Left bundle branch area pacing in patients with Chagasic cardiomyopathy

Introduction Patients with Chagasic cardiomyopathy (CCM) are frequently underrepresented, with little information on the outcomes of patients with CCM undergoing cardiac resynchronization therapy (CRT). Left bundle branch area pacing (LBBAP) is increasingly being used as an alternative strategy to achieve CRT. However, there is little information on the outcomes of patients with CCM undergoing LBBAP. Purpose To determine the outcomes of patients with CCM undergoing LBBAP for CRT compared to other types of cardiomyopathies. Methods In this multicenter observational study, patients with heart failure (HF) and a left ventricular ejection fraction (LVEF) <40% undergoing LBBAP CRT between September 2020 and March 2025 were included. Patients were divided according to the etiology of their HF into ischemic cardiomyopathy (ICM), non-ischemic cardiomyopathy (NICM), and CCM. Baseline and procedural characteristics were evaluated. Categorical variables are expressed as percentages; continuous variables as median and interquartile range. The primary outcome was the composite outcome of HF-related hospitalization and all-cause mortality. Results A total of 372 patients (female 37.1% age 70[63-77] years) with a median follow-up of 480 [221-803] days, were included. Regarding baseline characteristics (Table 1), there were significant differences in the prevalence of diabetes, as well as in the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEi/ARB) and ARB/neprilysin inhibitors (ARNI), with no other significant differences. Procedural and fluoroscopy times were similar between groups; however, CCM patients had longer V6-V1 intervals as well as shorter paced QRS durations. During follow-up, there were no significant differences in the primary outcome or the risk of HF-related hospitalization between the 3 groups (Figure 1). However, patients with CCM had the lowest LVEF improvement (p=0.003). Conclusions Compared to patients with ICM and NICM, patients with CCM have similar procedural characteristics. Despite the significant differences in the mechanism of HF in patients with CCM and the lower improvement in LVEF after LBBAP, long-term outcomes after LBBAP CRT appear to be the same as in other HF etiologies.