The specific value of upgrading to left bundle branch area pacing in patients with pacing-induced cardiomyopathy or non-pacing-induced cardiomyopathy related upgrade status: A retrospective study.

Abstract

Left bundle branch area pacing (LBBaP) upgrade can improve cardiac function and clinical outcomes in patients with pacing-induced cardiomyopathy (PICM), but the specific value of LBBaP upgrade, especially compared with the cardiac function level before right ventricular pacing (RVP) in patients with PICM and non-pacing-induced cardiomyopathy-related upgrade status (Non-PICMUS) is still unknown. This study retrospectively enrolled 70 patients with LBBaP upgrade (38 patients with PICM and 32 patients with Non-PICMUS). All upgrade patients experienced three stages: before RVP (Pre-RVP), before LBBaP upgrade (Pre-LBBaP), and after LBBaP upgrade (Post-LBBaP). QRS duration (QRSd), lead parameters, echocardiographic indicators, and clinical outcomes evaluation were recorded at multiple time points. At the follow-up of 12 months, for PICM patients, left ventricular ejection fraction (LVEF) significantly increased from 36.6%±7.2% to 51.3%±8.7% Post-LBBaP (p<.001), and left ventricular end-diastolic diameter (LVEDD) significantly decreased from 61.5±6.4mm to 55.2±6.5mm Post-LBBaP (p<.001), but they both failed to restore the level Pre-RVP (both p<.001). For PICM patients, New York Heart Association (NYHA) classification, the number of moderate-to-severe heart failure (NYHA III-IV), and diuretics using rate after the LBBaP upgrade also could not restore to the level Pre-RVP (all p<.001). At the follow-up of 12 months, Non-PICMUS patients after the LBBaP upgrade had no significant improvement in LVEF, LVEDD, and NYHA classification (all p>.05). LBBaP upgrade effectively improved the cardiac function and clinical outcomes in PICM patients, but its effectiveness seemed to be limited as the deteriorated cardiac function cannot be completely reversed. For Non-PICMUS patients, the cardiac function and clinical outcomes Post-LBBaP had no significant improvement.