Trends in aortic valve surgery in a large multi-surgeon, multi-hospital practice, 1979-1999.

Background And Aim Of The Study: Trends in aortic valve operations (AVO) may help to predict the future of aortic valve surgery in the context of changing case mix, population demographics, emerging technology and shifting paradigms.

Methods: All adults undergoing single AVO between 1979 and 1999 were reviewed retrospectively according to age, gender and other typical clinical variables, surgical complexity, specific operation and immediate outcome.

Results: There were 3,917 single AVO. Although coronary artery bypass (CAB) volumes declined by 15.3% between 1996 and 1999, AVO volumes have continued to increase by 11.7% since 1996. Over the entire period, there was no significant change in mean age or percent female gender, but increases in the prevalence of octogenarians and aortic stenosis were noted. During the 1990s, degenerative valve disease predominated and the prevalence of sicker patients according to heart failure class and surgical priority decreased. Trends in surgical complexity included an increase in AVO combined with CAB, but a stable 9:1 distribution of first operations to reoperations. Technology adoption included a decreased prevalence of mechanical valve use at the expense of increased use of tissue valves, especially stented xenografts and homografts. Transient technology adoption included stentless xenografts. Small numbers of pulmonary autografts, aortic valve repairs and valve-sparing aortic replacements were carried out. Predictors of hospital mortality rates for AVO included age 65 years, reoperation and combined AVO. Hospital mortality rates for AVO decreased for most age groups between the 1980s and 1990s, but not during the 1990s.

Conclusion: AVO volumes are steadily increasing, apparently as a result of the increase in octogenarians and the start of the 'baby boom' wave. Hospital mortality risk is related to age and surgical complexity, but is modest and has stabilized during the past decade. The prevalence of mechanical valve implants has decreased in favor of tissue valve replacement categories. The fastest growth rates have been with stented xenografts, and especially homografts. This may represent a paradigm shift away from mechanical solutions in favor of tissue solutions for aortic valve disease.