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Background Left bundle branch block ( LBBB ) is common after transcatheter aortic valve implantation ( TAVI ) and is an indicator of subsequent high‐grade atrioventricular block ( HAVB ). No standardized protocol is available to identify LBBB patients at risk for HAVB . The aim of the current study was to evaluate the safety and efficacy of an electrophysiology study tailored strategy in patients with LBBB after TAVI . Methods and Results We prospectively analyzed consecutive patients with LBBB after TAVI . An electrophysiology study was performed to measure the HV ‐interval the day following TAVI . In patients with normal His‐ventricular ( HV )‐interval ≤55 ms, a loop recorder was implanted ( ILR ‐group), whereas pacemaker implantation was performed in patients with prolonged HV ‐interval >55 ms ( PM ‐group). The primary end point was occurrence of HAVB during a follow‐up of 12 months. Secondary end points were symptoms, hospitalizations, adverse events because of device implantation or electrophysiology study, and death. Of 373 patients screened after TAVI , 56 patients (82±6 years, 41% male) with LBBB were included. HAVB occurred in 4 of 41 patients (10%) in the ILR ‐group and in 8 of 15 patients (53%) in the PM ‐group ( P <0.001). We did not identify other predictors for HAVB than the HV interval. The negative predictive value for the cut‐off of HV 55 ms to detect HAVB was 90%. No HAVB ‐related syncope occurred in the 2 groups. Conclusions An electrophysiology study tailored strategy to LBBB after TAVI with a cut‐off of HV >55 ms is a feasible and safe approach to stratify patients with regard to developing HAVB during a follow‐up of 12 months.

Background-Transseptal puncture with a conventional mechanical technique can fail because of a resistant interatrial septum. We evaluated the efficacy and safety of a new method to cross-resistant septae by transmitting radiofrequency (RF) energy through the transseptal needle. Methods and Results-Among 269 consecutive transseptal punctures, 13 (5%) were unsuccessful in 12 different patients (11 men aged 52Ϯ12 years) using the conventional Brockenbrough technique. All 12 patients had previously undergone at least 1 transseptal catheterization. The needle position in relation to the fossa ovalis was assessed by fluoroscopy in orthogonal views and was confirmed with contrast injection and by visualizing the characteristic "tenting" of the fossa ovalis. Before using RF energy, there were a median of 6 unsuccessful attempts to perforate the septum conventionally, with 1 pericardial puncture (with a nonsignificant effusion). RF transseptal puncture was then performed by delivering unipolar RF with manual contact between the ablation catheter and the proximal extremity of the needle at the patient's groin. RF transseptal puncture was achieved at the first attempt in all patients within a median of 1 second (interquartile range, 1 to 4) and without any complication. The only parameter predictive of a septum resistant to conventional puncture was the total number of transseptal catheterizations (3.2Ϯ1 versus 1.8Ϯ1, PϽ0.001). Conclusion-Transmission

The study reports preliminary findings suggesting a possible link between ESR polymorphisms and the occurrence of TS. Larger studies are needed to confirm our results.