Left ventricular versus biventricular pacing: a randomized comparative study evaluating mid-term electromechanical...

Area of Science:

• Cardiology
• Electrophysiology
• Heart Failure Management

Background:

• Left ventricular (LV) pacing is a proposed alternative to biventricular (BIV) pacing for heart failure (HF) patients.
• Limited comparative data exist on the mid-term electromechanical effects of LV versus BIV pacing.

Purpose of the Study:

• To compare the clinical and echocardiographic effects of LV pacing against BIV pacing.
• To evaluate mid-term outcomes in a randomized study.

Main Methods:

• 22 patients with chronic HF and left bundle branch block were randomized to LV or BIV pacing.
• Device implantation with LV/BIV pacing capabilities was performed.
• Patients were assessed pre- and post-implantation (3 months) using clinical examination, ECG, and echocardiography with pulsed tissue Doppler imaging.

Main Results:

• LV pacing demonstrated similar improvements in clinical parameters and LV ejection fraction compared to BIV pacing at 3 months.
• Both pacing methods improved intraventricular dyssynchrony, with LV pacing showing a significant reduction in septal-to-lateral delay.
• BIV pacing, but not LV pacing, led to significant reductions in interventricular mechanical delay and QRS duration.

Conclusions:

• LV pacing provides clinical benefits comparable to BIV pacing at mid-term follow-up.
• LV pacing improves intraventricular dyssynchrony, independent of interventricular dyssynchrony and QRS duration.
• Echocardiographic assessment of intraventricular dyssynchrony is a suitable method for evaluating chronic response to LV pacing.