Study Population
A total of 236 patients (59 BAV and 177 TAV) were selected from our health system-wide database of 60,383 echocardiography reports from 2013-2018. These included echocardiograms obtained for any indication at 32 sites encompassing 5 tertiary-care hospitals and over 120 clinics at satellite locations throughout the state. For the BAV cohort, the database was queried for all mentions of “bicuspid aortic valve” or “BAV”. Initially, 222 patients with BAV confirmed by echocardiography were identified. We then reviewed the records of these patients and included patients with an initial diagnosis of mild or moderate AS and echocardiographic follow-up greater than or equal to 6 months from initial diagnosis of AS. Patients were excluded if they never progressed beyond “trace” severity or if they had an initial severity of “severe”. Other exclusion criteria were active atrial fibrillation, active endocarditis, and history of aortic valve or aortic surgery prior to the initial echocardiogram. Ultimately, 59 patients with BAV were included in this study.
To identify our TAV cohort, we randomly sampled from our echo database for reports of mild and moderate AS in proportions identical to that of the initial BAV cohort. For each patient selected, we reviewed the medical record and enrolled them based on the criteria described above. Sampling continued until the cohort consisted of 177 TAV patients, stratified by mild or moderate initial severity in a 3:1 TAV-to-BAV ratio.
This study was approved by the Yale Institutional Review Board and written informed consent was waived.