Left ventricular flow vector characteristics and the relationship between flow vector and left ventricular systolic function in patients with anterior myocardial infarction / 中华心血管病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To assess left ventricular vortex and flow vector features and the relationship between vector flow and left ventricular systolic function in patients with anterior myocardial infarction by echocardiography-derived vector flow mapping (VFM).</p><p><b>METHODS</b>Echocardiography was performed in 31 patients with anterior myocardial infarction and 20 healthy controls. Flow vector and velocity of left ventricle were analyzed on apical 3 chambers view with color Doppler.</p><p><b>RESULTS</b>(1) Left ventricular intracavitary vortex during isovolumic contraction phase could be detected in both groups. Vortex was detectable also during contraction phase and relaxation phase in patients with myocardial infarction. There was no vortex during contraction phase, and there was only small and transit vortex during relaxation phase in control group. (2)Flow vector of apex and middle segments directed to apex and was opposite to that of basal segment of left ventricle in patients with myocardial infarction and in controls [(10.6 ± 8.3) cm/s vs. -(5.8 ± 7.2) cm/s, (19.5 ± 11.8) cm/s vs. -(16.6 ± 14.7) cm/s]. During rapid relaxation phase, the velocity in apex was lower in patients with myocardial infarction than that in control group [(6.8 ± 9.8) cm/s vs. (17.6 ± 15.8) cm/s, P < 0.01]. (3) There was a negative correlation between velocity in apex and left ventricular ejection fraction (LVEF) during rapid eject phase in patients with anterior myocardial infarction (r = -0.52, P < 0.05). Velocity in apex of patients with LVEF < 50% was higher than that of patients with LVEF ≥ 50% during rapid eject phase [(13.5 ± 9.0) cm/s vs. (5.8 ± 5.1) cm/s, P < 0.05].</p><p><b>CONCLUSIONS</b>Vortex period is prolonged in patients with anterior myocardial infarction compared to normal controls during whole cardiac cycle, flow vector of apex and middle segments is directed to apex during eject phase and there is a negative correlation between velocity in apex and LVEF during rapid eject phase in patients with anterior myocardial infarction.</p>