Mid-Term Impact of Conduction System Pacing on Overall Cardiac Performance: A Non-Randomized, Prospective,...

Area of Science:

• Cardiology
• Electrophysiology
• Cardiac Imaging

Background:

• Conduction system pacing (CSP) may reduce pacing-induced cardiomyopathy (PICM) incidence compared to traditional methods.
• Previous studies primarily focused on left ventricular effects, necessitating a comprehensive assessment of all cardiac chambers.

Purpose of the Study:

• To evaluate medium-term echocardiographic changes in cardiac morphology and function across all heart chambers following CSP in patients with preserved to mid-range LVEF.
• To compare the effects of His bundle pacing (HBP) versus left bundle branch area pacing (LBBAP) on cardiac parameters.

Main Methods:

• Prospective enrollment of 128 patients with LVEF > 40% undergoing successful CSP for bradyarrhythmias.
• Complete 2D echocardiography at baseline and follow-up (mean 699 days) to assess ventricular volumes, ejection fraction, and chamber dimensions.
• Categorization of patients into HBP (n=38) and LBBAP (n=90) groups.

Main Results:

• A very low PICM incidence (2.9%) was observed.
• CSP significantly increased LVEF and decreased left ventricular end-diastolic and end-systolic volumes.
• Right ventricular function improved significantly, with no significant changes in atrial volumes or RV diameter. Tricuspid regurgitation showed worsening.
• No significant echocardiographic differences were noted between HBP and LBBAP groups.

Conclusions:

• Both HBP and LBBAP demonstrate comparable protective effects against adverse cardiac remodeling in all heart chambers.
• CSP is associated with a very low prevalence of PICM, even in patients with baseline preserved to mid-range LVEF.