Morphological characteristics of severe aortic stenosis in China: imaging corelab observations from the first Chinese transcatheter aortic valve trial.

OBJECTIVES

We sought to describe the morphological characteristics of aortic valve disease in a Chinese population presenting for transcatheter aortic valve replacement (TAVR).

BACKGROUND

Racial and regional differences are known to exist in aortic stenosis (AS), but limited data exist comparing the specific anatomical variations between populations.

METHODS

Patients were prospectively evaluated in a Chinese population presenting for TAVR in the Venus A-Valve trial, the first trial evaluating TAVR in China. A systematic anatomical assessment protocol employed contrast-enhanced computed tomography (CT) in all the cases.

RESULTS

A total of 120 consecutive patients were studied. Of these, 61 (50.7%) were patients with tricuspid, 57 (47.5%) bicuspid, and 2 (1.7%) unicuspid valve morphologies. Of the 57 cases with bicuspid valve, 31 (54.4%) had no raphe (Sievers classification, type 0) and 26 (45.6%) were of raphe type. Although the incidence of bicuspid valve morphology was more than a third in the northern Chinese population, this was lower than the eastern Chinese population (P = 0.035), in whom the incidence was more than half. A comparison of tricuspid morphologies in China versus a Western series of 229 consecutive patients undergoing TAVR assessed with CT showed a threefold excess of leaflet calcium burden in China, with a leaflet calcium volume of 421 mm(3) (IQR, 188-688 mm(3) ) versus 142 mm(3) (IQR, 58-267 mm(3) ).

CONCLUSIONS

Patients presenting for TAVR in China have a very high frequency of bicuspid valve morphology. Even in tricuspid disease, there are clear differences to Western patients, with a high calcium burden, which presents challenges for TAVR in this population (ClinicalTrials.gov NCT01683474).