The relationship between ventricular electrical delay and left ventricular remodelling with cardiac resynchronization...

Area of Science:

• Cardiology
• Electrophysiology
• Heart Failure Management

Background:

• Cardiac resynchronization therapy (CRT) is used for heart failure patients with electrical dyssynchrony.
• Predicting CRT response remains a challenge.

Purpose of the Study:

• To evaluate the relationship between left ventricular (LV) electrical delay (QLV interval) and patient outcomes.
• To assess if QLV can predict response to CRT.

Main Methods:

• A prospective substudy of the SMART-AV Trial involving 426 patients with advanced heart failure undergoing CRT defibrillator implantation.
• QLV measured from surface ECG to LV electrogram; LV volumes assessed by echocardiography; quality of life (QOL) by questionnaire.

Main Results:

• Reverse remodeling response rates increased progressively with shorter QLV durations (38.7% to 68.4%).
• Quality of life response rates also increased with shorter QLV (50% to 72%).
• Patients with the shortest QLV had a 3.21-fold increased odds of reverse remodeling response.

Conclusions:

• LV electrical delay (QLV) is independently associated with reverse remodeling and improved QOL in CRT patients.
• Acute QLV measurements may aid in optimizing LV lead placement for CRT.