Management of Coronary Artery Disease and Conduction Abnormalities in Transcatheter Aortic Valve Implantation.

Transcatheter aortic valve replacement (TAVR) is an expanding, catheter-based technology that allows the implantation of a prosthetic valve without requiring open heart surgery for the treatment of severe aortic stenosis (AS). The frequency of coronary artery disease (CAD) in patients (pts) with severe AS undergoing surgical treatment ranges from 30 to 50 %. This tends to be higher in pts undergoing TAVR with a prevalence of 49-76 % and is more prevalent with older age and the fact that TAVR is commonly performed in high-risk groups with more advanced cardiovascular disease. The overall influence of CAD on TAVR procedural outcomes remains controversial, and the management of concomitant artery disease is still under discussion. There are three major issues that must be addressed: the impact of CAD, optimal timing of percutaneous coronary intervention (PCI) and TAVR, and extent of revascularization. Today, TAVR is commonly performed as a stand-alone procedure with variable degrees of concomitant CAD tolerated without intervention. One of the major potential complications with TAVR is the damage to the conduction system. The requirement of permanent pacemaker (PM) implantation ranges from 9 to 49 % of cases with a mean of ~20 %, whereas surgical aortic valve replacement (sAVR) is associated with a complete heart block that requires permanent PM in 3-12 % of cases. Reports have demonstrated an increased incidence of conduction damage in patients undergoing TAVR with the CoreValve (Medtronic Minneapolis, MN, USA) prosthesis (mean 20.8 %, range 9.3-30.0 %) compared with the Edwards SAPIEN (Edwards Lifesciences LLC; Irvine, CA, USA) prosthesis (mean 5.4 %, range 0-10.1 %). Factors predicting PM implantation include preexisting bundle branch block (BB) or conduction abnormalities. The prognostic significance of new left bundle branch block (LBBB) after TAVR is unclear. In the future, new valve designs may improve the incidence of permanent PM implantation after TAVR.