The surgeon’s role in transcatheter aortic valve implantation (TAVI)

Transcatheter aortic valve implantation (TAVI) has evolved into a routine procedure for elderly high-risk patients with severe aortic stenosis in specialised centres. It can be performed via a transfemoral or a transapical approach. Both approaches are truly minimally invasive and avoid the use of cardio-pulmonary bypass and cardioplegic arrest. TAVI is associated with good outcome and acceptable complication rates. The outcome of TAVI has improved over the last few years as centres became more experienced in the procedure. Up to now there is no clear evidence-based benefit for one or the other approach. A careful patient selection for each approach is therefore crucial for good results. Both procedures should be performed by a heart team of cardiologists, cardiac surgeons and cardiac anaesthetists.The knowledge the cardiac surgeons gained over the last decades by treating aortic stenosis with conventional aortic valve replacement is very important in TAVI procedures: Not only in terms of the procedure itself, but also for preoperative patient screening. TAVI must be approached as a team effort where cardiologists and cardiac surgeons play an equal role and should not be performed without a cardiac surgeon

Minimally invasive off-pump valve-in-a-ring implantation: the atrial transcatheter approach for re-operative mitral valve replacement after failed repair

OBJECTIVE: Based upon recent developments in transcatheter technology, this study was designed to evaluate the feasibility and haemodynamic performance of transcatheter valve-in-a-ring (VinR) implantation for potentially failed mitral repair using a minimally invasive, transatrial, off-pump approach. METHODS: Adult sheep (54.3+/-3.0 kg) underwent mitral valve repair with a 26 mm complete annuloplasty ring (Physio) using standard conventional techniques. To simulate the redo operation, a transcatheter 23 mm pericardial prosthesis (Edwards Sapien) mounted on a balloon-inflatable steel stent was deployed within the annuloplasty ring. VinR implantation was performed off-pump under rapid pacing in four and on-pump in three animals using an antegrade transatrial approach under fluoroscopic guidance. RESULTS: Transcatheter VinR implantation was successful in all seven sheep. Mean transvalvular gradient was 4.9+/-0.3 mmHg. VinR function was excellent with no leak in one, good with mild leak in five (trans-stent: four, paravalvular: one) and sufficient with moderate central leak in one animal, respectively. Valve deployment required 10.0+/-0.7 min and all transcatheter prostheses were confirmed in good position on postmortem analysis, without any signs of valve dislocation or embolisation. In an in-vitro model, the minimum force required to dislodge the valve was 32.9+/-5.2N, which was well above the normal estimated forces generated by the left ventricle. One animal was kept alive to assess mid-term outcome and is still well 12 months after the VinR implantation. CONCLUSIONS: Transatrial, transcatheter mitral VinR implantation is feasible using a minimally invasive off-pump approach. VinR implantation is a promising concept for re-operative surgery for selected patients after failed mitral valve repair