The learning curve associated with transapical aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) has evolved to an accepted treatment option for high-risk elderly patients suffering from severe symptomatic aortic valve stenosis over the past few years. Recently, the first randomized trials demonstrated superiority of TAVI over medical treatment including balloon valvuloplasty (1) and non-inferiority compared to conventional aortic valve replacement (AVR) (2). TAVI prostheses can be implanted using the antegrade transapical (TA) approach or using a retrograde trans-vascular access (transfemoral TF, trans-subclavian TS, trans-aortic Tao). At present, there is no evidence proving the superiority of one or the other approach. Thus, the optimal access should be tailored to the individual patient profile. Given the truly minimally invasive nature of the TAVI technique, broadening of indications to patients with less risk profiles (moderate risk cohort) is tempting. However, several shortcomings of the current TAVI technique (occurrence of paravalvular leaks, relatively high pacemaker rates, unclear durability etc.) would have to be overcome first, especially in the context of the known excellent results of conventional AVR even in elderly patients (3). At present, the numbers of T-AVI procedures are rapidly increasing worldwide with several centers just about to start a new TAVI program. Thus, the learning curve in general associated with this new technique and specific major contributing factors are of particular interest.