not-yet-known not-yet-known not-yet-known unknown Introduction: Transcatheter aortic valve implantation (TAVI) is a treatment for severe aortic stenosis in high-risk and intermediate-risk patients unsuitable for surgery. Despite its minimally invasive nature, TAVI often leads to complications, including de novo left bundle branch block (LBBB), which increases the risk of complete atrioventricular (AV) block, heart failure, and sudden cardiac death. Current guidelines provide ambiguous recommendations for permanent pacemaker (PPM) implantation for patients with LBBB post-TAVI. This report aims to reevaluate the HV interval cutoff and explore alternative predictors for PPM decisions in patients with LBBB after TAVI. Case Description: A 79-year-old female with non-obstructive coronary artery disease and severe symptomatic aortic stenosis underwent TAVI with a 26 mm Edwards Resilia balloon-expandable valve. Pre-TAVI electrocardiography (ECG) showed sinus rhythm with a QRS duration of 98 ms. Post-TAVI, the patient developed a first-degree AV delay and new-onset LBBB. An electrophysiological study (EPS) performed 48 hours post-TAVI showed an HV interval of 61 ms. Despite this, the patient developed symptomatic complete heart block hours later, necessitating urgent PPM implantation. Discussion: This case questions the reliability of the HV interval as a standalone marker for pacemaker decisions in LBBB post-TAVI patients. The occurrence of complete heart block despite an HV interval below predictive values raises concerns about this parameter’s accuracy. Alternative predictors such as the delta HV interval and AH interval may provide better insights. Delayed EPS assessment might be more appropriate. Conclusion: Managing LBBB after TAVI is complex. Reevaluation of HV interval reliability and larger trials to establish accurate predictors and refine PPM implantation criteria post-TAVI are needed to improve patient outcomes.

The Left bundle branch area pacing (LBBAP) is a novel pacing strategy that utilizes the conduction system distal to the left bundle branch block level for direct activation of the left bundle and the right ventricular myocardium. Our meta-analysis compared the structural, electrophysiological, clinical, and procedural outcomes of LBBAP and Bi-ventricular pacing (BVP). The meta-analysis included two randomized control trials and showed significant reductions in left ventricular systolic and diastolic volumes with LBBAP compared to BVP, along with a statistically significant decrease in QRS duration, NYHA class, and heart failure hospitalizations. Fluoroscopic time was also significantly shorter in the LBBAP group. However, no significant change in LV ejection fraction was noted. Although not statistically significant, procedural complications were slightly higher in the LBBAP group. Our findings suggest that LBBAP may be a superior alternative to standard BVP in improving structural and electrophysiological components and clinical components of cardiomyopathy, including NYHA class and heart failure hospitalizations. LBBAP is a more physiological pacing strategy that results in normal ventricular activation and may be a viable alternative to BVP for cardiac synchronization therapy.