Quantitative Assessment of Left Ventricular Systolic Function in Patients with Coronary Heart Disease by Velocity Vector Imaging

OBJECTIVE: To assess the left ventricular (LV) longitudinal systolic function and asynchrony in patients with coronary atherosclerotic heart disease (CAD) by syngo velocity vector imaging (VVI). METHODS: Twenty-eight control subjects and 79 patients with CAD were examined, including 28 patients with myocardial infarction, 26 patients with coronary lumen stenosis <50%, and 25 patients with myocardial ischemia. According to the results of coronary arteriography and electrocardiogram (ECG), the myocardial segments of the LV of CAD patients were divided into four groups: ischemic, infarcted, nonischemic, and normal. Dynamic imaging was performed on all subjects. The systolic peak strain (Smax), systolic strain rate (SRmax), time to peak strain (PTs), and time to peak strain rate (PTsr) in every cardiac cycle were measured. RESULTS: A total of 1,253 out of 1,712 (96.5%) segments were successfully analyzed with VVI. Smax and SRmax of the ischemic and infarcted segments were impaired in CAD patients. Optimal sensitivity and specificity were obtained with strain and strain rate cutoffs of -14.08% and -0.83 s(-1) , respectively, for detecting ischemic segments and -6.65% and -0.38 s(-1) , respectively, for detecting infarcted segments. The PTs and PTsr were significantly longer in the ischemic and infarcted segments compared to those of the control group. CONCLUSIONS: Utilizing VVI, the longitudinal strain, strain rate, and peak time in CAD patients are easy to obtain and reproducible. Strain and strain rate cutoff values of abnormal myocardium are valuable for detecting ischemia and infarction. The PTs and PTsr values possibly estimate myocardium asynchrony in CAD patients.