Prevalence and Prognostic Relevance of Ventricular Conduction Disturbances in Patients With Aortic Stenosis

Abstract

The prevalence and prognostic implications of ventricular conduction disturbances in aortic stenosis (AS) have not been extensively evaluated. The present retrospective study investigated the prevalence and prognostic implications of ventricular conduction abnormalities (including the QRS morphology and duration) in AS. A total of 1,245 patients (mean age 66 ± 14 years, 62.8% men) with varying AS severity (aortic sclerosis 33.9%, mild AS 11.5%, moderate AS 29.9%, and severe AS 24.7%) were evaluated. Demographic, clinical variables, and presence of ventricular conduction abnormalities on the electrocardiogram (based on QRS morphology and duration) were related to occurrence of all-cause mortality, correcting for occurrence of aortic valve replacement. The prevalence of ventricular conduction disorders increased in parallel with AS severity, which was particularly significant for left bundle branch block (4.3% in aortic sclerosis, 2.1% in mild AS, 4.6% in moderate AS, and 8.1% in severe AS; p = 0.042). The QRS duration showed a slight prolongation with increasing AS severity (102 ± 21 ms in aortic valve sclerosis, 99 ± 18 ms in mild AS, 104 ± 22 ms in moderate AS, and 105 ± 22 ms in severe AS; p = 0.044). During a mean follow-up of 8.1 ± 4.8 years, 40.9% of patients died. Right bundle branch block morphology (hazard ratio 1.59, 95% confidence interval 1.18 to 2.13, p = 0.002) and increase of QRS duration (hazard ratio 1.06, 95% confidence interval 1.02 to 1.11; p = 0.006) were independently associated with all-cause mortality. In conclusion, ventricular conduction disorders became more prevalent with increasing severity of AS and have an impact on survival.