Aims: We sought to determine whether inter- or intra-ventricular systolic dyssynchrony contributes to the occurrence of elevated pulmonary artery systolic pressure (PASP) in patients with coronary artery disease (CAD).
Methods and results: One hundred and fifty-three consecutive CAD patients with preserved left ventricular ejection fraction (LVEF >40%) were enrolled. Detailed echocardiography was performed to measure PASP, inter-ventricular dyssynchrony (Ts-RL: time difference between lateral and right free wall), and intra-ventricular dyssynchrony (Ts-SD, standard deviation of time to peak systolic velocity of 12 LV segments; Ts-12, maximal difference in Ts between any 2 of 12 LV segments; Ts-6-basal, maximal difference in Ts between any 2 of 6 basal LV segments). Elevated PASP (>35 mmHg) was confirmed in 46 patients who had significantly prolonged intra-ventricular dyssynchrony (Ts-SD: 49.9 ± 19.6 vs.37.9 ± 19.8 ms; Ts-12: 147.9 ± 56.4 vs.110.9 ± 53.9 ms; Ts-6-basal: 114.2 ± 51.9 vs. 85.7 ± 48.5 ms, all P < 0.01) and inter-ventricular dyssynchrony (Ts-RL: 78.7 ± 46.4 vs. 62.7 ± 34.3 ms, P = 0.019) compared with those without elevated PASP. Indexes of intra- and inter-ventricular dyssynchrony and LV filling pressure (E/e') were significantly correlated with PASP. Multivariate analysis showed that left atrial dimension [odds ratio (OR) 4.23, 95% confidence interval (CI) 1.64-10.90], E/e' septal (OR 1.15, 95% CI 1.04-1.27), pulmonary vascular resistance (OR 5.38, 95% CI 1.55-18.74), and Ts-RL (OR 1.02, 95% CI 1.01-1.03) were independent predictors for the occurrence of elevated PASP (all P < 0.05).
Conclusion: Elevated PASP is common in CAD patients with preserved LVEF and is associated with LV diastolic dysfunction and LV mechanical dyssynchrony.