Left Bundle Branch Pacing (LBBP) has emerged as one of the most commonly used physiological pacing modalities in clinical practice. However, the key determinants of procedural success lie in the accurate intraoperative identification of proper LBB lead positioning and the prevention of cardiac perforation. Our previous research has established a methodology for Lumenless Lead (LLL) implantation under the guidance of continuous pacing monitoring, and this methodology has been further adapted for Stylet-driven Lead (SDL) implantation. The present study is designed as a multicenter, randomized controlled trial, aiming to compare the differences in efficacy and safety between LLL and SDL during LBBP procedures guided by continuous pacing monitoring, with the presence of S-V dissociation serving as the criterion for confirming optimal LBB lead positioning.

Inclusion Criteria:

• Symptomatic sick sinus syndrome (SSS);
• Complete or advanced atrioventricular block (AVB);
• Patients with heart failure complicated by left bundle branch block (LBBB) and biventricular dyssynchrony;
• Patients with atrial fibrillation (AF) complicated by refractory rapid ventricular rate who are scheduled for atrioventricular node ablation and permanent pacemaker implantation;
• Other patients who meet the indications for dual-chamber pacemaker implantation as specified in current guidelines

Exclusion Criteria:

• Patients who are ineligible for transvenous cardiac pacemaker implantation due to anatomical abnormalities, infections, or other factors;
• Patients with existing implantable cardiac electronic devices (ICEDs);
• Patients who opt for right-sided venous access for any reason;
• Patients with an expected survival of less than 1 year;
• Patients who have been enrolled in other clinical trials related to implantable cardiac electronic devices within 3 months prior to enrollment in this study.