This study is a prospective, single-arm, target value clinical trial. We plan to prospectively enroll and follow 24 patients across three centers nationwide who have a low baseline heart rate (HR ≤ 60 bpm), meet the indication for permanent pacemaker implantation, and have right-sided heart failure with severe or greater tricuspid regurgitation. All patients will undergo pacemaker implantation using left bundle branch pacing (LBBP), and the pacing rate will be uniformly increased to 90 bpm (reduced to 80-85 bpm in case of intolerance). Patients will be followed for 6 months to evaluate the effects of heart-rate increase on hemodynamics, heart failure symptoms, and physical function in patients with right-sided heart failure.