Adverse effects of left ventricular electrical dyssynchrony on cardiac reverse remodeling and prognosis after aortic valve surgery.

BACKGROUND

Electrical dyssynchrony (ED) is one of the important contributing mechanisms in the progression of heart failure. We hypothesized that ED would interfere with cardiac reverse remodeling and affect prognosis after aortic valve surgery.

METHODS

A total of 411 consecutive patients (233 males, mean age 65±11 years) who underwent aortic valve surgery were retrospectively analyzed. The patients were divided into two groups according to the presence of ED [Group 1: no ED (n=382, 93%), Group 2: ED (n=29, 7%)]. ED was defined as either left ventricular bundle branch block, or electrical pacing rhythm. Cardiac reverse remodeling was assessed at 1 year after surgery by the changes in left ventricular ejection fraction (LVEF), LV end-systolic volume (LVESV), and left atrial volume index (LAVI). The primary endpoint was a composite of hospitalization for heart failure, and all-cause mortality.

RESULTS

At 1 year after surgery, group 2 showed lower LVEF (58±15% vs. 64±9%, p=0.044), and higher LAVI (42±18ml/m2 vs. 33±13ml/m2, p=0.018) than group 1. However, LVESV values (55±38ml vs. 42±24ml, p=0.076) were not significantly different. In particular, in patients with reduced preoperative LVEF, the LVEF was markedly increased in group 1 but not in group 2 after 1 year. During a median follow-up of 39 months, group 2 showed a worse clinical outcome than group 1 (20.7% vs. 7.6%, p=0.031). After adjusting for confounding factors in the multivariate analyses, age [hazard ratio (HR) 1.11, 95% confidence interval (CI) 1.06-1.16, p<0.001] and the presence of ED (HR 2.43, 95% CI 1.01-5.89, p=0.046) were found to be independent predictors of clinical outcomes.

CONCLUSIONS

ED after aortic valve surgery negatively affected cardiac remodeling and prognosis.