Abstract 19209: Wide Qrs and Rbbb Morphology Are Associated With Worse Prognosis in Aortic Stenosis

Background: The prevalence and prognostic importance of QRS morphology and duration have not been previously documented in a population comprising all grades of aortic stenosis (AS) patients. Purpose: To evaluate the prevalence of left (LBBB), right bundle branch block (RBBB) and interventricular conduction delay (IVCD) across various grades of AS, and to investigate the prognostic implications of QRS morphology and duration. Methods: A total of 1245 patients (mean age 66 ± 14 years, 62.8% men) with various grades of AS (aortic sclerosis 33.9%, mild AS 11.5%, moderate AS 29.9%, severe AS 24.7%) were evaluated. Demographic, clinical and ECG characteristics (QRS morphology and duration) were collected and related to the occurrence of all-cause mortality at follow-up. In a Cox regression analysis, subsequent aortic valve replacement was included as a time dependent co-variate. Results: During a mean follow-up of 8.1±4.8 years, 42.7% of the patients underwent aortic valve replacement and 41% died. LBBB morphology became more prevalent with increasing AS severity (p = 0.042). On top of a model with known risk factors in aortic stenosis (baseline model χ2 = 54.7), both RBBB morphology (HR 1.59; 95% CI 1.18-2.13, p = 0.002) and QRS prolongation per 10 ms (HR 1.06, 95% CI 1.02-1.11; p = 0.006) independently increased the risk of all-cause mortality. QRS morphology (model χ2 = 65.2, p = 0.027) and QRS duration (model χ2 = 63.7, p = 0.007) were both independent and equivalent predictors of all-cause mortality. (Table) Conclusions: With worsening severity of AS, there was a significant increase in prevalence of LBBB morphology. Longer QRS duration and RBBB morphology were independently associated with worse prognosis.