Systolic and diastolic dyssynchrony are unaffected by revascularization of viable, dysfunctional myocardium.

Background: There is little information about change in dyssynchrony with stress or after revascularization.

Methods: Subjects were recruited to this study if they were referred for revascularization of viable, dysfunctional myocardium. The inclusion criteria were ejection fraction of < or = 35%, sinus rhythm, and QRS duration < or = 120 msec. Tissue Doppler echocardiography with dobutamine stress was performed at baseline and 6 months after revascularization, and dyssynchrony indices (T-sd(c)) were calculated.

Results: A total of 25 patients completed a 6-month follow-up. The mean (standard deviation) resting systolic and diastolic T-sd(c) at baseline were 49.3 (18.2) msec and 41.0 (29.4) msec, respectively, with little change during dobutamine stress. After revascularization, there were no significant differences in mean T-sd(c) although there was a modest effect on systolic T-sd(c) at recovery (46.0 [23.1] msec baseline, 34.2 [20.1] msec follow-up, mean difference 11.8 msec, 95% confidence interval 0.3-23.4 msec, P = .046).

Conclusion: Resting dyssynchrony in ischemic left ventricular dysfunction does not seem to be altered by dobutamine stress or revascularization.