Predictors of right ventricular pacing-induced left ventricular dysfunction in pacemaker recipients with preserved...

Area of Science:

• Cardiology
• Electrophysiology
• Heart Failure

Background:

• Chronic right ventricular pacing can lead to electrical and mechanical dyssynchrony.
• This dyssynchrony may result in deterioration of left ventricular ejection fraction (LVEF), termed pacing-induced cardiomyopathy (PICM).
• Previous studies reported PICM incidence between 10-26%, with undefined predictors.

Purpose of the Study:

• To investigate the incidence of PICM in patients with preserved LVEF undergoing pacemaker implantation.
• To identify predictors for the development of PICM.

Main Methods:

• Retrospective study of 320 patients with single- or dual-chamber pacemaker implantation.
• Exclusion of patients with implantable cardioverter defibrillators or cardiac resynchronization therapy.
• Inclusion of patients with baseline LVEF ≥ 50%, with a mean follow-up of 4.7 years.

Main Results:

• The incidence of PICM was 7.5% in the studied cohort.
• Predictors for PICM included wider native QRS duration (>140 ms), wider paced QRS duration (>150 ms), low-normal pre-implantation ejection fraction (<56%), and increased LV end-diastolic diameter (>53 mm) and LV end-systolic diameter (>38 mm).
• No association was found between the burden or site of right ventricular pacing and PICM development.

Conclusions:

• Right ventricular pacing-induced left ventricular dysfunction (PICM) occurs in 7.5% of patients with preserved baseline LVEF.
• Wider native and paced QRS durations, lower pre-implantation ejection fraction, and increased LV dimensions are key predictors of PICM.
• These findings aid in identifying patients at higher risk for developing PICM.