The prevalence of severe aortic stenosis (AS) in the elderly is substantial with an estimation of 290,000 transcatheter aortic valve replacement (TAVR) candidates under the current indications, according to a study published May 28 in the Journal of the American College of Cardiology.

The study, a systematic review and meta-analyses of seven population-based studies with 9,723 patients ages 75 and older, found that the pooled prevalence of all AS was 12.4 percent (95 percent CI, 6.6 percent - 18.2 percent), while the pooled prevalence of severe AS was 3.4 percent (95 percent CI, 1.1 percent - 5.7 percent).

Further, among severe AS patients, 75.6 percent (95 percent CI, 65.8 percent – 85.4 percent) were symptomatic, and 40.5 percent (95 percent CI, 35.8 percent – 45.1 percent) of these patients were not treated surgically. From those, 40.3 percent (95 percent CI, 33.8 percent – 46.7 percent) received TAVR.

The authors projected that that there are approximately 189,836 (95 percent CI, 80,281-347,372) TAVR candidates in Europe, and 102,558 (95 percent CI, 43,612-187,002) TAVR candidates in North America. Further, each year there are about 27,000 new TAVR candidates: 17,712 in Europe and 9,189 in North America.

Moving forward, the authors conclude that "these estimates have considerable clinical, economic, and social implications," however, "additional population-based studies that use a unified echocardiographic definition of AS are warranted."

In a related editorial comment, Alec Vahanian, MD, Bernard Iung, MD, and Dominique Himbert, with the Cardiology Department, Bichat Hospital, University ParisVII, in Paris, France, note that, "it is difficult to precisely evaluate the number of 'TAVI candidates' from meta-analysis because the decision for TAVI requires a carful individual evaluation of each patient in this population by a Heart Team." They add that the study "is an important contribution, however as TAVI moves forward we need actual figures and must perform contemporary prospective observational studies in order to accurately assess the number of possible candidates to TAVI."

Keywords: Prevalence, North America, Europe, United States, Echocardiography