Left ventricular systolic synchrony and R-R interval in patients with coronary artery disease

Abstract

Assess the impact of R-R interval on LV systolic synchrony using simultaneous electrocardiographic (ECG) and real-time three dimensional echocardiography (RT3DE) in a defined population with coronary artery disease (CAD). 277 patients underwent coronary angiography (CAG), ECG and RT3DE. R-R internal was quantified by simultaneous ECG. Time to peak systolic longitudinal strain (Tssl) on 17 LV segment were quantified by four-dimensional (4D) speckle tracking echocardiography (STE) and manual measured. The R-R interval of 277 subjects ranged from 363.13 ms to 1425.00 ms, with a median of 849.49 ms (quartile range, 764.00–961.32 ms). Spearman correlation analyses indicated that R-R interval was positively associated with Tssl-Basal-A. With the independent predictors of R-R interval utilizing multiple regression analysis, Tssl -Apical-S (β=0.325, p=0.000), Smoking status (β=0.141, p=0.013), and Tssl-Basal-AL (β=0.151, p=0.014) were independently associated with the R-R interval. Univariate logistic regression for the presence of higher R-R internal (the median 849.49 ms was set the cutoff value) were indicated that the risk for the presence of higher R-R internal (odds ratio (OR), 1.009; 95% confidence interval (CI), 1.002-1.017, p=0.009). In multiple regression analyses, smoking status (OR, 1.943; 95% CI, 1.119-3.375, p=0.018), Tssl -Basal-AL (OR, 1.002; 95% CI, 1.000-1.004, p=0.043), Tssl -Mid-IS (OR, 1.008; 95% CI, 1.003-1.013, p=0.004), and Tssl -Apical-S (OR, 1.010; 95% CI, 1.004-1.016, p=0.002) remained independently associated with the risk of higher R-R internal in the population. Tssl on 17 LV segment are associated with the relationship between R-R interval and left ventricular systolic synchrony.