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Journal articles on the topic 'Systolic geometry'

Author: Grafiati

Published: 28 February 2024

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1

Redaelli, A., E. Di Martino, S. Mantero, A. Agazzi, E. Vangeri, A. Gamba, and R. Fumero. "Optimisation of a Stentless Valve Prosthesis Based on an Analytic Parametric Model of the Aortic Valve." International Journal of Artificial Organs 21, no. 3 (March 1998): 161–70. http://dx.doi.org/10.1177/039139889802100307.

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An analytical mathematical model of a stentless aortic valve has been implemented. The valve is characterised by a trileaflet geometry, cilindrical leaflets; the aortic root is schematised by a conical surface which includes the leaflet attachments. The model Is defined through six geometric parameters: the base radius, the valve height, the commissure radius, the leaflet radial, circumferential and attachment line lengths. Five performance indexes have been used to optimise the valve geometry, namely: the systolic area, the leaflet circumferential stress in diastole, the leaflet bending strain in systole and two bending angles related to the rotation of the leaflets from the diastolic to the systolic configuration. The sensitivity analysis is carried out which can identify the influence of each geometric parameter on the performance indexes adopted for the optimum valve design. The analysis of the results provides the geometric configuration which optimises the overall function of the valve throughout the cardiac cycle.

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2

Adebayo, Rasaaq A., Olaniyi J. Bamikole, Michael O. Balogun, Anthony O. Akintomide, Victor O. Adeyeye, Luqman A. Bisiriyu, Tuoyo O. Mene-Afejuku, Ebenezer A. Ajayi, and Olugbenga O. Abiodun. "Echocardiographic Assessment of Left Ventricular Geometric Patterns in Hypertensive Patients in Nigeria." Clinical Medicine Insights: Cardiology 7 (January 2013): CMC.S12727. http://dx.doi.org/10.4137/cmc.s12727.

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Left ventricular (LV) hypertrophy is an important predictor of morbidity and mortality in hypertensive patients, and its geometric pattern is a useful determinant of severity and prognosis of heart disease. Studies on LV geometric pattern involving large number of Nigerian hypertensive patients are limited. We examined the LV geometric pattern in hypertensive patients seen in our echocardiographic laboratory. A two-dimensional, pulsed, continuous and color flow Doppler echocardiographic evaluation of 1020 consecutive hypertensive patients aged between 18 and 91 years was conducted over an 8-year period. LV geometric patterns were determined using the relationship between the relative wall thickness and LV mass index. Four patterns of LV geometry were found: 237 (23.2%) patients had concentric hypertrophy, 109 (10.7%) had eccentric hypertrophy, 488 (47.8%) had concentric remodeling, and 186 (18.2%) had normal geometry. Patients with concentric hypertrophy were significantly older in age, and had significantly higher systolic blood pressure (BP), diastolic BP, and pulse pressure than those with normal geometry. Systolic function index in patients with eccentric hypertrophy was significantly lower than in other geometric patterns. Doppler echocardiographic parameters showed some diastolic dysfunction in hypertensive patients with abnormal LV geometry. Concentric remodeling was the most common LV geometric pattern observed in our hypertensive patients, followed by concentric hypertrophy and eccentric hypertrophy. Patients with concentric hypertrophy were older than those with other geometric patterns. LV systolic function was significantly lower in patients with eccentric hypertrophy and some degree of diastolic dysfunction were present in patients with abnormal LV geometry.

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3

Katz, Mikhail G., and Tahl Nowik. "A systolic inequality with remainder in the real projective plane." Open Mathematics 18, no. 1 (August 24, 2020): 902–6. http://dx.doi.org/10.1515/math-2020-0050.

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Abstract The first paper in systolic geometry was published by Loewner’s student P. M. Pu over half a century ago. Pu proved an inequality relating the systole and the area of an arbitrary metric in the real projective plane. We prove a stronger version of Pu’s systolic inequality with a remainder term.

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4

Babenko, Ivan, Florent Balacheff, and Guillaume Bulteau. "Systolic geometry and simplicial complexity for groups." Journal für die reine und angewandte Mathematik (Crelles Journal) 2019, no. 757 (December 1, 2019): 247–77. http://dx.doi.org/10.1515/crelle-2017-0041.

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AbstractTwenty years ago Gromov asked about how large is the set of isomorphism classes of groups whose systolic area is bounded from above. This article introduces a new combinatorial invariant for finitely presentable groups called simplicial complexity that allows to obtain a quite satisfactory answer to his question. Using this new complexity, we also derive new results on systolic area for groups that specify its topological behaviour.

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5

Dehne, F., A. L. Hassenklover, J. R. Sack, and N. Santoro. "Computational geometry algorithms for the systolic screen." Algorithmica 6, no. 1-6 (June 1991): 734–61. http://dx.doi.org/10.1007/bf01759069.

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6

Dranishnikov, Alexander N., Mikhail G. Katz, and Yuli B. Rudyak. "Cohomological dimension, self-linking, and systolic geometry." Israel Journal of Mathematics 184, no. 1 (July 31, 2011): 437–53. http://dx.doi.org/10.1007/s11856-011-0075-8.

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7

Katz, M. "Local calibration of mass and systolic geometry." Geometric And Functional Analysis 12, no. 3 (August 1, 2002): 598–621. http://dx.doi.org/10.1007/s00039-002-8259-3.

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8

Vatnikov, Yury A., Andrey A. Rudenko, Boris V. Usha, Evgeny V. Kulikov, Elena A. Notina, Irina A. Bykova, Nadiya I. Khairova, Irina V. Bondareva, Victor N. Grishin, and Andrey N. Zharov. "Left ventricular myocardial remodeling in dogs with mitral valve endocardiosis." April-2020 13, no. 4 (2020): 731–38. http://dx.doi.org/10.14202/vetworld.2020.731-738.

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Background and Aim: Left ventricular myocardial remodeling could play an important role in the progression of chronic heart failure (CHF) syndrome in dogs with mitral valve endocardiosis. The aim of this study was to evaluate the left ventricular myocardial remodeling in dogs with mitral valve endocardiosis and to study the dependence of the incidence of this pathological phenomenon on the functional class (FC) of progression of the CHF syndrome. Materials and Methods: A total of 108 afflicted dogs and 36 clinically healthy dogs were examined using transthoracic echocardiography. The following structural and geometric parameters of the left ventricular remodeling were evaluated: Myocardial mass and its index, sphericity index at the end of systole and diastole, end-systolic and end-diastolic relative wall thickness, and integral remodeling index. Results: In all clinically healthy dogs, a normal type of the left ventricular chamber geometry was revealed, whereas, in dogs with mitral valve endocardiosis, the normal geometry of the left ventricle occurred in 56.4%, eccentric hypertrophy in 24.1%, concentric remodeling in 10.2%, and concentric hypertrophy in 9.3% of the cases. In patients with endocardiosis, there was no dilatation type of cardiac remodeling observed. Conclusion: When compared to the clinically healthy animals, the dogs with mitral valve endocardiosis presented with indicators of structural and geometric remodeling, such as increased myocardial mass, myocardial mass index, and sphericity index at the end of systole and diastole, as well as relatively reduced integral systolic index of remodeling and systolic relative thickness of the walls of the heart. The parameters of the left ventricular myocardial remodeling correlated significantly with the FC of CHF syndrome.

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9

Batra, S., and K. Rakusan. "Capillary length, tortuosity, and spacing in rat myocardium during cardiac cycle." American Journal of Physiology-Heart and Circulatory Physiology 263, no. 5 (November 1, 1992): H1369—H1376. http://dx.doi.org/10.1152/ajpheart.1992.263.5.h1369.

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Microvascular geometry was evaluated in rat left ventricular midmyocardium (male Sprague-Dawley, n = 14), arrested in systole (S) or diastole (D), by bolus injections of CaCl2 or KCl, respectively. The histological method employed in this study allowed for the visualization of capillary pathways from arteriole to venule. Capillary length, as directly measured from terminal arteriole to collecting venule, was not significantly different between S and D groups, averaging 606 +/- 15 microns (pooled mean +/- SE). The capillary length tortuosity, defined as the ratio of the capillary length to the direct arteriovenous distance, was significantly increased in systolic-arrested hearts (S = 1.31 +/- 0.03; D = 1.18 +/- 0.02, P < 0.01). At the level of individual capillary segments, however, there was no increase in tortuosity in systolic-arrested hearts (S = 1.17 +/- 0.03; D = 1.16 +/- 0.02). Intercapillary spacing was significantly more uniform in systolic-arrested hearts. These data suggest that in systole, capillary length and tortuosity are generally preserved, and capillary spacing is more uniform, serving to maintain geometric conditions for oxygen supply during the cardiac cycle.

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10

Osajda, Damian, and Piotr Przytycki. "Boundaries of systolic groups." Geometry & Topology 13, no. 5 (August 17, 2009): 2807–80. http://dx.doi.org/10.2140/gt.2009.13.2807.

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11

Umeo, H., and T. Asano. "Systolic algorithms for computational geometry problems — A survey." Computing 41, no. 1-2 (March 1989): 19–40. http://dx.doi.org/10.1007/bf02238727.

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12

Guth, Larry. "Notes on Gromov’s systolic estimate." Geometriae Dedicata 123, no. 1 (January 4, 2007): 113–29. http://dx.doi.org/10.1007/s10711-006-9111-y.

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13

Babenko, I. K. "Löwner's conjecture, the Besicovitch barrel, and relative systolic geometry." Sbornik: Mathematics 193, no. 4 (April 30, 2002): 473–86. http://dx.doi.org/10.1070/sm2002v193n04abeh000641.

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14

Stokke, Thomas M., Nina E. Hasselberg, Marit K. Smedsrud, Sebastian I. Sarvari, Kristina H. Haugaa, Otto A. Smiseth, Thor Edvardsen, and Espen W. Remme. "Geometry as a Confounder When Assessing Ventricular Systolic Function." Journal of the American College of Cardiology 70, no. 8 (August 2017): 942–54. http://dx.doi.org/10.1016/j.jacc.2017.06.046.

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15

Katz, M., and A. Suciu. "Systolic freedom of loop space." Geometric and Functional Analysis 11, no. 1 (April 2001): 60–73. http://dx.doi.org/10.1007/pl00001672.

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16

Chinali, Marcello, Laura Lucchetti, Agnese Ricotta, Claudia Esposito, Carolina D’Anna, Gabriele Rinelli, Francesco Emma, and Laura Massella. "Cardiac Abnormalities in Children with Autosomal Recessive Polycystic Kidney Disease." Cardiorenal Medicine 9, no. 3 (2019): 180–89. http://dx.doi.org/10.1159/000496473.

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Background: No previous study has defined the prevalence of cardiac geometric and mechanical function abnormalities through the analysis of advanced echocardiographic parameters in children with autosomal recessive polycystic kidney disease (ARPKD). Aim: The purpose of this study was to evaluate cardiac geometry and function through advanced echocardiography in a well-characterized sample of pediatric patients with ARPKD. Methods: Standard echocardiograms were obtained in 27 children with ARPKD (0–18 years) and in 88 healthy children of similar age, gender distribution, and body build. Left ventricular (LV) hypertrophy was defined as LV mass > 45g/(m2.16 + 0.09) and cardiac remodeling was defined by age-adjusted relative wall thickness (RWT). Systolic function was assessed by ejection fraction, midwall fractional shortening (mFS), and global longitudinal (GLS) and circumferential strain (GCS). Results: Patients with ARPKD exhibited a higher LV mass index as compared to controls, and a more concentric LV geometry (both p < 0.001). Accordingly, the prevalence of abnormal LV geometry was significantly higher in ARPKD (33 vs. 0%; p < 0.005). No differences could be observed in the two groups for ejection fraction or GLS (both p = n.s.), while a significantly lower mFS (p < 0.05) as well as GCS (p < 0.001) could be observed. In the analysis of covariance, both LV mass index and RWT remained significantly higher in the ARPKD group, while mFS and GCS remained significantly lower (all p < 0.05). The prevalence of subclinical systolic dysfunction was significantly higher in patients with ARPKD as compared with control subjects (33 vs. 0%; p < 0.001). Conclusions: Children with ARPKD show significantly impaired cardiac phenotype, characterized by high rates of LV abnormal geometry paired with systolic mechanical dysfunction.

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17

Syvolap, V. V., and A. O. Bohun. "Types of the left ventricle geometry and changes in functional parameters of the heart in patients with atrial fibrillation." Zaporozhye Medical Journal 25, no. 5 (September 28, 2023): 383–90. http://dx.doi.org/10.14739/2310-1210.2023.5.282107.

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Aim. To study the features of the left ventricle remodeling and changes in its functional signs in patients with atrial fibrillation (AF). Materials and methods. In total, 2423 patients aged from 18 to 94 years (mean age – 57.9 ± 16.4 years), 51 % men, with pathologies of the cardiovascular and respiratory systems and patients without diagnosed diseases of cardiovascular system were enrolled in the study. Echocardiography was performed on an Esaote MyLab Seven device (Italy) according to generally accepted rules. The indicators of systolic and diastolic, valvular functions, the distribution of patients according to four classic types of the left ventricular geometry were studied. Statistical analysis was performed using the Statistica 13.0 software package for Windows. Statistically significant differences were calculated using the Mann–Whitney U test, Pearson’s χ2 test, Kruskal–Wallis test. A level of p < 0.05 was taken to indicate statistical significance. Results. The prevalence of AF in the group of normal geometry was 6.5 %, concentric remodeling – 11.8 %, eccentric hypertrophy – 17.4 %, concentric hypertrophy – 21.7 %. Left ventricular hypertrophy was diagnosed in 56.2 % of patients with AF (32.0 % – eccentric hypertrophy, 27.8 % – concentric hypertrophy), while in the patient group without AF, left ventricular hypertrophy was detected in only 33.9 % of the examined (20.4 % – eccentric hypertrophy, 13.5 % – concentric hypertrophy). In groups of concentric and eccentric hypertrophy, the patients were older, there was a higher prevalence of mitral, aortic, tricuspid valve regurgitation, and lower indicators of systolic function (EF, TEI, S’), diastolic function (e’med) than those in groups with normal geometry and concentric remodeling. In 29.3 % of patients with AF, the geometry of the left ventricle remained normal. Conclusions. The prevalence of AF increased according to the geometric patterns of the left ventricular remodeling with the highest rates in the groups of eccentric and concentric hypertrophy, which were also associated with worse indicators of systolic, diastolic, and valve functions.

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18

Januszkiewicz, Tadeusz, and Jacek Świątkowski. "Filling invariants of systolic complexes and groups." Geometry & Topology 11, no. 2 (May 10, 2007): 727–58. http://dx.doi.org/10.2140/gt.2007.11.727.

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19

Osajda, Damian. "Ideal boundary of 7–systolic complexes and groups." Algebraic & Geometric Topology 8, no. 1 (February 8, 2008): 81–99. http://dx.doi.org/10.2140/agt.2008.8.81.

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20

Ryu, Hoil. "Stable systolic category of the product of spheres." Algebraic & Geometric Topology 11, no. 2 (March 25, 2011): 983–99. http://dx.doi.org/10.2140/agt.2011.11.983.

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21

Sabourau, Stéphane, and Zeina Yassine. "A systolic-like extremal genus two surface." Journal of Topology and Analysis 11, no. 03 (September 2019): 721–38. http://dx.doi.org/10.1142/s1793525319500298.

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It is known that the genus two surface admits a piecewise flat metric with conical singularities which is extremal for the systolic inequality among all nonpositively curved metrics. We prove that this piecewise flat metric is also critical for slow metric variations, without curvature restrictions, for another type of systolic inequality involving the lengths of the shortest noncontractible loops in different free homotopy classes.

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22

Hemmati, Rohola, Mojgan Gharipour, Hasan Shemirani, Alireza Khosravi, and Elham Khosravi. "Urine Albumin to Creatinine Ratio and Echocardiographic Left Ventricular Structure and Function in Patients with Essential Hypertension." American heart hospital journal 9, no. 2 (2011): 90. http://dx.doi.org/10.15420/ahhj.2011.9.2.90.

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Background:Appearance of microalbuminuria, particularly in patients with hypertension, might be associated with a higher prevalence of left ventricular (LV) dysfunction and geometric abnormalities. This study was undertaken to determine whether high urine albumin to creatinine ratio (UACR) as a sensitive marker for microalbuminuria can be associated with LV hypertrophy (LVH) and systolic and diastolic LV dysfunction.Methods:The study population consisted of 125 consecutive patients with essential uncomplicated hypertension. Urine albumin and creatinine concentration was determined by standard methods. LVH was defined as a LV mass index >100 g/m2 of body surface area in women and >130 g/m2 in men. Echocardiographic LV systolic and diastolic parameters were measured.Results:The prevalence of microalbuminuria in patients with essential hypertension was 5.6 %. UACR was significantly no different in patients with LVH than in patients with normal LV geometry (21.26 ± 31.55 versus 17.80 ± 24.52 mg/mmol). No significant correlation was found between UACR measurement and systolic and diastolic function parameters, including early to late diastolic peak velocity (E/A) ratio (R=-0.192, p=0.038), early diastolic peak velocity to early mitral annulus velocity (E/E') ratio (R=-0.025, p=0.794), LV ejection fraction (R=0.008, p=0.929), and LV mass (R=-0.132, p=0.154). According to the receiver operator characteristic (ROC) curve analysis, UACR measurement was not an acceptable indicator of LVH with areas under the ROC curves 0.514 (95 % confidence interval 0.394–0.634). The optimal cut-off value for UACR for predicting LVH was identified at 9.4, yielding a sensitivity of 51.6 % and a specificity of 48.3 %.Conclusion:In patients with uncomplicated essential hypertension, abnormal systolic and diastolic LV function and geometry cannot be effectively predicted by the appearance of microalbuminuria.

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23

Elsner, Tomasz. "Flats and the flat torus theorem in systolic spaces." Geometry & Topology 13, no. 2 (January 1, 2009): 661–98. http://dx.doi.org/10.2140/gt.2009.13.661.

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24

Nazir, Fauzia, Tahir Iqbal, Javeria Kamran, Tariq Hussain Khattak, Anum Fatima, Aatika Habib, and Saleh Kaleem. "FREQUENCY AND RISK FACTORS OF LEFT VENTRICULAR GEOMETRIC ABNORMALITIES IN HYPERTENSIVE PATIENTS: A STUDY BASED ON THE UPDATED CLASSIFICATION SYSTEM OF LEFT VENTRICULAR GEOMETRY." Pakistan Armed Forces Medical Journal 70, Suppl-4 (January 5, 2021): S695–700. http://dx.doi.org/10.51253/pafmj.v70isuppl-4.6002.

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Objective: To determine the association between cardiovascular risk factors and the abnormalities of left ventricular geometric abnormalities. Study Design: Prospective cross-sectional, single centered study. Place and Duration of Study: Armed Forces Institute of Cardiology, Rawalpindi, from Jun 2018 to Dec 2018. Methodology: This study permission was sought from hospital ethics committee. Written informed consent was taken from participants of study. Particulars of all the patients who meet the inclusion were included i.e., 351 hypertensive. Results: Left ventricular geometric abnormalities were detected in 321 subjects (91%), wherein concentric non dilated left ventricular hypertrophy is the most common left ventricular geometric abnormality (39%). Elevated systolic blood pressure and diabetes mellitus were positively associated with concentric left ventricular remodeling, whereas body mass index and chronic kidney disease were inversely associated with concentric abnormalities. systolic blood pressure and diabetes mellitus, chronic kidney disease, large WC were positively associated with eccentric dilated left ventricular hypertrophy, while body mass index, duration of hypertension, MS were inversely associated with eccentric dilated left ventricular hypertrophy. Elevated systolic blood pressure was the strongest risk factor for eccentric dilated left ventricular hypertrophy. Large WC, systolic blood pressure and diabetes mellitus were positively associated with concentric left ventricular hypertrophy, whereas body mass index was negatively associated with concentric left ventricular hypertrophy. Conclusion: Appropriate risk factor management and compliance can prevent left ventricular geometric abnormalities hence poorer outcomes in our population

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25

Barabash, O. S., Yu A. Ivaniv, I. M. Tumak, and Y. R. Barabash. "The effect of left ventricular remodeling on the longitudinal myocardial kinetics of both heart ventricles in patients with arterial hypertension and cardiovascular risk factors." Ukrainian Journal of Cardiology 26, no. 3 (July 30, 2019): 27–34. http://dx.doi.org/10.31928/1608-635x-2019.3.2734.

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The aim – to study the longitudinal kinetics of the left, right ventricles and interventricular septum (IVS), depending on the type of left ventricular (LV) remodeling in patients with arterial hypertension (AH) in combination with additional cardiovascular risk factors with preserved LV contractility, as well as to determine the correlation of changes in the right ventricular systolic and diastolic parameters estimated with the tissue pulsed-wave Doppler imaging (TDI) with the same indices of the LV and IVS. Materials and methods. The study included 71 patients (average age – 54) with essential AH (68 % men) with a normal LV ejection fraction. The patients had the obese stage 1, combined hyperlipidemia, 29.6 % of patients had type II diabetes, 33.8 % were smokers. The patients were distributed into 4 groups depending on the types of remodeling: 1 – normal geometry (12.7 %); 2 – concentric remodeling (47.9 %); 3 – concentric hypertrophy (35.2 %); 4 – eccentric hypertrophy (4.2 %). TDI of the left and right ventricles and IVS was performed, systolic and diastolic TDI indices were determined, and the index of isovolumic myocardial acceleration (IVA) was calculated for the right ventricle (RV). Results and discussion. The type of LV concentric hypertrophy negatively affects the longitudinal myocardial kinetics of LV and IVS in the study group. The early diastolic velocity Em and the systolic velocity Sm were significantly decreased for the LV and IVS, the late diastolic velocity Am was decreased for the IVS and the E/Em for LV ratio was notably increased. Among the diastolic RV TDI indices only the deceleration time DTEm was significantly longer in LV concentric remodeling and concentric hypertrophy, than in its normal geometry. The IVA index was decreased in changing the type of LV geometry from normal to eccentric hypertrophy, indicating worsening of the RV longitudinal myocardial systolic function. There was a close correlation between diastolic and systolic TDI indices of the RV and IVS, which potentially indicated the importance of IVS in the mechanism of interventricular interaction and its effect on the RV function. The reliable dependence of systolic and diastolic RV TDI indices on the LV contractility was established. Conclusions. The type of LV remodeling, especially concentric hypertrophy, negatively affects the longitudinal myocardial kinetics of both ventricles in patients with AH in combination with additional cardiovascular risk factors. IVA can be a sensitive diagnostic criterion in the detection of early myocardial disorders of the RV systolic function with the changes of the LV geometry in this category of patients. Indices of RV longitudinal myocardial kinetics are closely dependent on changes in the function of IVS, which has a leading role in the formation of interventricular interaction.

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26

Tareq, Md Nur Uddin, Chaudhury Meshkat Ahmed, Sohel Mahmud, and KMHS Sirajul Haque. "Assessment of left Ventricular Longitudinal Function in Different Hypertensive Left Ventricular Geometry." University Heart Journal 17, no. 1 (December 21, 2020): 31–37. http://dx.doi.org/10.3329/uhj.v17i1.50877.

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Background: Hypertension remains as the major risk factor for cardiovascular diseases. Hypertensive left ventricular hypertrophy was shown to be associated with increased morbidity and mortality. Left ventricular radial function (Ejection fraction) tends to remain normal in hypertensive patients, particular attention should be given to longitudinal function along with diastolic function. Left ventricular longitudinal function may vary across different hypertensive LV geometry with different prognosis. Results: Of the total 214 study subjects, 109 (50.9%) were Cases and 105 (49.1%) were Controls. The mean ages of cases and controls were 52.66 (± 10.96) and 50.21 (± 10.91) years respectively. Left ventricular ejection function (LVEF) was almost identical in both groups [mean LVEF in case 68.7 % (± 6.9) Vs control 68.7(± 5.4), (p 0.947)]. Among the cases 43% had concentric hypertrophy (CH), 20% had eccentric hypertrophy (EH), 20% had concentric remodeling (CR), while normal geometry constituted the least 16.5%. Mean systolic mitral annular velocity (Vs) and mean early diastolic velocity (Ve) assesed by pulse wave tissue doppler imaging were observed to be significantly decreased in cases compared to their control counterpart (11.46 ± 1.26 vs. 15.41 ± 1.00 cm/sec, p < 0.001 and 13.80 ± 2.37 vs. 16.76 ± 2.67 cm/sec, p < 0.001. There was significant reduction of Vs in concentric hypertrophy and eccentric hypertrophy (11.31 ± 1.41 and 12.27 ± 2.14). (p <0.001 and <0.005). Among cases 55 (50.5%) and among controls 17 (16%) had diastolic dysfunction. Mean systolic mitral annular velocity (Vs) in patients with diastolic dysfunction (12.42 ± 1.90 cm/sec) was significantly lower than that in patients without diastolic dysfunction (13.86 ± 2.30 cm/sec) (p < 0.001). Conclusion: Radial function (LVEF) remains normal in patients with systemic hypertension as compared to controls. LVH is common among hypertensive and concentric hypertrophy is the commonest geometry. LV longitudinal systolic function as assessed by systolic mitral annular velocity (Vs) by DTI was significantly reduced in hypertensives and CH is the most severely affected with EH at intermediate risk. Diastolic dysfunction is also common but almost alaways accompanied by impairment of LV longitudinal systolic function. University Heart Journal Vol. 17, No. 1, Jan 2021; 31-37

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27

Brunnbauer, Michael. "Homological Invariance For Asymptotic Invariants and Systolic Inequalities." Geometric and Functional Analysis 18, no. 4 (August 4, 2008): 1087–117. http://dx.doi.org/10.1007/s00039-008-0677-4.

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28

Xu, Chun, Clay J. Brinster, Arminder S. Jassar, Mathieu Vergnat, Thomas J. Eperjesi, Robert C. Gorman, Joseph H. Gorman, and Benjamin M. Jackson. "A novel approach to in vivo mitral valve stress analysis." American Journal of Physiology-Heart and Circulatory Physiology 299, no. 6 (December 2010): H1790—H1794. http://dx.doi.org/10.1152/ajpheart.00370.2010.

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Three-dimensional (3-D) echocardiography allows the generation of anatomically correct and time-resolved geometric mitral valve (MV) models. However, as imaged in vivo, the MV assumes its systolic geometric configuration only when loaded. Customarily, finite element analysis (FEA) is used to predict material stress and strain fields rendered by applying a load on an initially unloaded model. Therefore, this study endeavors to provide a framework for the application of in vivo MV geometry and FEA to MV physiology, pathophysiology, and surgical repair. We hypothesize that in vivo MV geometry can be reasonably used as a surrogate for the unloaded valve in computational (FEA) simulations, yielding reasonable and meaningful stress and strain magnitudes and distributions. Three experiments were undertaken to demonstrate that the MV leaflets are relatively nondeformed during systolic loading: 1) leaflet strain in vivo was measured using sonomicrometry in an ovine model, 2) hybrid models of normal human MVs as constructed using transesophageal real-time 3-D echocardiography (rt-3DE) were repeatedly loaded using FEA, and 3) serial rt-3DE images of normal human MVs were used to construct models at end diastole and end isovolumic contraction to detect any deformation during isovolumic contraction. The average linear strain associated with isovolumic contraction was 0.02 ± 0.01, measured in vivo with sonomicrometry. Repeated loading of the hybrid normal human MV demonstrated little change in stress or geometry: peak von Mises stress changed by <4% at all locations on the anterior and posterior leaflets. Finally, the in vivo human MV deformed minimally during isovolumic contraction, as measured by the mean absolute difference calculated over the surfaces of both leaflets between serial MV models: 0.53 ± 0.19 mm. FEA modeling of MV models derived from in vivo high-resolution truly 3-D imaging is reasonable and useful for stress prediction in MV pathologies and repairs.

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29

Blufstein, Martín Axel, and Elías Minian. "Strictly systolic angled complexes and hyperbolicity of one-relator groups." Algebraic & Geometric Topology 22, no. 3 (August 25, 2022): 1159–75. http://dx.doi.org/10.2140/agt.2022.22.1159.

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30

Benedetti, Gabriele, and Jungsoo Kang. "On a systolic inequality for closed magnetic geodesics on surfaces." Journal of Symplectic Geometry 20, no. 1 (2022): 99–134. http://dx.doi.org/10.4310/jsg.2022.v20.n1.a3.

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31

Sabourau, Stéphane. "Systolic volume of hyperbolic manifolds and connected sums of manifolds." Geometriae Dedicata 127, no. 1 (August 22, 2007): 7–18. http://dx.doi.org/10.1007/s10711-007-9146-8.

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Wadile, Santosh, Ejaz A. Sheriff, and Kothandam Sivakumar. "In congenitally corrected transposition of great arteries following Fontan surgery, a left ventricle with suprasystemic systolic and high end-diastolic pressures paradoxically preserves right ventricular and tricuspid valve function." Cardiology in the Young 29, no. 12 (October 31, 2019): 1522–23. http://dx.doi.org/10.1017/s1047951119002324.

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AbstractSystemic right ventricular function in congenitally corrected transposition depends on septal geometry. Suprasystemic left ventricular systolic pressures and high end-diastolic pressures after Fontan surgery paradoxically preserve right ventricular function.

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Haber, Idith, Dimitris N. Metaxas, Tal Geva, and Leon Axel. "Three-dimensional systolic kinematics of the right ventricle." American Journal of Physiology-Heart and Circulatory Physiology 289, no. 5 (November 2005): H1826—H1833. http://dx.doi.org/10.1152/ajpheart.00442.2005.

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The right ventricle (RV) of the heart is responsible for pumping blood to the lungs. Its kinematics are not as well understood as that of the left ventricle (LV) due to its thin wall and asymmetric geometry. In this study, the combination of tagged MRI and three-dimensional (3-D) image-processing techniques was used to reconstruct 3-D RV-LV motion and deformation. The reconstructed models were used to quantify the 3-D global and local deformation of the ventricles in a set of normal subjects. When compared with the LV, the RV exhibited a similar twisting pattern, a more longitudinal strain pattern, and a greater amount of displacement.

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Bekakos, M. P., and D. J. Evans. "A ‘rotating’ and ‘folding’ algorithm using a two-dimensional ‘systolic’ communication geometry." Parallel Computing 4, no. 2 (April 1987): 221–28. http://dx.doi.org/10.1016/0167-8191(87)90055-x.

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Picca, M., and F. Agozzino. "LEFT CARDIAC GEOMETRY AND FUNCTION IN ISOLATED SYSTOLIC HYPERTENSION: INFLUENCE OF GENDER." Journal of Hypertension 29 (June 2011): e356. http://dx.doi.org/10.1097/00004872-201106001-01039.

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Gunadi, Johan, Starry Homenta Rampengan, Janry Antonius Pangemanan, Agnes Lucia Panda, Nancy Lampus, and Hasjim Hasbullah. "Correlation between Suppression of Tumorigenicity-2 with Left Ventricular Geometry, Left Ventricular Ejection Fraction and Quality of Life in Systolic Heart Failure Patients." Indonesian Biomedical Journal 12, no. 3 (September 5, 2020): 233–8. http://dx.doi.org/10.18585/inabj.v12i3.948.

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BACKGROUND: Heart failure (HF) is a clinical syndrome caused by structural or functional cardiac disorders and is the final stage of every heart disease, marked by decreased functional capacity and patients’ quality of life (QoL). Suppression of tumorigenicity-2 (ST2) is a biomarker depicting heart fibrosis and remodeling that altered left ventricular geometry, which in turn decreases left ventricular contractility, decreases functional capacity, and ultimately affects the QoL of the HF patient.METHODS: An observational study was conducted with a cross-sectional approach involving 60 patients with systolic heart failure. Left ventricular geometry, left ventricular ejection fraction (LVEF), ST2 level, and other biomarkers were examined, continued by QoL assessment.RESULTS: The ST2 level (33.25±23.55 ng/mL) was negatively correlated with LVEF (r=-0.257; p=0.024) and was positively correlated with QoL (r=0.255; p=0.05). The LVEF was negatively correlated with QoL (r=-0.224; p=0.031). However, no significant correlation was found between left ventricular geometry with ST2 level or patients’ QoL.CONCLUSION: Elevated ST2 levels are correlated with decreased LVEF and worse QoL in systolic heart failure subjects. Therefore, ST2 together with LVEF can be used as prognostic tools for patients with HF.KEYWORDS: heart failure, ST2, left ventricular geometry, left ventricular ejection fraction, quality of life

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Crepaz, Roberto, Roberto Cemin, Cristina Romeo, Edoardo Bonsante, Lino Gentili, Diego Trevisan, Walter Pitscheider, and Giovanni Stellin. "Factors affecting left ventricular remodelling and mechanics in the long-term follow-up after successful repair of aortic coarctation." Cardiology in the Young 15, no. 2 (March 2005): 160–67. http://dx.doi.org/10.1017/s104795110500034x.

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Aims: To identify factors predisposing to abnormal left ventricular geometry and mechanics in 52 patients after successful repair of aortic coarctation. Methods and results: We evaluated left ventricular remodelling, systolic midwall mechanics, and isthmic gradient by echo-Doppler, systemic blood pressure at rest/exercise and by ambulatory blood pressure monitoring, and the aortic arch by magnetic resonance imaging. Echocardiographic findings were compared with those of 142 controls. The patients with aortic coarctation showed an increased indexed left ventricular end-diastolic volume, increased mass index, increased ratio of mass to volume and systolic chamber function. The contractility, estimated at midwall level, was increased in 21 percent of the patients. In 26 (50 percent) of the patients, we found abnormal left ventricular geometry, with 9 percent showing concentric remodelling, 33 percent eccentric hypertrophy, and 8 percent concentric hypertrophy. These patients were found to be older, underwent a later surgical repair, and to have higher systolic blood pressures at rest and exercise as well as during ambulatory monitoring. The relative mural thickness and mass index of the left ventricle showed a significant correlation with different variables on uni- and multivariate analysis. Age and diastolic blood pressure at rest are the only factors associated with abnormal left ventricular remodelling. Conclusions: Patients who have undergone a seemingly successful surgical repair of aortic coarctation may have persistently abnormal geometry with a hyperdynamic state of the left ventricle. This is more frequent in older patients, and in those with higher diastolic blood pressures.

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Fukaya, Tomohiro, and Shin-ichi Oguni. "A coarse Cartan–Hadamard theorem with application to the coarse Baum–Connes conjecture." Journal of Topology and Analysis 12, no. 03 (November 14, 2018): 857–95. http://dx.doi.org/10.1142/s1793525319500675.

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We establish a coarse version of the Cartan–Hadamard theorem, which states that proper coarsely convex spaces are coarsely homotopy equivalent to the open cones of their ideal boundaries. As an application, we show that such spaces satisfy the coarse Baum–Connes conjecture. Combined with the result of Osajda–Przytycki, it implies that systolic groups and locally finite systolic complexes satisfy the coarse Baum–Connes conjecture.

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Nabutovsky, Alexander. "Linear bounds for constants in Gromov’s systolic inequality and related results." Geometry & Topology 26, no. 7 (December 31, 2022): 3123–42. http://dx.doi.org/10.2140/gt.2022.26.3123.

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AJIBARE, ADEOLA, Oluwaseye Oladimeji, Ayoola ODEYEMI, Abisola Iyayi, Alaba Oladimeji, Olufemi Ojo, Alaba Adebola, Jacob Awobusuyi, and Adebowale Adekoya. "LEFT VENTRICULAR GEOMETRY AMONG CHRONIC KIDNEY DISEASE PATIENTS: THE ROLE OF ANEMIA." Medical and Health Science Journal 7, no. 01 (August 28, 2023): 30–40. http://dx.doi.org/10.33086/mhsj.v7i01.3842.

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BACKGROUND: Anaemia and abnormal left ventricular (LV) geometric pattern are common findings in Chronic Kidney disease (CKD) patients. OBJECTIVES: To assess LV geometric pattern and its relationship with anaemia among CKD patients. METHODS: A cross sectional study of 163 subjects (102 and 61 CKD subjects with and without anaemia respectively). Echocardiography determined the LV geometric pattern while packed cell volume (PCV) levels determined anaemia. RESULTS: The mean age of subjects with and without anaemia was 54.04 ± 14.47 and 54.92 ± 15.67 years respectively (p = 0.717) while the prevalence of LVH among the two groups was 68.8% and 57.9% respectively (p = 0.174). The most frequent LV geometry in both groups was concentric LVH (53.8% and 43.9% respectively). Prevalence of LV systolic dysfunction was 45%, higher among anaemic subjects (58(61.7%) vs 10(17.5%)) p < 0.001. There was a strong negative correlation between PCV and left ventricular mass index (r = -0.345, p = 0.001) among anaemic subjects, but weak positive correlation among patients without anaemia (r = 0.001, p = 0.993). CONCLUSION: Anaemic CKD patients had a high prevalence of abnormal LV geometry with significant contribution from anaemia. Early management of anaemia may thus improve cardiovascular outcomes.

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Vidal, Pablo, Francisco Luna, and Enrique Alba. "Systolic neighborhood search on graphics processing units." Soft Computing 18, no. 1 (April 7, 2013): 125–42. http://dx.doi.org/10.1007/s00500-013-1041-7.

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Nielsen, Sten Lyager, Hans Nygaard, Lars Mandrup, Arnold A. Fontaine, J. Michael Hasenkam, Shengqui He, and Ajit P. Yoganathan. "Mechanism of Incomplete Mitral Leaflet Coaptation—Interaction of Chordal Restraint and Changes in Mitral Leaflet Coaptation Geometry." Journal of Biomechanical Engineering 124, no. 5 (September 30, 2002): 596–608. http://dx.doi.org/10.1115/1.1500741.

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Clinically observed incomplete mitral leaflet coaptation was reproduced in vitro by altering the balance of the chordal tethering and chordal coapting force components. Mitral leaflet coaptation geometry was distorted by changes of the spatial relations between the papillary muscles and the mitral valve as well as hemodynamics. Mitral leaflet malalignment was accentuated by a redistribution of the chordal tethering and coapting force components. For the overall assessment of systolic mitral leaflet configuration in functional mitral regurgitation it is important to consider the interaction between chordal restraint and an altered mitral leaflet coaptation geometry.

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Omar, Alaa Mabrouk Salem, Mohamed Ahmed Abdel Rahman, Osama Rifaie, and Jonathan N. Bella. "Atrial Fibrillation in Heart Failure with Preserved Left Ventricular Systolic Function: Distinct Elevated Risk for Cardiovascular Outcomes in Women Compared to Men." Journal of Cardiovascular Development and Disease 9, no. 12 (November 26, 2022): 417. http://dx.doi.org/10.3390/jcdd9120417.

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Background: Heart failure with preserved ejection fraction (HFpEF) is prevalent in women and is associated with atrial fibrillation (AF). However, sex associations in AF-related HFpEF are not well explored. Aim: We studied differences between men and women with and without AF-related HFpEF symptoms on left ventricular (LV) geometry and diastolic dysfunction (DD) and their effect on cardiovascular events. Methods: Retrospectively, HFpEF patients with and without a history of AF referred for echocardiography were studied. Echocardiographic assessments were focused on LV geometry and diastolic functions. Patients were followed for the occurrence of cardiac events defined as death and cardiac hospitalization. Results: We studied 556 patients [age: 66.7 ± 17 years, 320 (58%) women, 91 (16%) AF]. Compared to HFpEF without AF (HFpEF-AF), HFpEF with AF patients (HFpEF+AF) were older (76 ± 13.8 vs. 64.9 ± 17.3 years, p < 0.001), had more risk factors, comorbidities, left ventricular hypertrophy (32 vs. 13%, p < 0.001), higher relative wall thickness (0.50 ± 0.14 vs. 0.44 ± 0.15, p < 0.001), and DD (56 vs. 30%, all p < 0.001). HFpEF+AF women had the worst clinical, LV geometric, and diastolic functional profiles and highest rates of cardiovascular outcomes compared to HFpEF+AF men and were the only group to predict outcomes (HR: 2.7, 95%CI: 1.4–5.1), while HFpEF-AF women were a low-risk group; HFpEF+AF and HFpEF-AF men had intermediate cardiovascular outcomes which were confirmed after propensity score matching. Conclusions: Among patients with HFpEF, women with AF had more abnormal LV geometry and diastolic function and had an increased risk of adverse cardiovascular outcomes independent of traditional risk factors, comorbidities, and baseline diastolic function.

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Roscani, Meliza Goi, Bertha Fulan Polegato, Suzana Erico Tanni Minamoto, Ana Paula Mena Lousada, Marcos Minicucci, Paula Azevedo, Luiz Shiguero Matsubara, and Beatriz Bojikian Matsubara. "Left ventricular sphericity index predicts systolic dysfunction in rats with experimental aortic regurgitation." Journal of Applied Physiology 116, no. 10 (May 15, 2014): 1259–62. http://dx.doi.org/10.1152/japplphysiol.00840.2013.

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Although an increased left ventricular (LV) diastolic diameter (DD) and a decreased ejection fraction have been used as markers for the surgical replacement of an insufficient aortic valve, these signals may be observed when irreversible myocardium damage has already occurred. The aim of this study was to determine whether change in LV geometry predicts systolic dysfunction in experimental aortic regurgitation. Male Wistar rats underwent surgical acute aorta regurgitation (aorta regurgitation group; n = 23) or a sham operation (sham group; n = 12). After the procedure, serial transthoracic echocardiograms were performed at 1, 4, 8, and 16 wk. At the end of protocol, the LV, lungs, and liver were dissected and weighed. During the follow-up, no animal developed overt heart failure. There was a correlation between the LV sphericity index and reduced fractional shortening ( P < 0.001) over time. A multiple regression model showed that the LVDD-sphericity index association at 8 wk was a better predictor of decreased fractional shortening at week 16 ( R2 = 0.50; P < 0.001) than was the LVDD alone ( R2 = 0.39; P = 0.001). LV geometry associated with increased LVDD improved the prediction of systolic dysfunction in experimental aortic regurgitation.

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Walker, Joseph C., Mark B. Ratcliffe, Peng Zhang, Arthur W. Wallace, Bahar Fata, Edward W. Hsu, David Saloner, and Julius M. Guccione. "MRI-based finite-element analysis of left ventricular aneurysm." American Journal of Physiology-Heart and Circulatory Physiology 289, no. 2 (August 2005): H692—H700. http://dx.doi.org/10.1152/ajpheart.01226.2004.

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Tagged MRI and finite-element (FE) analysis are valuable tools in analyzing cardiac mechanics. To determine systolic material parameters in three-dimensional stress-strain relationships, we used tagged MRI to validate FE models of left ventricular (LV) aneurysm. Five sheep underwent anteroapical myocardial infarction (25% of LV mass) and 22 wk later underwent tagged MRI. Asymmetric FE models of the LV were formed to in vivo geometry from MRI and included aneurysm material properties measured with biaxial stretching, LV pressure measurements, and myofiber helix angles measured with diffusion tensor MRI. Systolic material parameters were determined that enabled FE models to reproduce midwall, systolic myocardial strains from tagged MRI (630 ± 187 strain comparisons/animal). When contractile stress equal to 40% of the myofiber stress was added transverse to the muscle fiber, myocardial strain agreement improved by 27% between FE model predictions and experimental measurements (RMS error decreased from 0.074 ± 0.016 to 0.054 ± 0.011, P < 0.05). In infarct border zone (BZ), end-systolic midwall stress was elevated in both fiber (24.2 ± 2.7 to 29.9 ± 2.4 kPa, P < 0.01) and cross-fiber (5.5 ± 0.7 to 11.7 ± 1.3 kPa, P = 0.02) directions relative to noninfarct regions. Contrary to previous hypotheses but consistent with biaxial stretching experiments, active cross-fiber stress development is an integral part of LV systole; FE analysis with only uniaxial contracting stress is insufficient. Stress calculations from these validated models show 24% increase in fiber stress and 115% increase in cross-fiber stress at the BZ relative to remote regions, which may contribute to LV remodeling.

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Ye, Zi, Patricia A. Pellikka, and Iftikhar J. Kullo. "Sex differences in associations of cardio-ankle vascular index with left ventricular function and geometry." Vascular Medicine 22, no. 6 (September 20, 2017): 465–72. http://dx.doi.org/10.1177/1358863x17725810.

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The cardio-ankle vascular index (CAVI) is a measure of global arterial stiffness. We hypothesized that CAVI is associated with left ventricular (LV) function and geometry in individuals without structural heart disease. We measured CAVI in 600 participants (mean age 60.3±14.6 years, 54% men) without history of atherosclerotic cardiovascular disease who were referred for transthoracic echocardiography. Linear regression analysis was used to assess the association of CAVI with LV function (peak mitral annular systolic s’ and early diastolic velocity e’) and structure (LV mass index (LVMI) and relative wall thickness (RWT)). Older age, male sex, lower body mass index, history of hypertension, diabetes and chronic kidney disease were each associated with a higher CAVI (adjusted R2 = 0.56, all p < 0.01). A higher CAVI was associated with lower s’ and e’, and greater RWT, independent of age, sex, systolic BP and other conventional cardiovascular risk factors (all p < 0.05); a borderline association of higher CAVI with greater LVMI ( p = 0.05) was present. Associations with e’, s’ and RWT were similar in women and men but the association with LVMI was stronger in women than in men ( p for interaction = 0.02, multivariable-adjusted β = 6.92, p < 0.001 in women; p > 0.1 in men). In conclusion, a higher CAVI, a measure of global arterial stiffness, is associated with worse LV systolic function, worse diastolic relaxation, and greater LV RWT in both men and women, and with LVMI in women.

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Sanki, Bidyut, and Siddhartha Gadgil. "Graphs of systoles on hyperbolic surfaces." Journal of Topology and Analysis 11, no. 01 (February 27, 2019): 1–20. http://dx.doi.org/10.1142/s1793525319500018.

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Given a hyperbolic surface, the set of all closed geodesics whose length is minimal forms a graph on the surface, in fact a so-called fat graph, which we call the systolic graph. We study which fat graphs are systolic graphs for some surface (we call these admissible).There is a natural necessary condition on such graphs, which we call combinatorial admissibility. Our first main result is that this condition is also sufficient.It follows that a sub-graph of an admissible graph is admissible. Our second major result is that there are infinitely many minimal non-admissible fat graphs (in contrast, for instance, to the classical result that there are only two minimal non-planar graphs).

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Hashimoto, Ikuo, and Kazuhiro Watanabe. "Geometry-Related Right Ventricular Systolic Function Assessed by Longitudinal and Radial Right Ventricular Contractions." Echocardiography 33, no. 2 (January 27, 2016): 299–306. http://dx.doi.org/10.1111/echo.13039.

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Osorio-Yáñez, Citlalli, Julio C. Ayllon-Vergara, Laura Arreola-Mendoza, Guadalupe Aguilar-Madrid, Erika Hernández-Castellanos, Luz C. Sánchez-Peña, and Luz M. Del Razo. "Blood Pressure, Left Ventricular Geometry, and Systolic Function in Children Exposed to Inorganic Arsenic." Environmental Health Perspectives 123, no. 6 (June 2015): 629–35. http://dx.doi.org/10.1289/ehp.1307327.

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Picca, M., and F. Agozzino. "Abstract: P298 LEFT VENTRICULAR GEOMETRY AND FUNCTION IN ISOLATED SYSTOLIC HYPERTENSION: INFLUENCE OF GENDER." Atherosclerosis Supplements 10, no. 2 (June 2009): e606. http://dx.doi.org/10.1016/s1567-5688(09)70593-8.

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