Aortic valve calcium scoring is a predictor of paravalvular aortic regurgitation after transcatheter aortic valve implantation.

Abstract

Degenerative aortic stenosis is the most common native valve disorder in the ageing population of industrialized nations. Surgical aortic valve replacement has excellent clinical outcomes but there is an increasing number of patients with severe aortic stenosis who are not considered surgical candidates because of significant co-morbidity. Transcatheter aortic valve implantation (TAVI) has been established as a clinically accepted minimally invasive therapeutic option for selected high-risk patients with symptomatic aortic valve stenosis (1-4). The Edwards SAPIEN™ prosthesis (Edwards Lifescience, Irvine, USA) which can be deployed via both transfemoral and transapical routes, and the CoreValve Revalving System® (CoreValve Inc., Irvine, California) which is inserted only via a transfemoral approach, represent the currently used transcatheter aortic valves. The technical feasibility has been shown for both approaches (5,6) and when successful, transcatheter aortic valve replacement results in marked hemodynamic and clinical improvements (7,8). However, despite a clear benefit of survival and improvement in symptoms (1,2), TAVI is also associated with post-implantation paravavular aortic regurgitation (PAR) in up to 60% of patients (3). In contrast with surgery, TAVI does not involve excision of the diseased native valve. The metal stent of the implanted device leads to compression of native valve cusps and associated calcification against the aortic annulus and aortic wall. The precise mechanism behind this phenomenon remains unclear. PAR may be related to the specific anatomy of the annulus and aortic root, as well as to the amount and distribution of leaflet and annular calcification (9). Although efforts have been made to reduce this incidence significantly (10,11), PAR still necessitates additional interventions in a considerable number of patients and its presence is known to confer a higher mortality rate amongst patients undergoing TAVI procedures (12). This has led to guarded acceptance of TAVI in patients others than those in high-risk or inoperable patient populations. Therefore, careful patient selection is of fundamental importance to avoid intraoperative complications. Excessive calcification of the aortic valve cusps may result in haemodynamically relevant PAR (10), further sustaining pressure overload, which is poorly tolerated by these patients. As a result, several imaging methods have been routinely used for procedure planning and proper device selection (9,13-20). The size of the aortic annulus is commonly assessed by transoesophageal echocardiography (TEE) (9), and multidetector row computed tomography (MDCT) (14,15). MDCT has increased its role because it not only enables the evaluation of the distances from the annulus to the coronary ostia, but also allows accurate detection, localization and quantification of aortic valve calcification and calcification of the entire aorta (14-22). It has been demonstrated that the amount of aortic valve calcium is associated with unfavorable prognosis (23). Recent studies using MDCT have focused on the role of aortic valve calcium (AVC) and its relation to post TAVI AR (17-22). We are providing a video presentation entitled “Aortic valve calcium scoring is a predictor of paravalvular aortic regurgitation after transcatheter aortic valve implantation” (Video 1). Open in a separate window Video 1 Aortic valve calcium scoring is a predictor of paravalvular aortic regurgitation after transcatheter aortic valve implantation