Usefulness of Multisite Ventricular Pacing in Nonresponders to Cardiac Resynchronization Therapy

Area of Science:

• Cardiology
• Medical Devices
• Heart Failure Management

Background:

• Cardiac resynchronization therapy (CRT) is a standard treatment for heart failure with impaired myocardial function and delayed ventricular activation.
• A significant portion of patients (25%-40%) do not achieve a positive response to CRT.
• Left ventricular (LV) multisite pacing (MSP) is being investigated as a method to enhance CRT response rates.

Purpose of the Study:

• To evaluate the safety and efficacy of utilizing the LV MSP feature in patients who are non-responders to CRT.
• To assess the clinical composite score (CCS) changes and complication rates associated with LV MSP.

Main Methods:

• The Strategic Management to Improve CRT Using Multi-Site Pacing (SMART-CRT) trial enrolled 584 CRT-defibrillator recipients.
• 102 non-responders had the LV MSP feature activated and were evaluated at 6 and 12 months using the CCS.
• Safety was assessed by the complication-free rate, and efficacy by the proportion of patients with improved CCS.

Main Results:

• The LV MSP feature demonstrated a high complication-free rate of 99.0%, exceeding the performance goal of 90%.
• Approximately 51.3% of CRT non-responders showed an improved CCS from 6 to 12 months, surpassing the 5% performance goal.
• The LV MSP feature was associated with an estimated reduction of 3.6 months in CRT-defibrillator battery longevity.

Conclusions:

• LV MSP is a safe and effective strategy for managing CRT non-responders, achieving a conversion rate of around 50%.
• This approach offers a significant improvement in clinical outcomes for a substantial number of non-responding patients.
• LV MSP should be considered as a valuable option in the treatment algorithm for patients with heart failure who do not benefit from standard CRT.