Coronary sinus lead delay index for optimization of coronary sinus lead placement

Abstract

Aim: Optimization of coronary sinus (CS) lead position to the latest activated left ventricular (LV) area is important to increase cardiac resynchronization therapy (CRT) response. We aimed to detect the relationship between coronary sinus lead delay index (CSDI) and echocardiographic, electrocardiographic response to CRT treatment. Methods: We prospectively included 137 consecutive patients with heart failure (HF) diagnosis, QRS ≥ 120 ms, left bundle branch block (LBBB), New York Heart Association score (NYHA) II–IV, LV ejection fraction (LVEF) <35% and scheduled for CRT (84 male, 53 female; mean age 65.1 ± 10.1 years). Echocardiographic CRT response was defined as ≥15% reduction in LV end-systolic volume (LVESV). CS lead sensing delay was calculated as the time interval from the onset of surface QRS wave to the onset of depolarization wave recorded from the CS lead by using the CS pacing lead as a bipolar electrode. CSDI was calculated by dividing the CS lead sensing delay by the QRS duration. Results: LVESV reduction was associated with baseline QRS width (r =.257, p =.002), QRS narrowing (r =.396, p