Outcome of aortic valve replacement in aortic stenosis : the number of valve cusps matters

Although the prevalence of bicuspid aortic valve (BAV) is only 0.5–1% in children, it accounts for about half of aortic valve replacements (AVRs) for aortic valve stenosis (AS). These findings illustrate that valve remodelling occurs more frequently and more rapidly on bicuspid than on tricuspid aortic valves (TAVs). During their lifetime, most subjects with a BAV develop aortic valve dysfunction, mostly AS, whereas only 1% remains with a normal valve function.1 In both subjects with a BAV and those with a TAV, age is a powerful risk factor for AS, and the prevalence of this disease in the population is 3% and 10%, in the subjects >65 and 80 years of age, respectively.2 Individuals with a BAV, however, develop AS one or two decades earlier than those with a TAV and their lifetime risk of AVR is around 50% (Table 1). In this issue of the journal, Huntley et al.3 present an elegant study in which they compared age-matched cohorts of 198 BAV stenosis and 198 TAV stenosis patients. The authors found that, at a given age, patients with TAV stenosis have higher prevalence of cardiovascular risk factors, greater degree of cardiac impairment and worse survival after AVR compared to those with BAV stenosis