Clinical Efficacy and Safety of Left Bundle Branch Area Pacing Using Quantitative Guidance of Multimodal Data in the Treatment of Heart Failure

Heart failure is a common chronic cardiovascular disease that seriously impairs patients' quality of life and long-term prognosis. When heart failure is complicated by complete left bundle branch block, the electrical signals that regulate orderly heart contraction cannot be transmitted normally along the left conduction pathway, causing the left and right ventricles to contract out of sync. This will gradually weaken the heart's pumping capacity, leading to symptoms such as exertional shortness of breath, persistent fatigue and body edema, and significantly increasing the risk of repeated hospital admissions and premature death.

Traditional biventricular pacing is the standard treatment recommended by international clinical guidelines for this condition. By implanting pacing leads in both ventricles to deliver synchronized electrical stimulation, it restores cardiac synchrony, improves cardiac function and reduces mortality in most eligible patients. However, the placement of left ventricular leads is entirely dependent on the anatomy of the coronary venous system. Due to wide individual differences in venous structure, many patients encounter intraoperative difficulties such as failed coronary sinus intubation, absence of suitable target veins, phrenic nerve stimulation, high pacing thresholds and postoperative lead displacement. More importantly, approximately 30% to 40% of patients still show no significant improvement in cardiac function or symptoms even after optimized device programming, a condition known as non-response to cardiac resynchronization therapy.

Left bundle branch area pacing is an innovative physiological pacing technique originally developed in China. It advances a pacing lead through the ventricular septum to directly activate the heart's intrinsic conduction bundle, allowing electrical impulses to spread along the natural conduction pathway and restore ventricular synchrony. Previous single-center observational studies have shown that this technique features stable long-term pacing parameters, relatively low operative difficulty and a favorable safety profile, and can achieve satisfactory cardiac resynchronization effects. Nevertheless, there is still a lack of high-quality multicenter randomized controlled evidence to confirm its long-term clinical hard endpoint benefits. In addition, current implantation operations largely rely on the personal experience of operators, without a unified quantitative positioning standard.

This multicenter prospective randomized controlled study is led by the Second Affiliated Hospital of Nanchang University, with three other tertiary general hospitals participating. A total of 100 eligible heart failure patients with left bundle branch block and left ventricular ejection fraction ≤ 40% will be enrolled. All participants have received at least 3 months of standardized guideline-directed anti-heart failure drug therapy before enrollment, and will be randomly assigned to two groups at a 1:1 ratio. One group will receive left bundle branch area pacing guided by multimodal quantitative data, and the other will receive traditional biventricular pacing. If the initially assigned pacing strategy cannot be successfully implemented during surgery, the patient will cross over to the alternative approach to ensure clinical safety and therapeutic effect.

After the implantation procedure, all patients will receive regular follow-up every 3 months for at least 1 year. During follow-up, the research team will perform examinations including 12-lead electrocardiogram, echocardiogram, 6-minute walk test and pacemaker device interrogation, and systematically record clinical events such as all-cause death, heart failure rehospitalization, malignant arrhythmia and procedure-related complications. The core goal of this study is to compare the incidence of the composite endpoint of all-cause death and heart failure rehospitalization between the two groups, and verify whether multimodal quantitative-guided left bundle branch area pacing can bring superior long-term clinical benefits to heart failure patients. The findings are expected to provide reliable evidence for the clinical application of this technique, help establish standardized quantitative implantation standards, and offer a more optimized treatment option for more heart failure patients.