Background

Permanent pacemaker implantation (PPI) after transcatheter valve implantation (TAVI) is a common complication. Preexisting right bundle branch block (RBBB) is a strong risk factor for PPI after TAVI. However, a patient-specific approach for risk stratification in this subgroup is missing / not yet established.

Methods

We investigated TAVI-patients with preexisting RBBB to stratify risk factors for PPI and 1-year-mortality, by detailed analysis of ECG data, RBBB morphology and degree of calcification in the implantation area assessed by computed tomography angiography.

Results

Between 2010 and 2018, 2129 patients with severe aortic valve stenosis underwent TAVI at our institution. Among these, 98 pacemaker-naïve patients with preexisting RBBB underwent TAVI procedure. PPI because of relevant conduction disturbances (CD) was necessary in 43 (43.9%) patients. PPI was more frequently indicated in women (62.1% vs. 32.8%, p=0.004) and in men undergoing a self-expandable valve (58.3% vs. 26.5%, p=0.035). ECG data (heart rhythm, PQ, QRS, QT) and RBBB morphology had no influence on PPI rate, whereas the degree of calcification in the left septal His-/left bundle branch-area (the acoronary left ventricular outflow (LVOT) tract) was significantly higher in patients with PPI (94.2 ±140.1mm³ vs. 52.5 ±161.9mm³, p=0.036). Overall 1-year-mortality was comparable among patients with or without PPI (14.0% vs. 16.4%; p=0.697). In contrast, an increased 1-year mortality (35.7%; p=0.020) was found in atrial fibrillation patients without PPI.

Conclusions

Patients with RBBB undergoing TAVI have a high risk of PPI. Among this subgroup, female patients, male patients with balloon-expandable valve types, patients with high load/degree of acoronary LVOT calcification and patients with atrial fibrillation need enhanced surveillance for CD after procedure.