Left Bundle Branch Block after TAVR: What Is Its Impact?

Courtesy of Dr. Juan Manuel Pérez.

Left bundle branch block (LBBB) is a common complication following transcatheter aortic valve replacement (TAVR), which can be either transient or persistent (pLBBB). Its long-term impact remains uncertain, though previous studies have linked it to increased risk of ventricular dysfunction and heart failure, with conflicting results as regards mortality.

This prospective, multicenter, observational study included 551 patients undergoing TAVR from 2012 to 2021 at a Swiss center, excluding those with prior conduction disorders, preexisting pacemakers, valve-in-valve procedures, or in-hospital mortality. Patients were classified into two groups: those with pLBBB at discharge (n=85; 15%) and those without LBBB or with transient LBBB (n=466; 85%), and followed up to five years. 

Primary endpoint was all-cause mortality and hospitalization for heart failure. Secondary outcomes included need for permanent pacemaker implantation (PPM) and changes in left ventricular ejection fraction (LVEF).

Population mean age was 81, with 58 ± 11% baseline LVEF. 43% of patients were hypertensive, 32% diabetic type 2, and 25% had atrial fibrillation. 78% of cases received a self-expanding valve, and 22% a balloon-expandable valve; predilation was performed in 65% of procedures. The transfemoral approach was used in 92% of patients.

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pLBBB was not associated with increased all-cause mortality (HR 1.14; 95% CI: 0.92-1.41; p=0.24) but was linked to higher risk of hospitalization for heart failure (HR 1.34; 95% CI: 1.01-1.76; p=0.04). No significant differences were found in PPM rate (HR 1.45; 95% CI: 0.96-2.18; p=0.07). However, a significant reduction in LVEF was observed among pLBBB patients at follow-up (from 58% ± 11% to 55% ± 12%; p=0.03), while LVEF remained stable among no LBBB patients, or those with transient LBBB (61% ± 10% vs. 60% ± 10%; p=0.45).

Implantation was significantly deeper in pLBBB patietns (4.0 ± 1.8 mm vs. 3.3 ± 1.8 mm; p<0.01), making this the main predictor of pLBBB. Other contributing factors were also analyzed, including a smaller left ventricular outflow tract diameter and aortic annulus and interventricular septum calcification.

Conclusion

In conclusion, pLBBB occurred in 15% of patients without a history of conduction disorders or pacemakers and was associated with higher risk of hospitalization for heart failure and progressive LVEF deterioration. However, no significant impact was identified on overall mortality or the need for pacemaker implantation.

Original Title: Long-Term Outcomes After Transcatheter Aortic Valve Replacement Complicated by New-Onset Persistent Left Bundle Branch Block.

Reference: Carmen Hodel et al. Catheterization and Cardiovascular Interventions, 2025.