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Автор: Grafiati

Опубліковано: 14 березня 2023

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1

Magnani, Jared W., Mary Ann Williamson, Patrick T. Ellinor, Kevin M. Monahan, and Emelia J. Benjamin. "P Wave Indices." Circulation: Arrhythmia and Electrophysiology 2, no. 1 (February 2009): 72–79. http://dx.doi.org/10.1161/circep.108.806828.

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2

Chhabra, Lovely. "Importance of P-wave indices in stroke." International Journal of Cardiology 203 (January 2016): 962–63. http://dx.doi.org/10.1016/j.ijcard.2015.11.102.

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3

He, Jinli, Gary Tse, Panagiotis Korantzopoulos, Konstantinos P. Letsas, Sadeq Ali-Hasan-Al-Saegh, Hooman Kamel, Guangping Li, Gregory Y. H. Lip, and Tong Liu. "P-Wave Indices and Risk of Ischemic Stroke." Stroke 48, no. 8 (August 2017): 2066–72. http://dx.doi.org/10.1161/strokeaha.117.017293.

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4

Christos, Goudis A. "P-wave indices in emphysema. What do we actually know?" International Journal of Cardiology 202 (January 2016): 80. http://dx.doi.org/10.1016/j.ijcard.2015.08.150.

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5

Mori, Nobuhito, Risako Kishimoto, and Tomoya Shimura. "WAVE CLIMATE VARIABILITY AND RELATED CLIMATE INDICES." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 75. http://dx.doi.org/10.9753/icce.v36.risk.75.

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Climate change is highly expected to give significant impact on coastal hazards and environment. The future projections of wave climate under global warming scenarios have been carried out and shows changes in wave heights depending on the regions (e.g., Hemer et al., 2013). Beside the long-term trends of wave climate, annual to decadal changes are also important to understand variability. For example, the North Atlantic Oscillation (NAO) is highly correlated to monthly mean wave height along the western European coast. However, variability of wave climate is not well understood over the globe, quantitatively. Additionally, the standard coastal engineers regard stationary process for wave environment for solving coastal problems. This study analyzes global wave climate variability for the last half century based on principal component analysis of atmospheric forcing (sea surface winds U10 and sea level pressure P) and wave hindcast.

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6

Nicoli, Charles D., Margaret Infeld, Sarah Wood, Zachary T. Smith, Sean Meagher, Shawn Wayne, Sherrie Khadanga, and Daniel Lustgarten. "CHANGES IN P-WAVE INDICES FOLLOWING RADIOFREQUENCY ABLATION FOR ATRIAL FIBRILLATION." Journal of the American College of Cardiology 77, no. 18 (May 2021): 260. http://dx.doi.org/10.1016/s0735-1097(21)01619-3.

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7

Gurukripa Kowlgi, N., and Lovely Chhabra. "The role of P-wave indices in the diagnosis of emphysema." International Journal of Cardiology 201 (December 2015): 148–49. http://dx.doi.org/10.1016/j.ijcard.2015.07.093.

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8

Dogan, Umuttan, Nasuh Utku Dogan, Ahmet Ozgur Basarir, Serkan Yildirim, Cetin Celik, Feyzanur Incesu, and Kurtulus Ozdemir. "P-wave parameters and cardiac repolarization indices: Does menopausal status matter?" Journal of Cardiology 60, no. 4 (October 2012): 333–37. http://dx.doi.org/10.1016/j.jjcc.2012.04.001.

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9

Snyder, Michelle L., Elsayed Z. Soliman, Eric A. Whitsel, Kapuaola S. Gellert, and Gerardo Heiss. "Short-term repeatability of electrocardiographic P wave indices and PR interval." Journal of Electrocardiology 47, no. 2 (March 2014): 257–63. http://dx.doi.org/10.1016/j.jelectrocard.2013.11.007.

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10

Tan, Isabella, Hosen Kiat, Edward Barin, Mark Butlin, and Alberto P. Avolio. "Effects of pacing modality on noninvasive assessment of heart rate dependency of indices of large artery function." Journal of Applied Physiology 121, no. 3 (September 1, 2016): 771–80. http://dx.doi.org/10.1152/japplphysiol.00445.2016.

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Studies investigating the relationship between heart rate (HR) and arterial stiffness or wave reflections have commonly induced HR changes through in situ cardiac pacing. Although pacing produces consistent HR changes, hemodynamics can be different with different pacing modalities. Whether the differences affect the HR relationship with arterial stiffness or wave reflections is unknown. In the present study, 48 subjects [mean age, 78 ± 10 (SD), 9 women] with in situ cardiac pacemakers were paced at 60, 70, 80, 90, and 100 beats per min under atrial, atrioventricular, or ventricular pacing. At each paced HR, brachial cuff-based pulse wave analysis was used to determine central hemodynamic parameters, including ejection duration (ED) and augmentation index (AIx). Wave separation analysis was used to determine wave reflection magnitude (RM) and reflection index (RI). Arterial stiffness was assessed by carotid-femoral pulse wave velocity (cfPWV). Pacing modality was found to have significant effects on the HR relationship with ED ( P = 0.01), central aortic pulse pressure ( P = 0.01), augmentation pressure ( P < 0.0001), and magnitudes of both forward and reflected waves ( P = 0.05 and P = 0.003, respectively), but not cfPWV ( P = 0.57) or AIx ( P = 0.38). However, at a fixed HR, significant differences in pulse pressure amplification ( P < 0.001), AIx ( P < 0.0001), RM ( P = 0.03), and RI ( P = 0.03) were observed with different pacing modalities. These results demonstrate that although the HR relationships with arterial stiffness and systolic loading as measured by cfPWV and AIx were unaffected by pacing modality, it should still be taken into account for studies in which mixed pacing modalities are present, in particular, for wave reflection studies.

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11

Magnani, Jared W., Victor M. Johnson, Lisa M. Sullivan, Steven A. Lubitz, Renate B. Schnabel, Patrick T. Ellinor, and Emelia J. Benjamin. "P-Wave Indices: Derivation of Reference Values from the Framingham Heart Study." Annals of Noninvasive Electrocardiology 15, no. 4 (October 2010): 344–52. http://dx.doi.org/10.1111/j.1542-474x.2010.00390.x.

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12

Pirinen, Jani, Jukka Putaala, and Mika Lehto. "Details on methods and further thoughts on P-wave indices in stroke." International Journal of Cardiology 216 (August 2016): 66–67. http://dx.doi.org/10.1016/j.ijcard.2016.04.034.

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13

Eranti, Antti, Jonas Carlson, Tuomas Kenttä, Fredrik Holmqvist, Arttu Holkeri, M. Anette Haukilahti, Tuomas Kerola, et al. "Orthogonal P-wave morphology, conventional P-wave indices, and the risk of atrial fibrillation in the general population using data from the Finnish Hospital Discharge Register." EP Europace 22, no. 8 (June 18, 2020): 1173–81. http://dx.doi.org/10.1093/europace/euaa118.

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Abstract Aims Identifying subjects at high and low risk of atrial fibrillation (AF) is of interest. This study aims to assess the risk of AF associated with electrocardiographic (ECG) markers linked to atrial fibrosis: P-wave prolongation, 3rd-degree interatrial block, P-terminal force in lead V1, and orthogonal P-wave morphology. Methods and results P-wave parameters were assessed in a representative Finnish population sample aged ≥30 years (n = 7217, 46.0% male, mean age 51.4 years). Subjects (n = 5489) with a readable ECG including the orthogonal leads, sinus rhythm, and a predefined orthogonal P-wave morphology type [positive in leads X and Y and either negative (Type 1) or ± biphasic (Type 2) in lead Z; Type 3 defined as positive in lead X and ± biphasic in lead Y], were followed 10 years from the baseline examinations (performed 1978–80). Subjects discharged with AF diagnosis after any-cause hospitalization (n = 124) were defined as having developed AF. Third-degree interatrial block was defined as P-wave ≥120 ms and the presence of ≥2 ± biphasic P waves in the inferior leads. Hazard ratios (HRs) and confidence intervals (CIs) were assessed with Cox models. Third-degree interatrial block (n = 103, HR 3.18, 95% CI 1.66–6.13; P = 0.001) and Type 3 morphology (n = 216, HR 3.01, 95% CI 1.66–5.45; P < 0.001) were independently associated with the risk of hospitalization with AF. Subjects with P-wave <110 ms and Type 1 morphology (n = 2074) were at low risk (HR 0.46, 95% CI 0.26–0.83; P = 0.006), compared to the rest of the subjects. Conclusion P-wave parameters associate with the risk of hospitalization with AF.

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14

Magnani, Jared W., Michael J. Mazzini, Lisa M. Sullivan, MaryAnn Williamson, Patrick T. Ellinor, and Emelia J. Benjamin. "P-Wave Indices, Distribution and Quality Control Assessment (from the Framingham Heart Study)." Annals of Noninvasive Electrocardiology 15, no. 1 (January 2010): 77–84. http://dx.doi.org/10.1111/j.1542-474x.2009.00343.x.

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15

Tachmatzidis, Dimitrios, Dimitrios Filos, Ioanna Chouvarda, Anastasios Tsarouchas, Dimitrios Mouselimis, Constantinos Bakogiannis, Charalampos Lazaridis, et al. "Beat-to-Beat P-Wave Analysis Outperforms Conventional P-Wave Indices in Identifying Patients with a History of Paroxysmal Atrial Fibrillation during Sinus Rhythm." Diagnostics 11, no. 9 (September 17, 2021): 1694. http://dx.doi.org/10.3390/diagnostics11091694.

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Early identification of patients at risk for paroxysmal atrial fibrillation (PAF) is essential to attain optimal treatment and a favorable prognosis. We compared the performance of a beat-to-beat (B2B) P-wave analysis with that of standard P-wave indices (SPWIs) in identifying patients prone to PAF. To this end, 12-lead ECG and 10 min vectorcardiogram (VCG) recordings were obtained from 33 consecutive, antiarrhythmic therapy naïve patients, with a short history of low burden PAF, and from 56 age- and sex-matched individuals with no AF history. For both groups, SPWIs were calculated, while the VCG recordings were analyzed on a B2B basis, and the P-waves were classified to a primary or secondary morphology. Wavelet transform was used to further analyze P-wave signals of main morphology. Univariate analysis revealed that none of the SPWIs performed acceptably in PAF detection, while five B2B features reached an AUC above 0.7. Moreover, multivariate logistic regression analysis was used to develop two classifiers—one based on B2B analysis derived features and one using only SPWIs. The B2B classifier was found to be superior to SPWIs classifier; B2B AUC: 0.849 (0.754–0.917) vs. SPWIs AUC: 0.721 (0.613–0.813), p value: 0.041. Therefore, in the studied population, the proposed B2B P-wave analysis outperforms SPWIs in detecting patients with PAF while in sinus rhythm. This can be used in further clinical trials regarding the prognosis of such patients.

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16

Alexander, Bryce, Gary Tse, Manuel Martinez-Selles, and Adrian Baranchuk. "Atrial Conduction Disorders." Current Cardiology Reviews 17, no. 1 (March 11, 2021): 68–73. http://dx.doi.org/10.2174/1573403x17666210112161524.

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Atrial conduction disorders result from impaired propagation of cardiac impulses from the sinoatrial node through the atrial conduction pathways. Disorders affecting interatrial conduction alter P-wave characteristics on the surface electrocardiogram. A variety of P-wave indices reflecting derangements in atrial conduction have been described and have been associated with an increased risk of atrial fibrillation (AF) and stroke. Interatrial block (IAB) is the most well-known of the different P-wave indices and is important clinically due to its ability to predict patients who are at risk of the development of AF and other supraventricular tachycardias. P-Wave Axis is a measure of the net direction of atrial depolarization and is determined by calculating the net vector of the P-wave electrical activation in the six limb-leads using the hexaxial reference system. It has been associated with stroke and it has been proposed that this variable be added to the existing CHA2DS2-VASc score to create a P2-CHA2DS2-VASc score to improve stroke prediction. P-Terminal Force in V1 is thought to be an epiphenomenon of advanced atrial fibrotic disease and has been shown to be associated with a higher risk of death, cardiac death, and congestive heart failure as well as an increased risk of AF. P-wave Dispersion is defined as the difference between the shortest and longest P-wave duration recorded on multiple concurrent surface ECG leads on a standard 12-lead ECG and has also been associated with the development of AF and AF recurrence. Pwave voltage in lead I (PVL1) is thought to be an electrocardiographic representation of cardiac conductive properties and, therefore, the extent of atrial fibrosis relative to myocardial mass. Reduced PVL1 has been demonstrated to be associated with new-onset AF in patients with coronary artery disease and may be useful for predicting AF. Recently a risk score (the MVP risk score) has been developed using IAB and PVL1 to predict atrial fibrillation and has shown a good predictive ability to determine patients at high risk of developing atrial fibrillation. The MVP risk score is currently undergoing validation in other populations. This section reviews the different P-wave indices in-depth, reflecting atrial conduction abnormalities.

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17

Leung, Maurice P., Peter T. S. Lo, Roxy N. S. Lo, Henry Cheung, and Che-Keung Mok. "The changes in right ventricular diastolic indices in babies with pulmonary atresia and intact ventricular septum undergoing corrective surgery: a pulsed Doppler echocardiographic study." Cardiology in the Young 1, no. 2 (April 1991): 114–22. http://dx.doi.org/10.1017/s1047951100000226.

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SummaryWe used pulsed Doppler echocardiography to study the right ventricular diastolic function of29 normal babies and 12 neonates with pulmonary atresia and intact ventricular septum. Eleven patients underwent staged operations of closed pulmonaryvalvotomy followed by either rightventricular outflow reconstruction (n=5) or balloon angioplasty of the pulmonary valve (n=3). In normal babies, the Doppler wave form showed dominant early (E) and separate late active (A) waves of activity, when the heart rate was slow (<100/min). The two waves gradually merged with increasing heart rate, to form a monophasic active wave. Prior to any intervention, all except one of our patients had only a monophasic active right ventricular filling wave over the entire range of heart rates recorded. To quantitate these differences in ventricular filling, we derived 4 diastolic indices from the ratio of: the peak velocity of the early versus the late active wave (EIA); the integral with time of these waves (E/Aarea); the time of diastolic filling relative to the cardiac cycle (TIRR); and the peak diastolic filling velocity relative to the mean filling velocity over the cardiac cycle (Velocity Index). Profiles of the indices against heart rate for both normal controls and patients indicated that only the index of the time of diastolic filling (T/RR) and the Velocity Index were appropriate for our serial comparisons. Thus, for neonates with pulmonary atresia, the index of the time (TIRR) was significantly lower (0.29±0.03 vs 0.43±0.04, p<0.01) and the Velocity Index higher (5.98±0.79 vs 3.98 ±0.31, p<0.001) than those of normal. After valvotomy, but with a poor surgical result, babies continued to have a predominantly monophasic right ventricular filling pattern without significant improvement (p>0.05) of the index of time (T/RR=0.29±0.05) or velocity (5.88±1.17). Babies who underwent a second stage procedure and achieved a final good result had predominantly biphasic right ventricular diastolic filling waves with significant progression (p<0.001) in the index of time (T/RR=0.42±0.03) and velocity (4.09±0.49).

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18

Magnani, Jared W., Faye L. Lopez, Elsayed Z. Soliman, Richard F. Maclehose, Richard S. Crow, and Alvaro Alonso. "P Wave Indices, Obesity, and the Metabolic Syndrome: The Atherosclerosis Risk in Communities Study." Obesity 20, no. 3 (March 2012): 666–72. http://dx.doi.org/10.1038/oby.2011.53.

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19

Gorodeski, Eiran Z., Jared W. Magnani, Ronald J. Prineas, Mara Z. Vitolins, Mary J. O’Sullivan, Elsayed Z. Soliman, Lisa W. Martin, et al. "EPIDEMIOLOGY OF P WAVE INDICES IN HEALTHY POST-MENOPAUSAL WOMEN: THE WOMEN’S HEALTH INITIATIVE." Journal of the American College of Cardiology 55, no. 10 (March 2010): A13.E125. http://dx.doi.org/10.1016/s0735-1097(10)60126-x.

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20

Al-Auqbi, Tawfeeq F. R., Mawada Mousa Funjan, and Isam N. S. Al-Karawi. "Importance of P-Wave Indices in a Sample of Iraqi Type 2 Diabetic Patients." Journal of Al-Nahrain University Science 15, no. 3 (September 1, 2012): 13–128. http://dx.doi.org/10.22401/jnus.15.3.17.

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21

O’Neill, James, Katrina Bounford, Alice Anstey, Jesvita D’Silva, Lisa Clark, Sven Plein, and Muzahir H. Tayebjee. "P wave indices, heart rate variability and anthropometry in a healthy South Asian population." PLOS ONE 14, no. 8 (August 23, 2019): e0220662. http://dx.doi.org/10.1371/journal.pone.0220662.

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22

Chamaidi, Aikaterini, Georgios Karagiannis, Aikaterini Christidi, Charalambos Parisis, Konstantinos Koutrakis, Andrew Xanthopoulos, John Skoularigis, Gregory Giamouzis та Filippos K. Triposkiadis. "Favorable Pulse Wave Augmentation Indices and Left Ventricular Diastolic Profile in β-Thalassemia Minor". Angiology 68, № 10 (3 квітня 2017): 899–906. http://dx.doi.org/10.1177/0003319717701658.

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β-Thalassemia minor (β-Τm) is associated with rheological and biochemical alterations that can affect cardiovascular function. We aimed to evaluate the elastic arterial properties and the pulse wave augmentation indices in a population of patients with β-Τm. Seventy-five individuals with β-Τm (age 55.5 [42.75-65.25], women 48%) and 127 controls (age 57 years [48-63], women 55.1%) underwent comprehensive echocardiographic evaluation and applanation tonometry of the radial and femoral artery. Pulse wave analysis revealed that augmentation pressure, augmentation index (AIx), and heart rate–corrected AIx were significantly lower (median [interquartile range]: 8.75 [4.625-13] vs 11 [6.5-14.5], P = .017; 26.5 [17.5-33.375] vs 30.5 [20.75-37.5], P = .014; and 22.25 [15.125-29.5] vs 27 [20.5-33], P = .008, respectively) in the β-Τm group compared to controls. The left atrial active emptying volume was significantly lower and the isovolumic relaxation time was shorter in the β-Τm group compared to the control group (10.2 [7.4-14.4] vs 12.0 [8.6-15.8], P = .040 and 78 [70-90] vs 90 [70-104], P = .034, respectively). β-Thalassemia minor is associated with favorable pulse wave augmentation indices and left ventricular diastolic function profile in asymptomatic individuals with cardiovascular risk factors.

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23

Ortigosa, Nuria, Guillermo Ayala, and Óscar Cano. "Variation of P-wave indices in paroxysmal atrial fibrillation patients before and after catheter ablation." Biomedical Signal Processing and Control 66 (April 2021): 102500. http://dx.doi.org/10.1016/j.bspc.2021.102500.

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24

KORKUSHKO, O. "P.1.5 Indices of P-wave signal averaged ECG and left ventricle function condition in patients with atrial fibrillation." Europace 4 (October 2003): A34—A35. http://dx.doi.org/10.1016/s1099-5129(02)90154-6.

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25

Korkushko, O. V., O. S. Sychov, M. A. Zayats, V. Yu Lishnevskaya, and D. T. Malidze. "P.1.5 Indices of P-wave signal averaged ECG and left ventricle function condition in patients with atrial fibrillation." EP Europace 4, Supplement_1 (October 1, 2003): A34—A35. http://dx.doi.org/10.1016/eupace/4.supplement_1.a34-d.

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26

Artaç, İnanç, Bahattin Balcı, Serdar Sevimli, Ahmet Karakurt, İbrahim Rencüzoğulları, Metin Çağdaş, Yavuz Karabağ, and Doğan İliş. "The Relationship Between Electrocardiographic P Wave Parameters and Left Atrial Volume and Volume Indices in Patients with Hypertension." Koşuyolu Heart Journal 25, no. 2 (August 1, 2022): 177–86. http://dx.doi.org/10.51645/khj.2022.m213.

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Introduction: This study was designed to evaluate the relationship between left atrial volume index, which is an important indicator of left ventricular diastolic dysfunction, and electrocardiographic parameters such as P wave duration, P wave dispersion (PWDISP), P wave terminal force (PWTF), and P wave peak time (PWPT) in hypertensive patients. Patients and Methods: A total of 58 patients with a diagnosis of hypertension between June 2017 and April 2018 were included in this retrospective study. Age-sex matched 58 healthy subjects constituted the control group. The patients without diastolic dysfunction and stage I diastolic dysfunction were included in the normal left atrial pressure (NLAP) group, while stage II and stage III diastolic dysfunction patients constituted the high left atrial pressure (HLAP) group. Results: The PWDmax, PWDISP, and PWPT which are calculated from the lead DII (PWPTDII) were found to be longer in the group of hypertensive patients (p< 0.05, for all). Electrocardiographic parameters of PWDmax, PWDISP, PWTF, PWPTDII, and PWPTVI were found to be longer in patients with HLAP. Both PWPTVI (p= 0.008 r= 0.395) and PWPTDII (p< 0.001 r= 0.456) were significantly correlated with left atrial volume index. Conclusion: In this study, the relationship between PWPT and diastolic dysfunction was revealed for the first time in the literature. In addition, the PWPT was found to be increased in patients with increased left atrial pressure (LAP). Our findings deserve attention because electrocardiography is an inexpensive and easily accessible diagnostic method that can be used to detect diastolic dysfunction in hypertensive patients.

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27

He, Ye, Kui Wang, Yuehui Ji, Guoyin Wu, and Mingjie Zhao. "Evaluation of Cumulative Damage of Sandstone under Cyclic Wetting and Drying through Acoustic Wave Parameters and Resistivity Testing." Journal of New Materials for Electrochemical Systems 23, no. 4 (December 31, 2020): 256–61. http://dx.doi.org/10.14447/jnmes.v23i4.a06.

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This paper carries out cyclic wetting and drying experiments on the sandstones from the bank slope of an inland port, and explores the deterioration features and acoustic wave parameters and resistivity (AWPR) of the sandstone. The variations in P-wave velocity, attenuation coefficient, nonlinear coefficient, resistivity, and other indices with the cycle number were discussed in details. Then, the correlations between P-wave velocity, resistivity, and physical-mechanical indices were analyzed based on the experimental results. Through the analysis on instantaneous damage analysis, a cumulative damage model was proposed, in the light of the AWPR. The results show that: the evolution of sandstone resistivity can accurately reflect the deterioration features of the sandstone under cyclic wetting and drying, providing a desirable tool to characterize rock strength deterioration and internal damage changes. Taking cycle number into account, the proposed theoretical model for cumulative damage can derive the damage and deterioration of sandstone excellently. By this model, the AWPR at any moment can be acquired in real time on site, which is convenient for engineering application.

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28

Hu, Xiaoliang, Jingzhou Jiang, Yuedong Ma, and Anli Tang. "Novel P Wave Indices to Predict Atrial Fibrillation Recurrence After Radiofrequency Ablation for Paroxysmal Atrial Fibrillation." Medical Science Monitor 22 (July 24, 2016): 2616–23. http://dx.doi.org/10.12659/msm.896675.

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29

Kahyaoglu, Osman K., Mustafa Yildiz, Pinar Pazarli, Olcay Semiz, İsmail Sakar, Mehmet Mihmanli, and Birsel Kavakli. "A comparison of P-wave dispersion in trained healthy young students with various body mass indices." Journal of Electrocardiology 40, no. 4 (July 2007): S57. http://dx.doi.org/10.1016/j.jelectrocard.2007.03.386.

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30

Aizawa, Yoshifusa, Takao Sato, and Kohei Akazawa. "Prevalence, significance and reversal of abnormal P-wave indices in hypertension: A review and meta-analysis." Journal of Electrocardiology 53 (March 2019): 13–17. http://dx.doi.org/10.1016/j.jelectrocard.2018.12.008.

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31

Groner, Abraham, Jen Yau, Irene D. Lytrivi, H. Helen Ko, James C. Nielsen, Ira A. Parness, and Shubhika Srivastava. "The role of right ventricular function in paediatric idiopathic dilated cardiomyopathy." Cardiology in the Young 23, no. 3 (August 23, 2012): 409–15. http://dx.doi.org/10.1017/s104795111200114x.

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AbstractIntroductionThe prevalence of right ventricular dysfunction in idiopathic dilated cardiomyopathy is incompletely studied in children. Furthermore, right ventricular function may signal worse outcomes. We evaluated recently published right ventricular function echocardiographic indices in identifying dysfunction in children with idiopathic dilated cardiomyopathy and the impact of right ventricular dysfunction on long-term prognosis.MethodsA retrospective database review of right ventricular function indices in 30 patients with idiopathic dilated cardiomyopathy was compared with 60 age- and sex-matched controls from January, 2001 until December, 2010. Right ventricular function was assessed by Doppler tissue peak systolic S′, early and late diastolic E′ and A′ waves and isovolumic acceleration at the tricuspid valve annulus; pulsed wave Doppler tricuspid valve inflow E and A waves; right ventricular myocardial performance index; tricuspid annular plane systolic excursion; right ventricular fractional area change.ResultsRight ventricular systolic and diastolic function in idiopathic dilated cardiomyopathy was significantly impaired. All measured indices except for isovolumic acceleration and fractional area change were significantly reduced, with a p-value less than 0.05. There was no right ventricular index predictive of death or transplantation. Patients with poor outcome were significantly more likely to need inotropic support (p-value equal to 0.018), be placed on a ventricular assist device (p equal to 0.005), and have a worse left ventricular ejection fraction z-score (p-value equal to 0.002).ConclusionRight ventricular dysfunction is under-recognised in children presenting with idiopathic dilated cardiomyopathy. The need for clinical circulatory support and left ventricular ejection fraction z-score less than minus 8 were primary determinants of outcome, independent of the degree of derangement in right ventricular function.

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Graettinger, William F., Deanna G. Cheung, and Michael A. Weher. "P-Wave Configuration as an Indicator of Echocardiographic Indices of Cardiac Structure and Function in Normotensive Adolescents." Chest 97, no. 4 (April 1990): 896–900. http://dx.doi.org/10.1378/chest.97.4.896.

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C. Yao, Regina, Jansen R. Mancera, and Marcellus Francis Ramirez. "Non-Hypertensive Patients with Prolonged P-Wave Indices Have Higher Blood Pressure Response to Exercise Stress Test." Journal of Arrhythmia 27, Supplement (2011): PE3_002. http://dx.doi.org/10.4020/jhrs.27.pe3_002.

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Gulsen, Kamil, Orhan Ince, Taylan Akgun, Serdar Demir, Abdulkadir Uslu, Ayhan Kup, Lutfi Ocal, et al. "The effect of P wave indices on new onset atrial fibrillation after trans-catheter aortic valve replacement." Journal of Electrocardiology 61 (July 2020): 71–76. http://dx.doi.org/10.1016/j.jelectrocard.2020.06.001.

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Parikh, Nisha I., Kristopher Kapphahn, Haley Hedlin, Jeffrey E. Olgin, Matthew A. Allison, Jared W. Magnani, Kelli R. Ryckman, Molly E. Waring, Marco Valentin Perez, and Barbara V. Howard. "Effects of reproductive period duration and number of pregnancies on midlife ECG indices: a secondary analysis from the Women’s Health Initiative Clinical Trial." BMJ Open 8, no. 8 (August 2018): e019129. http://dx.doi.org/10.1136/bmjopen-2017-019129.

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ObjectivesPregnancy, menses and menopause are related to fluctuations in endogenous sex hormones in women, which cumulatively may alter cardiac electrical conduction. Therefore, we sought to study the association between number of pregnancies and reproductive period duration (RD, time from menarche to menopause) with ECG intervals in the Women’s Health Initiative Clinical Trials.DesignSecondary analysis of multicentre clinical trial.SettingUSA.Primary outcome measuresECGintervals: PR interval, P-wave duration, P-wave dispersion, QTc interval.Participantsn=40 687 women (mean age=62 years) participating in the Women’s Health Initiative Clinical Trials. 82.5% were white, 9.3% black, 4% Hispanic and 2.7% Asian.MethodsIn primary analysis, we employed multivariable linear regression models relating number of pregnancies and RD with millisecond changes in intervals from enrolment ECG. We studied effect modification by hormone therapy use.ResultsAmong participants, 5+ live births versus 0 prior pregnancies was associated with a 1.32 ms increase in PR interval (95% CI 0.25 to 2.38), with a graded association with longer QTc interval (ms) (none (prior pregnancy, no live births)=0.66 (–0.56 to 1.88), 1=0.15 (–0.71 to 1.02), 2–4=0.25 (–0.43 to 0.94) and 5+ live births=1.15 (0.33 to 1.98), p=0.008). RD was associated with longer PR interval and maximum P-wave duration (but not P-wave dispersion) among never users of hormone therapy: (PR (ms) per additional RD year: 0.10 (0.04 to 0.16); higher P-wave duration (ms): 0.09 (0.06 to 0.12)). For every year increase in reproductive period, QTc decreased by 0.04 ms (−0.07 to –0.01).ConclusionsAn increasing number of live births is related to increased and RD to decreased ventricular repolarisation time. Both grand multiparity and longer RD are related to increased atrial conduction time. Reproductive factors that alter midlife cardiac electrical conduction system remodelling in women may modestly influence cardiovascular disease risk in later life.Trial registration numberNCT00000611; Post-results.

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Ma, Fang, Jimei Xu, Weiwei Yang, and Fuqin Bian. "Clinical Study of Ultrasonic Extreme Velocity Imaging Pulse Wave Technique in Carotid Elasticity in Patients with Type II Diabetes Mellitus." Journal of Biomaterials and Tissue Engineering 11, no. 6 (June 1, 2021): 1138–43. http://dx.doi.org/10.1166/jbt.2021.2668.

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In this study, extreme velocity ultrasonic imaging pulse wave technology was used to detect the main indices of atherosclerosis such as carotid intima-media thickness (IMT) and carotid elasticity, and biochemical indices such as glycated hemoglobin, blood glucose and blood lipids in one hundred twenty 18–60-year-old patients with type II diabetes mellitus (T2DM) and 120 healthy controls. We analyzed the correlations between carotid elasticity, carotid IMT, and a range of biochemical indices. The results indicated that when the carotid IMT in young and middle-aged patients with T2DM was within the normal range (0.56±0.03 mm), the carotid artery elasticity was abnormal [Pulse wave propagation velocity (PWV)-BS = 7.69± 1.26 m/s; PWV-ES = 8.34±1.51 m/s; P < 0.05]. Additionally, PWV-BS was positively correlated with age, course of the disease, glycated hemoglobin (HbA1c), and fasting blood glucose (FBG) (r = 0.297, 0.377, 0.369, 0.382), and PWV-ES was positively correlated with age, course of the disease, HbA1c, and FBG (r = 0.318, 0.386, 0.392, 0.339). This finding provides a basis for extreme velocity ultrasonic imaging pulse wave technology to become a new method for the early screening of atherosclerosis in patients with T2DM; this is important for timely clinical intervention in patients with T2DM.

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Dirandeh, E., H. Kohram, and M. Aryanezhad. "517. RELATIONSHIPS OF LUTEAL PHASE VARIABLES (PRIOR TO AI) WITH FOLLICULAR WAVES IN DAIRY COWS." Reproduction, Fertility and Development 21, no. 9 (2009): 116. http://dx.doi.org/10.1071/srb09abs517.

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This study was done to consider relationships of luteal phase variables (prior to AI) with follicular waves. The estrous cycles of 10 cows were synchronized with 2 im injections of prostaglandin F2α given 11 d apart. The cows were randomly assigned to 1 of 2 treatments. Cows in the control treatment received no treatment, whereas GnRH6 cows received a GnRH injection on d 6 of the estrous cycle (estrus = d 0). Daily, from estrus d 0 to the next estrus d 23, cows had their ovaries scanned by ultrasound. Blood samples were collected by tail following each ultrasound examination from estrus until next estrus (estrus = d 0). Concentrations of plasma progesterone were determined by radioimmunoassay kit. The limit of detection of the assay was 0.125 ng/mL and the intra- and interassay coefficients of variation were 8.4% and 10.2%, respectively. Data that were analyzed by using PROC GLM of SAS. For comparisons between groups, the 2-sample t-test was used for continuous traits, such as size of cl or hormone concentrations. Prospective comparisons of indices of progesterone indicated that the length of luteal lifespan was longer in three-wave than in two-wave cows (P<0.01). Plasma progesterone concentrations were similar at peak and measured as area under the curve on day 5 through 17 preceding insemination in two-wave (6.70±0.30 ng/ml) and three-wave cows (7.30±0.50 ng/ml). Length of the luteal phase (defined as from the day of estrus until the last day on which plasma progesterone remained greater than 2 ng/ml) was <2 days shorter in two-wave cows than in three-wave cows (16.7±0.30 vs. 18.40±0.50 d; P<0.05). In addition, the day of peak progesterone occurred earlier in two-wave cows (13.50±0.40 vs. 16.30±0.70 d; P<0.05).

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Dattilo, Giuseppe, Egidio Imbalzano, Matteo Casale, Claudio Guarneri, Francesco Borgia, Stefania Mondello, Pasqualina Laganà, Pietro Romano, Giuseppe Oreto, and Sarafinella Cannavò. "Psoriasis and Cardiovascular Risk: Correlation Between Psoriasis and Cardiovascular Functional Indices." Angiology 69, no. 1 (March 21, 2017): 31–37. http://dx.doi.org/10.1177/0003319717699329.

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Evidence suggests that psoriasis together with other cardiovascular (CV) risk factors is associated with increased vascular morbidity, but it is not clear whether psoriasis is an independent risk factor. Consecutive patients (n = 33; 35.6 ± 5.7 years; 13 females) with mild psoriasis (Psoriasis Area and Severity Index <10) without comorbidities and 33 healthy participants (36.3 ± 5.9 years; 15 females) were enrolled. Both groups underwent echocardiography, speckle tracking (2-dimensional strain echocardiography [2D-SE]), and pulse wave velocity (PWV) testing. Clinical and conventional echocardiographic characteristics were comparable between both groups. Global longitudinal strain (GLS) was significantly lower ( P = .002) in the psoriasis group (22.39% ± 2.28%) than in controls (24.15% ± 2.17%). The PWV was significantly lower ( P = .004) in controls (8.06 ± 1.68 m/s) than in the psoriasis group (9.23 ± 1.53 m/s). Significant correlations between GLS and disease duration ( r = −.66, P < .0001) and between GLS and patient age at diagnosis ( r = .48, P = .0043) were found. Psoriasis may be an independent CV risk factor, causing cardiac and vascular impairment. Both 2D-SE and PWV may be useful tools for the screening of CV risk in these patients.

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Garadah, Taysir S., Salah Kassab, Najat Mahdi, Ahmed Abu-Taleb, and Anwer Jamsheer. "Pulsed and Tissue Doppler Echocardiographic Changes in Patients with Thalassemia Major." Clinical medicine. Blood disorders 3 (January 2010): CMBD.S4377. http://dx.doi.org/10.4137/cmbd.s4377.

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Background Doppler echocardiographic studies of left ventricle (LV) systolic and diastolic function in patients with β-Thalassemia Major (β-TM) had shown different patterns of systolic and diastolic dysfunction. Aim This cross-sectional study was designed to study the LV systolic and diastolic function in patients with β-TM using Pulsed Doppler (PD) and Tissue Doppler (TD) echocardiography. Methods All patients were evaluated clinically and by echocardiography, The study included patients with β-TM (n = 38, age 15.7 ± 8.9 years) compared with an age-matched control group (n = 38, age 15.9 ± 8.9 years). The pulse Doppler indices were normalized for age and heart rate. Results Compared with control patients, M-Mode showed that patients with β-TM have thicker LV septal wall index (0.659 ± 0.23 vs. 0.446 ± 0.219 cm, P ≤ 0.001), posterior wall index (0.659 ± 0.235 vs. 0.437 ± 0.214 cm, P ≤ 0.01), and larger LVEDD index is (3.99 ± 0.48 vs. 2.170 ± 0.57 mm. P = 0.035). Pulsed Doppler showed high LV trans-mitral E wave velocity (70.818 ± 10.139 vs. 57.532 ± 10.139, p = 0.027) and E/A ratio (1.54 vs. 1.23, P ≤ 0.01). The duration of Deceleration time (DT) and isovolumic relaxation time (IVRT) were significantly shorter in patients with β-TM (150.234 ± 20.0.23 vs. 167.123 ± 19.143 msec, P ≤ 0.01) and (60.647 ± 6.77 vs. 75.474 ± 5.83 msec, P ≤ 0.001), respectively. The ratio of transmitral E wave velocity to the tissue Doppler E wave at the basal septal mitral annulus E/Em– was significantly higher in β-TM group (14.024 ± 2.29 vs. 12.132 ± 1.82, P ≤ 0.01). The Tissue Doppler systolic velocity (Sm) and the early diastolic velocity (Em) were significantly lower in β-TM group compared to control (4.31 ± 1.2 cm/s vs. 6.95 ± 2.1, P ≤ 0.01 and 4.31 ± 2.7 cm/s vs. 5.82 ± 2.5, P ≤ 0.01) respectively. The tricuspid valve velocity was significantly higher than controls (2.993 ± 0.569 vs. 1.93 ± 0.471 m/sec, respectively, P ≤ 0.01). However, the LVEF% and fractional shortening were normal with no significant difference in both groups. Conclusion In this study, patients with β-thalassemia major compared with controls, have significantly thicker LV wall, and larger LV cavity and LV diastolic filling indices suggestive of restrictive pattern with a higher tricuspid valve velocity. These data showed that left ventricle diastolic indices are compromised initially in patients with β-thalassemia major.

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Satsukawa, T., B. Ildefonse, D. Mainprice, L. F. G. Morales, K. Michibayashi, and F. Barou. "A database of plagioclase crystal preferred orientations (CPO) and microstructures – implications for CPO origin, strength, symmetry and seismic anisotropy." Solid Earth Discussions 5, no. 2 (August 14, 2013): 1191–257. http://dx.doi.org/10.5194/sed-5-1191-2013.

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Abstract. This study presents a unique database of 170 plagioclase Crystallographic Preferred Orientations (CPO) of variously deformed gabbroic rocks. The CPO characteristics as a function of the deformation regime (magmatic or crystal-plastic) are outlined and discussed. The studied samples are dominantly from slow- and fast-spread present-day ocean crust, as well as from the Oman ophiolite. Plagioclase is the dominant mineral phase in the studied samples. Plagioclase CPOs are grouped in three main categories: Axial-B, a strong point alignment of (010) with a girdle distribution of [100]; Axial-A, a strong point maximum concentration of [100] with parallel girdle distributions of (010) and (001); and P-type, point maxima of [100], (010), and (001). A majority of CPO patterns are Axial-B and P-type, in samples showing either magmatic or crystal-plastic deformation textures. Axial-A CPOs are less common; they represent 21% of the samples deformed by crystal-plastic flow. Although fabric strength (ODF J-index) does not show any consistent variation as a function of the CPO patterns, there is a significant difference in the relationship between the ODF and pole figures J-indices; the magmatic type microstructures have high (010) pole figures J-indices, which increase linearly with ODF J-index, whereas the high [100] pole figures J-indices of plastically deformed samples vary in a more scattered manner with ODF J-index. The multistage nature of plastic deformation superposed on a magmatic structure compared with magmatic flow, and the large number of possible slip-systems in plagioclase probably account for these differences. Calculated seismic properties (P wave and S wave velocities and anisotropies) of plagioclase aggregates show that anisotropy (up to 12% for P wave and 14% for S wave) tends to increase as a function of ODF J-index. In comparison with the olivine 1998 CPO database, the magnitude of P wave anisotropy for a given J-index is much less than olivine, whereas it is similar for S wave anisotropy. Despite a large variation of fabric patterns and geodynamic setting, seismic properties of plagioclase-rich rocks have similar magnitudes of anisotropy. There is a small difference in the aggregate elastic symmetry, with magmatic microstructures having higher orthorhombic and hexagonal components, whereas plastic deformation microstructures have a slightly higher monoclinic component, possibly correlated with predominant monoclinic simple shear flow in plastically-deformed samples. Overall, plots for CPO strength (ODF J-index), pole figure strength, CPO symmetry and seismic anisotropy show significant scattering. This could be related to sampling statistics, although our database is a factor of ten higher than the olivine database of 1998, or it could be related to the low symmetry (triclinic) structure of plagioclase resulting in the addition of degrees of freedom in the processes creating the CPOs.

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41

Satsukawa, T., B. Ildefonse, D. Mainprice, L. F. G. Morales, K. Michibayashi, and F. Barou. "A database of plagioclase crystal preferred orientations (CPO) and microstructures – implications for CPO origin, strength, symmetry and seismic anisotropy in gabbroic rocks." Solid Earth 4, no. 2 (December 18, 2013): 511–42. http://dx.doi.org/10.5194/se-4-511-2013.

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Abstract. This study presents a unique database of 172 plagioclase Crystallographic Preferred Orientations (CPO) of variously deformed gabbroic rocks. The CPO characteristics as a function of the deformation regime (magmatic or crystal-plastic) are outlined and discussed. The studied samples are dominantly from slow- and fast-spread present-day ocean crust, as well as from the Oman ophiolite. Plagioclase is the dominant mineral phase in the studied samples. Plagioclase CPOs are grouped into three main categories: Axial-B, a strong point alignment of (010) with a girdle distribution of [100]; Axial-A, a strong point maximum concentration of [100] with parallel girdle distributions of (010) and (001); and P-type, point maxima of [100], (010), and (001). A majority of CPO patterns are Axial-B and P-type, in samples showing either magmatic or crystal-plastic deformation textures. Axial-A CPOs are less common; they represent 21% of the samples deformed by crystal-plastic flow. Although fabric strength (ODF J index) does not show any consistent variation as a function of the CPO patterns, there is a significant difference in the relationship between the ODF and pole figures J indices; the magmatic type microstructures have high (010) pole figures J indices, which increase linearly with ODF J index, whereas the high [100] pole figures J indices of plastically deformed samples vary in a more scattered manner with ODF J index. The multistage nature of plastic deformation superposed on a magmatic structure compared with magmatic flow, and the large number of possible slip-systems in plagioclase probably account for these differences. Calculated seismic properties (P wave and S wave velocities and anisotropies) of plagioclase aggregates show that anisotropy (up to 12% for P wave and 14% for S wave) tends to increase as a function of ODF J index. In comparison with the olivine 1998 CPO database, the magnitude of P wave anisotropy for a given J index is much less than olivine, whereas it is similar for S wave anisotropy. Despite a large variation of fabric patterns and geodynamic setting, seismic properties of plagioclase-rich rocks have similar magnitudes of anisotropy. There is a small difference in the aggregate elastic symmetry, with magmatic microstructures having higher orthorhombic and hexagonal components, whereas plastic deformation microstructures have a slightly higher monoclinic component, possibly correlated with predominant monoclinic simple shear flow in plastically deformed samples. Overall, plots for CPO strength (ODF J index), pole figure strength, CPO symmetry and seismic anisotropy show significant scattering. This could be related to sampling statistics, although our database is a factor of ten higher than the olivine database of 1998, or it could be related to the low symmetry (triclinic) structure of plagioclase resulting in the addition of degrees of freedom in the processes creating the CPOs.

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Yamamoto, Shigetada, Hideko Ono, Hiroshi Motoyama, Hiroshi Tachikawa, Minoru Tagawa, Kohei Akazawa, and Yoshifusa Aizawa. "P-wave indices in Japanese patients with ischemic stroke: Implication of atrial myopathy in subtype of ischemic stroke." Journal of Electrocardiology 66 (May 2021): 18–22. http://dx.doi.org/10.1016/j.jelectrocard.2021.02.010.

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Mugnai, Giacomo, Gian-Battista Chierchia, Carlo de Asmundis, Justo Juliá, Giulio Conte, Juan Sieira-Moret, Lucio Capulzini, et al. "P-wave indices as predictors of atrial fibrillation recurrence after pulmonary vein isolation in normal left atrial size." Journal of Cardiovascular Medicine 17, no. 3 (March 2016): 194–200. http://dx.doi.org/10.2459/jcm.0000000000000220.

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Pizoń, Tomasz, Marek Rajzer, Wiktoria Wojciechowska, Tomasz Drożdż, Dorota Drożdż, Marta Rojek, Krystian Gruszka, and Danuta Czarnecka. "Plasma renin activity, serum aldosterone concentration and selected organ damage indices in essential arterial hypertension." Archives of Medical Science 17, no. 1 (January 5, 2021): 9–18. http://dx.doi.org/10.5114/aoms.2018.73333.

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IntroductionThe aim of this study was to assess the relations between plasma renin activity (PRA), serum aldosterone concentration (ALDO) and selected asymptomatic organ damage (AOD) indices in mild primary arterial hypertension (AH).Material and MethodsWe measured PRA, ALDO, and selected AOD indices (carotid-femoral pulse wave velocity (cfPWV), central aortic pulse pressure (cPP), estimated glomerular filtration rate (eGFR)) in 122 patients with untreated AH.ResultsPatients with high PRA (≥ 0.65 ng/ml/h) were characterized by lower plasma sodium and aldosterone to renin ratio (ARR), higher ALDO, but a similar level of AOD indices compared to patients with low PRA. cfPWV (p = 0.04) and cPP (p = 0.019) increased with ARR, while eGFR decreased with ALDO (p = 0.008). Only eGFR was independently correlated with ALDO. In subjects with simultaneously high PRA and ARR values, we found significantly higher cfPWV (p = 0.02) and cPP (p = 0.04) and lower eGFR (p = 0.02) than in those with high PRA but low ARR values.ConclusionsAssessment of the influence of the renin-angiotensin-aldosterone system (RAAS) on AOD should include the relationship between renin and aldosterone. The PRA itself has no predictive value for AOD. More advanced arterial stiffness and renal impairment are associated with increased PRA and ARR. The RAAS activity might be useful in AOD prediction and hypertension severity assessment.

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Al-Shawwa, B., J. Cruz, Z. Ehsan, and D. G. Ingram. "0889 Utility of Pulse Wave Amplitude in Detecting Arousals in Children." Sleep 43, Supplement_1 (April 2020): A338—A339. http://dx.doi.org/10.1093/sleep/zsaa056.885.

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Abstract Introduction Identifying and scoring arousals are crucial to score hypopneas and respiratory efforts related arousals (RERAs). At the same time, children’s sleep architecture appears to be more stable compared to adults which makes it more difficult to score arousals. Pulse wave amplitude (PWA) is a signal obtained from finger photoplethysmography which is directly and positively correlated to finger blood flow. It is also used as a marker for finger vasoconstriction reflected by decreased signal amplitude and as a surrogate for autonomic and cortical arousals. Our aim was to study the effect of scoring arousals based on PWA on scoring of respiratory events in pediatric patients. Methods Ten polysomnograms for patients between the ages of 5-15 years who had apnea-hypopnea indices between 1 and 3 events/hour were identified. Patients with syndromes were excluded. A drop in PWA signal of at least 30% that lasted for 3 seconds was needed to identify subcortical/autonomic arousals. Arousals were rescored based on this criteria and subsequently respiratory events were rescored. Paired t-tests were employed to compare PSG indices scored with or without PWA incorporation. Results The sample of 10 children included 2 females, and the average age was 9.8 +/-3.1 years. Overall, polysomnography revealed an average total sleep time of 464.1 +/-25 mins, sleep efficiency of 92% +/-4.2, sleep latency of 19.6 +/-17.0 mins, rapid eye movement (REM) latency 143 +/-66 mins, N1 3.9% +/-2.0, N2 50.3% +/-12.0, N3 28.2% +/-9.1, REM 16.7% +/-4.0, and wakefulness after sleep onset (WASO) 18.1 +/-7.5 mins. Including arousals from PWA changes, respiratory indices significantly increased including total AHI (2.3 +/-0.7 vs 5.7 +/-2.1, p<0.001), obstructive AHI (1.45 +/-0.7 vs 4.8 +/-1.8, p<0.001), and RDI (2.36 +/-0.7 vs 7.6 +/-2.0, p<0.001). Likewise, total arousal index was significantly higher (8.7 +/-2.3 vs 29.4 +/-6.5, p<0.001). Conclusion Pulse wave amplitude is a useful marker for arousals that are not otherwise easily identified in pediatric polysomnography. This in turn would lead to a more accurate scoring of respiratory events and severity assessment of sleep disordered breathing. This likely will have clinical and therapeutic implications. Support None

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Yeboah, Kwame, Daniel A. Antwi, and Ben Gyan. "Arterial Stiffness in Nonhypertensive Type 2 Diabetes Patients in Ghana." International Journal of Endocrinology 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/6107572.

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Background. Increased arterial stiffness is an independent cardiovascular risk factor in diabetes patients and general population. However, the contribution of diabetes to arterial stiffness is often masked by coexistent obesity and hypertension. In this study, we assessed arterial stiffness in nonhypertensive, nonobese type 2 diabetes (T2DM) patients in Ghana.Methods. In case-control design, 166 nonhypertensive, nonobese participants, comprising 96 T2DM patients and 70 nondiabetes controls, were recruited. Peripheral and central blood pressure (BP) indices were measured, and arterial stiffness was assessed as aortic pulse wave velocity (PWVao), augmentation index (AIx), cardioankle vascular index (CAVI), and heart-ankle pulse wave velocity (haPWV).Results. With similar peripheral and central BP indices, T2DM patients had higher PWVao (8.3 ± 1versus7.8 ± 1.3,p=0.044) and CAVI (7.9 ± 1.2versus6.9 ± 0.7,p=0.021) than nondiabetic control. AIx and haPWV were similar between T2DM and nondiabetic controls. Multiple regression models showed that, in the entire study participants, the major determinants of PWVao were diabetes status, age, gender, systolic BP, and previous smoking status (β= 0.22, 0.36, 0.48, 0.21, and 0.25, resp.; allp<0.05); the determinants of CAVI were diabetes status, age, BMI, heart rate, HbA1c, total cholesterol, HDL cholesterol, and previous smoking status (β= 0.21, 0.38, 0.2, 0.18, 0.24. 0.2, −0.19, and 0.2, resp.; allp<0.05).Conclusion. Our findings suggest that nonhypertensive, nonobese T2DM patients have increased arterial stiffness without appreciable increase in peripheral and central pressure indices.

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Kohram, H., G. Mohammadi, and E. Dirandeh. "445 RELATIONSHIPS OF LUTEAL PHASE VARIABLES (PRIOR TO AI) WITH FOLLICULAR WAVES IN WATER BUFFALOES." Reproduction, Fertility and Development 22, no. 1 (2010): 379. http://dx.doi.org/10.1071/rdv22n1ab445.

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This study was done to consider relationships of luteal phase variables (prior to AI) with follicular waves. The estrous cycles of 15 buffaloes were synchronized with 2 i.m. injections of prostaglandin F2α given 11 days apart. The buffaloes were randomly assigned to 1 of 3 treatments. Buffaloes in the control treatment received no treatment, whereas G6 buffalos received a GnRH injection between Day 5 and 7 and G16 buffalos received a GnRH injection between Day 15 and 17 of the estrous cycle (estrus = Day 0). Daily, from estrus Day 0 to the next estrus Day 23, buffaloes had their ovaries scanned by ultrasound. Blood samples were collected by tail following each ultrasound examination from estrus until next estrus (estrus = 0). Concentrations of plasma progesterone were determined by radioimmunoassay kit. The limit of detection of the assay was 0.1 45 ng mL-1 and the intra- and interassay coeffients of variation were 7.4% and 9.2%, respectively. Data were analyzed by using PROC GLM of SAS (SAS Institute, Cary, NC, USA). For comparisons between groups, the 2-sample t-test was used for continuous traits, such as size of CL or hormone concentrations. Prospective comparisons of indices of progesterone indicated that the length of luteal lifespan was longer in 3-wave than in 2-wave buffaloes (P < 0.01). Plasma progesterone concentrations were similar at peak and measured as area under the curve on Day 5 through 17 preceding insemination in 2-wave (5.30 ± 0.40 ng mL-1) and 3-wave buffaloes (5.10 ± 0.20 ng mL-1). Length of the luteal phase (defined as from the day of estrus until the last day on which plasma progesterone remained >2 ng mL-1) was <2 days shorter in 2-wave buffaloes than in 3-wave buffaloes (15.20 ± 0.40 v. 17.10 ± 0.50 d; P < 0.05). In addition, the day of peak progesterone occurred earlier in 2-wave buffaloes (13.50 ± 0.30 v. 15.30 ± 0.70 d; P < 0.05).

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CURRAN, PETER A. "OBSERVATIONS OF PARTICLE ACCELERATION IN THE BLAST WAVES OF GAMMA-RAY BURSTS." International Journal of Modern Physics: Conference Series 08 (January 2012): 235–40. http://dx.doi.org/10.1142/s2010194512004655.

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The electron energy distribution index, p, is a fundamental parameter of the process by which electrons at shock fronts are accelerated to relativistic speeds and by which they radiate, via synchrotron emission. This acceleration process is applicable to a myriad of astronomical jet sources such as AGN, X-ray binaries and gamma-ray bursts (GRBs), as well as to particle acceleration in the solar wind and supernovae, and the acceleration of cosmic rays. The accurate measurement of the distribution of p is of fundamental importance to differentiate between the possible theories of electron acceleration at any relativistic shock front; there is division as to whether p has a universal value or whether it has a distribution, and if so, what that distribution is. Here one such source of synchrotron emission is examined: the blast waves of GRB afterglows observed by the Swift satellite. Within the framework of the GRB blast wave model, the constraints placed on the distribution of p by the observed X-ray spectral and temporal indices are examined and the distribution parametrized. The results show that the observed distribution of spectral indices is inconsistent with an underlying distribution of p composed of a single discrete value but consistent with a Gaussian distribution centred at p = 2.4 and having a width of 0.6. This finding disagrees with theoretical work that argues for a single, universal value of p, but also demonstrates that the width of the distribution is not as wide as has been suggested by some authors.

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Hani, Al Haddad, Paul B. Laursen, Ahmaidi Said, and Buchheit Martin. "Nocturnal Heart Rate Variability Following Supramaximal Intermittent Exercise." International Journal of Sports Physiology and Performance 4, no. 4 (December 2009): 435–47. http://dx.doi.org/10.1123/ijspp.4.4.435.

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Purpose:To assess the effect of supramaximal intermittent exercise on long-term cardiac autonomic activity, inferred from heart rate variability (HRV).Methods:Eleven healthy males performed a series of two consecutive intermittent 15-s runs at 95% VIFT (i.e., speed reached at the end of the 30-15 Intermittent Fitness Test) interspersed with 15 s of active recovery at 45% VIFT until exhaustion. Beat-to-beat intervals were recorded during two consecutive nights (habituation night and 1st night) before, 10 min before and immediately after exercise, as well as 12 h (2nd night) and 36 h (3rd night) after supramaximal intermittent exercise. The HRV indices were calculated from the last 5 min of resting and recovery periods, and the first 10 min of the first estimated slow wave sleep period.Results:Immediate post-supramaximal exercise vagal-related HRV indices were significantly lower than immediate pre-supramaximal exercise values (P < .001). Most vagal-related indices were lower during the 2nd night compared with the 1st night (eg, mean RR intervals, P = .03). Compared with the 2nd night, vagal-related HRV indices were significantly higher during the 3rd night. Variables were not different between the 1st and 3rd nights; however, we noted a tendency (adjusted effect size, aES) for an increased normalized high-frequency component (P = .06 and aES = 0.70) and a tendency toward a decreased low-frequency component (P = .06 and aES = 0.74).Conclusion:Results confirm the strong influence of exercise intensity on short- and long-term post exercise heart rate variability recovery and might help explain the high efficiency of supramaximal training for enhancing indices of cardiorespiratory fitness.

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Henry, Aiwuyo Osarume, Osarenkhoe Osaretin John, Umuerri Ejiroghene Ejiroghene, Aigbe Fredrick Fredrick, Atoe-Imagbe Osagioduwa Mike, Ogbomo Aisosa Aisosa, Okoke Eseoghene Unuwaje, Evbayekha O. Endurance, and Obasohan Austine Austine. "Correlation Between Left Atrial Indices and Left Ventricular Diastolic Function Among Hypertensive Patients." International Journal of Health Sciences 6, no. 1 (February 1, 2023): 16–20. http://dx.doi.org/10.47941/ijhs.1186.

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Purpose: To compare LA indices and cardiac indices among hypertensive with left ventricular diastolic dysfunction Methodology: It is an echocardiographic based descriptive cross-sectional study. A total of 200 hypertensive patients were recruited from the cardiology clinics using systematic sampling method. Results: The mean age of the study population was 58.7 ±13.96 (58.42±13.29 for Hypertensives) years while the median age was 59years.The female to male ratio was 1:6. Majority of the cases had isolated diastolic dysfunction n=149 (74.5%), thirty-six (18%) had normal diastolic and systolic functions while 7.5% had combined systolic and diastolic dysfunction (n=15). Left atrial maximum volume correlated significantly with E/E Prime (P= 0.003) and E/A Ratio (P= 0.003). While Left atrial pre-A wave volume (P=0.025), Left atrial diameter did not correlate with IVRT, E/E’, E/A ratio. Unique Contribution to Theory, Policy and Practice: Among the hypertensive patients E/E’ significantly correlated positively with all phasic LA volumes compared to E/A ratio. LV mass independently predicted all LA phasic volumes.

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