Comparison of efficacy of left bundle branch area pacing and biventricular pacing in patients with dilated cardiomyopathy

Introduction: Left bundle branch area pacing (LBBAP) is a type of conduction system pacing (CSP), and is often used as an alternative to traditional biventricular pacing (BIVP).For patients with dilated cardiomyopathy, there is still a lack of comparison between the efficacy of LBBAP and BIVP, and the different efficacy of LBBAP in patients with left bundle branch block(LBBB) or atrioventricular block(AVB). Methods 124 patients with dilated cardiomyopathy were retrospectively collected and divided into LBBAP group (n = 66) and BIVP group (n = 58) according to different surgical methods. Preoperative electrocardiogram (ECG), echocardiogram, clinical cardiac function grading, intraoperative implantation parameters, and follow-up results at 1, 6, and 12 months after pacemaker implantation of all patients were collected. The two groups of data were compared and subgroup analysis was conducted to explore the different therapeutic effects of LBBAP on patients with CLBBB and patients with AVB respectively. Results Compared with BIVP, LBBAP produces lower and stable pacing threshold and shorter operation time. LBBAP reduced QRSd significantly more than BIVP (47.65 ± 17.94 vs 24.41 ± 15.80 ms, p < 0.001). It should be emphasized that LBBAP and BIVP improved left ventricular ejection fraction(LVEF), left atrial diameter(LAD), left ventricular internal diameter at end-diastole(LVIDD) and New York Heart Association(NYHA) class of patients with dilated cardiomyopathy compared with baseline, but LBBAP improved more significantly than BIVP. In addition, the number of readmissions of patients receiving LBBAP was significantly lower than that of BIVP group (p = 0.004). Subgroup analysis showed that the improvement of cardiac function was related to the correction of electrical conduction asynchrony; In the LBBAP group, the improvement of LVIDD in CLBBB patients was significantly higher than that in AVB patients (11.30 ± 7.24mm vs. 6.61 ± 5.54 mm). Conclusions Compared with BIVP, LBBAP can better optimize electrical synchronization and improve cardiac function and clinical outcome and can be the first choice for patients with cardiac conduction pathway block. LBBAP has a better effect on improving left ventricular structure in patients with CLBBB than in patients with AVB.