Introduction
Aortic stenosis (AS) is a common cause of valvular heart disease worldwide. Its prevalence increases with age, ranging from 4.6%-6.4% in U.S. adults aged 75 years and older.1, 2 The most common etiology of aortic stenosis is degenerative calcification, which is primarily associated with aging as well as other cardiovascular disease. However, the presence of bicuspid aortic valve (BAV) represents a major risk factor in the development of AS in younger populations and is present in 65% of adults aged 60 and younger undergoing aortic valve replacement for aortic stenosis.3 While patients with BAV are known to develop AS more frequently and earlier than patients with tricuspid aortic valve (TAV), it remains uncertain whether BAV is associated with faster progression of AS severity once AS develops, which is important to guide screening and intervention practices.4
While the progression rate of AS varies widely among individuals, older age, male sex, coronary artery disease, plasma levels of oxidized phospholipids, and baseline hemodynamic severity have all been associated with more rapid progression.5-8 BAV has been implicated in certain studies,9, 10 but others have shown no difference in AS progression rate between BAV and TAV phenotypes.5, 11 Furthermore, these findings were drawn from post hoc analyses of clinical trials aimed at determining effects of metabolic syndrome and plasma lipids on AS disease progression. As a result, these studies examined very small cohorts of BAV patients (N<41), representing a significant limitation in the current literature. These findings attest to the need for more investigations to better understand progression of more-than-mild AS in BAV patients.
Using a healthcare system-wide echocardiographic database, we aim to determine the hemodynamic progression rate of mild and moderate severe aortic stenosis in patients with BAV as compared to patients with TAV.