης με τη μεθοδο VerifyNow) 2 ώρες μετά την αρχική φόρτιση με 600mg κλοπιδογρέλης
Given that platelet inhibition is crucial when ST-elevation myocardial infarction (STEMI) patients undergo primary PCI (PPCI), the identification of factors associated with early high on-treatment platelet reactivity may be important. Consecutive STEMI patients admitted for PPCI were considered for platelet reactivity assessment 2 h after loading with 600 mg clopidogrel using the VerifyNow point-of-care P2Y12 assay. A cut-off of ≥235 P2Y12 reaction units indicated high on-treatment platelet reactivity. Out of 92 STEMI patients, 63 (68.5%) were found to have high on-treatment platelet reactivity. Patients with high on-treatment platelet reactivity had received upstream clopidogrel loading more frequently, had lower admission hemoglobin and tended to have an impaired renal function compared to those with an adequate response to clopidogrel. On multivariate analysis, upstream clopidogrel loading and creatinine clearance <60 ml/min were independently associated with higher risk for high on-treatment platelet reactivity (relative risk [RR]=1.55, 95% confidence interval [CI]: 1.11–2.17, P=0.01; RR=1.31, 95% CI: 1.008–1.71, P=0.04, respectively). In patients with STEMI undergoing PPCI, use of upstream clopidogrel and impaired renal function independently predict high on-treatment platelet reactivity assessed as early as 2 h following 600 mg of clopidogrel loading dose on point-of-care P2Y12 function assay.

碩士
國立陽明大學
急重症醫學研究所
99
Background/ Aim: Current guidelines recommend >75% of patients with an ST-elevation myocardial infarction (STEMI) to receive primary percutaneous coronary interventions (PPCI) within 90 minutes. The goal has been hardly achievable, so we have conducted a 2-year before-and-after study to determine the impact of implementation of emergency department (ED) tele-electrocardiography (tele-ECG) triage and interventional cardiologist activation of the infarct team at the door-to-balloon time (D2BT) and the proportion of patients undergoing PPCI within 90 minutes since arrival. Methods and Results: A total of 105 consecutive patients with acute STEMI (mean aged 62±13 years, 82% male) were studied: 54 before and 51 after the change in protocol. The 51patients in the tele-ECG group received tele-ECG at ED and the ECG were transmitted to the 3G mobile phone of an on-call interventional cardiologist within 10 minutes of ED arrival. Infarct team was activated and PPCI was performed by the interventional cardiologist. Fifty-four patients with acute STEMI underwent PPCI in the year prior to implementation of the tele-ECG served as subjects of the control group. The median D2BT of the tele-ECG group was 86 minutes, significantly shorter than the median time of 125 minutes of the control group (P &lt;0.0001). The proportion of patients who achieved a D2BT of &lt;90 minutes increased from 44% in the control group to 76% in the tele-ECG group (P=0.0001). Conclusions: The implementation of ED tele-ECG triage and interventional cardiologist activation of the infarct team can significantly improve D2BT and result in a greater proportion of patients achieving guideline recommendations.