Bicuspid aortic valves – increased morbidity but not mortality

Bicuspid aortic valve is the commonest congenital cardiac abnormality in the adult population.  Previous pathological studies have outlined aortic valve dysfunction, endocarditis, and even aortic dissection as potential causes of increased morbidity in this patient group.  The purpose of this study was to observe the disease progression and cardiac outcomes of a large contemporary adult cohort of patients with bicuspid aortic valves.

642 adults (mean age 35 years; 68% male) were followed up for a mean of 9 years.  The main outcome measure was the occurrence of: cardiac death, intervention on the aortic valve or ascending aorta, aortic dissection or aneurysm, or congestive heart failure requiring hospital admission during the follow-up period.  During the follow-up period there were 28 deaths (mean 4%).  One or more primary cardiac events occurred in 161 patients (mean 25%), including cardiac death in 17 (mean 3%), intervention on the aortic valve or ascending aorta in 142 patients (mean 22%), aortic dissection or aneurysm in 11 (mean 2%) or congestive heart failure in 16 patients (mean 2%).  Independent predictors of primary cardiac events were age older than 30 years (Hazard Ratio, 3.01), moderate or severe aortic stenosis (HR, 5.67), and moderate or severe aortic regurgitation (HR, 2.68).  At 10 years, survival in the group studied (mean 96%) was not significantly different from population estimates (mean 97%; p=0.71).

Although the mortality rates in this study are reassuring, it was noted that patients with valvular regurgitation or stenosis, or those over 30, were more likely to require intervention, and as such represent a group that require closer monitoring.  In this regard, MRI should play a complementary role to echocardiography in monitoring the aortic root, which also needed replacement in 29% of patients who underwent aortic valve replacement.

  • Tzemos N, Therrien J, Yip J, et al. Outcomes in adults with bicuspid aortic valves. JAMA 2008; 300:1317-1325.