Evaluation of systolic time intervals in patients of ischemic heart disease with clinical heart failure

Abstract

Introduction: Left ventricular (LV) systolic function evaluation is based on ejection fraction assessment. Due to the great sensitivity of the examination and the ease of measurement, systolic time intervals (STIs) are ideally appropriate for studying the effects of pharmacologic agents upon the heart. In this context, the present study aimed to estimate and compare STI in patients with ischemic heart disease (IHD) with clinical heart failure and among control subjects without clinically established LV dysfunction based on their LV ejection fraction (LVEF). Materials and Methods: This case–control study included 33 IHD patients as cases and 32 healthy subjects as controls. All subjects underwent pulsed-Doppler echocardiogram to estimate STIs: total electromechanical systole (QS2), preejection period (PEP), and LV ejection time (LVET). Results: A significant difference between PEP (145.23 ± 23.20 vs. 82.99 ± 8.63, P < 0.00001), LVET (231.34 ± 40.89 vs. 265.39 ± 31.98, P = 0.000947), and PEP/LVET ratio (0.63 ± 0.15 vs. 0.31 ± 0.08, P < 0.00001) between cases and controls was found. On subgroup analysis, a weak correlation was found in patients with LVEF ≤40% and PEP/LVET (r = −0.3677, P = 0.1958). In addition, a relatively strong correlation between LVET and heart rate (r = −0.432, P = 0.012) was found among the cases. Conclusion: The current study results showed that the differences in the values of STI among cases than in controls could be an indicator of LV systolic dysfunction. In addition, this method may have impending applications in the management of IHD.

Keywords

• echocardiography
• ischemic heart disease
• left ventricular function
• myocardial infarction
• systolic time intervals