Calcium deposits, fibrosis and advanced age are risk factors common to severe aortic stenosis and AF. Not surprisingly, about a third of all patients undergoing TAVI have pre-existing AF.10,11 An additional 5-10% may have pre-existing, but undetected AF. Previous studies have reported new-onset AF after transcatheter aortic valve replacement (TAVR) in about 7-8% of patients,12,13 similar to the 11% reported in the study by Manuel et al. Changes in volume state, systemic inflammatory response and non-transfemoral access may all act as a trigger of new onset atrial fibrillation.10 Studies have consistently demonstrated an increased stroke risk in such patients. Indeed, new onset AF after TAVI has been linked to an absolute stroke increment as high as 3% and to increased mortality.12 Early diagnosis and proper treatment of new onset AF is of importance, however scientific evidence guiding optimal anticoagulation management in TAVI patients is scarce. Direct oral anticoagulants appear to be safe and effective in patients with bioprosthetic valves, but not in patients with mechanical prostheses.14 Moreover, data from our group suggest that continuation of oral anticoagulation may be equally safe and efficacious as the interruption of anticoagulation in patients with pre-existing AF undergoing TAVI.11

During TAVR, there is a direct interaction beetween the conduction system and the stiff wire, the balloon, the delivery catheter and the transcatheter heart valve itself. New LBBB is most frequently observed and thus, patients with a pre-existing right bundle branch block are at high risk for the development of an intra- or postprocedural high-grade AV block. Identification of new LBBB is important as it may progress further to a delayed high-grade AVblock. Also, studies have consistently associated new LBBB with an increased risk for sudden cardiac death, reduced left ventricular ejection fraction and heart failure, especially in patients with a long QRS duration.2–4 Choice of prosthesis, depth of implantation and the degree of oversizing are the main predictors of new LBBB. Indeed the risk of a new LBBB shows a relative increase of ∼20-30% per 1 mm of implantation depth.2 To achieve a high implantation with self-expanding valves, the cusp-overlap technique has become popular.15 With this technique (often a right anterior oblique/caudal projection), the right and the left coronary cusps are overlapped and the non-coronary cusp is used as a reference for implantation depth. This technique enables a high implantation and at the same time mitigates the risk of device pop-out.

In recent years, physicians have attempted to simplify and streamline the procedure and early discharge has been advocated to reduce the duration of hospitalization and healthcare costs.16 However, this should not come at the price of patient safety and we should not forget that postprocedural conduction disorders are frequent complications. Therefore, it appears reasonable to monitor patients for 24-48 hours after TAVI. Finally, negative dromotropic medication such as betablockers, verapamil, amiodarone or digoxin should be discontinued periprocedurally to reduce the incidence of high-degree AV blocks and the need for a permament pacemaker.7,17

ST is a consultant and proctor for Boston Scientific, New Valve Technology and Abbott Vascular. He has received institutional research grants from Boston Scientific and Fumedica, has received speaker honoraria from Medtronic. He holds equity in Hi-D Imaging.