Comparison of Frequency of Ischemic Cardiovascular Events in Patients With Aortic Stenosis With Versus Without Asymmetric Septal Hypertrophy (from the SEAS Trial)

Abstract

Asymmetric interventricular septum hypertrophy (ASH) has been associated with increased perioperative morbidity and mortality in patients with severe, symptomatic aortic valve stenosis (AS). Less is known about the prognostic impact of ASH during progression of AS. Clinical, echocardiographic, and outcome data from 1,691 patients with initially asymptomatic, mostly moderate AS, participating in the Simvastatin Ezetimibe in Aortic Stenosis (SEAS) study was used. ASH was considered present if interventricular septum/posterior wall thickness ratio in end-diastole ≥1.5. The associations of ASH with hazard rate of ischemic cardiovascular events were tested in time-dependent Cox regression analyses. Based on the presence of ASH at study echocardiograms, the study population was grouped in to a no-ASH, nonpersistent ASH, persistent ASH, and new-onset ASH groups. During a median of 4.3years of follow-up, ASH persisted or developed in 17% of patients. Persistent or new-onset ASH was characterized by higher left ventricular mass index and ejection fraction at baseline (both p <0.05) but not with female gender or hypertension. In time-varying Cox regression analyses adjusting for these confounders, persistent or new-onset ASH was associated with higher hazard rate of ischemic cardiovascular events (hazard rate 1.45; 95% confidence interval 1.09 to 1.91, p= 0.01), in particular coronary artery bypass grafting (hazard rate 1.69; 95% confidence interval 1.17 to 2.47; p= 0.006), whereas no association with increased mortality was found. In conclusion, in patients with AS without diabetes or known renal or cardiovascular disease participating in the SEAS study, persistent or new-onset ASH during progression of AS was associated with higher rate of ischemic cardiovascular events.