Prognostic Implications of QRS Duration in Third-Degree Atrioventricular Block Patients with Heart Failure Treated...

Area of Science:

• Cardiology
• Medical Devices
• Heart Failure Research

Background:

• Cardiac resynchronization therapy (CRT) is beneficial for heart failure (HF) patients with third-degree atrioventricular block (AVB).
• Optimal patient selection for CRT remains a challenge.
• QRS duration is a potential but not fully established predictor of CRT efficacy in this population.

Purpose of the Study:

• To evaluate the predictive value of baseline QRS duration for CRT efficacy in patients with third-degree AVB and HF.
• To identify specific QRS duration thresholds associated with improved outcomes post-CRT.

Main Methods:

• A cohort of 72 patients with third-degree AVB and HF undergoing CRT implantation was analyzed.
• Patients were stratified into three groups based on baseline QRS duration: <120 ms, 120-149 ms, and ≥150 ms.
• CRT response, changes in left ventricular volumes and ejection fraction, survival rates, and primary endpoint events were assessed at 12 months.

Main Results:

• CRT response rates were significantly higher in patients with longer QRS durations (76.5% for ≥150 ms vs. 30.3% for <120 ms, P=0.008).
• Significant improvements in left ventricular remodeling and function were observed across all groups, with the greatest changes in the ≥150 ms group.
• QRS duration ≥150 ms was identified as an independent prognostic factor for CRT efficacy and associated with reduced primary endpoint events.

Conclusions:

• A baseline QRS duration of ≥150 ms is a robust predictor of successful CRT outcomes in patients with third-degree AVB and HF.
• Utilizing QRS duration ≥150 ms can aid in the appropriate selection of patients for CRT, optimizing treatment efficacy and prognosis.