Assessment of intraventricular systolic asynchrony in patients with atrial fibrillation using triplane tissue Doppler imaging.

Abstract

BACKGROUND: Triplane tissue Doppler imaging (TDI) makes it possible to simultaneously obtain three apical view images and to measure the dyssynchrony index (DS) for 12 segments in patients with atrial fibrillation (AF). We evaluated the feasibility of using triplane TDI to assess intraventricular asynchrony in AF.

METHODS: In 50 patients with AF, triplane TDI was used for the analysis of myocardial velocity curves of 12 (six basal and six mid) left ventricular (LV) segments by apical two-, three-, and four-chamber views. Time to peak systolic velocity (Ts) was measured, and DS was calculated as the standard deviation (SD) of Ts over 12 segments. The DS(avg) was defined as the average of DS of eight consecutive cycles. To assess the cyclic variability of DS, the coefficient of variation of DS (CoV(DS)) was calculated as the SD of DS for eight cycles divided by DS(avg) [SD(DS)/DS(avg)]. CoV(RR), representing the variability of RR intervals, was defined as [SD(RR)/RR(avg)]. Patients with a left ventricular ejection fraction (LVEF) of 45% or more were classified as group A, and patients with an LVEF less than 45% as were classified as group B.

RESULTS: The mean LVEF was 47% +/- 12%. Group B showed larger LV volume and lower sphericity index compared with group A. Intraobserver and interobserver variability of DS(avg) were 6% and 9%, respectively. More severe dyssynchrony was observed in group B (DS(avg); 23.5 +/- 8.5 ms in group B vs. 17.7 +/- 6.1 ms in group A, P = .008). DS(avg) was not related to RR(avg) or CoV(RR). DS(avg) negatively correlated with ejection fraction (r = -0.404, P = .004) and sphericity index (r = -0.317, P = .025) and showed positive correlation with LV volume.

CONCLUSION: Analysis of asynchrony by triplane TDI was feasible in patients with AF. DS(avg) correlated with echocardiographic parameters of systolic function.