Impact of Pacing Site on QRS Duration and Its Relationship to Hemodynamic Response in Cardiac Resynchronization Therapy for Congestive Heart Failure
Article first published online: 24 JUL 2014
© 2014 Wiley Periodicals, Inc.
Journal of Cardiovascular Electrophysiology
Volume 25, Issue 9, pages 1012–1020, September 2014
How to Cite
DERVAL, N., BORDACHAR, P., LIM, H. S., SACHER, F., PLOUX, S., LABORDERIE, J., STEENDIJK, P., DEPLAGNE, A., RITTER, P., GARRIGUE, S., DENIS, A., HOCINI, M., HAISSAGUERRE, M., CLEMENTY, J. and JAÏS, P. (2014), Impact of Pacing Site on QRS Duration and Its Relationship to Hemodynamic Response in Cardiac Resynchronization Therapy for Congestive Heart Failure. Journal of Cardiovascular Electrophysiology, 25: 1012–1020. doi: 10.1111/jce.12464
- Issue published online: 4 SEP 2014
- Article first published online: 24 JUL 2014
- Accepted manuscript online: 2 JUN 2014 03:51AM EST
- Manuscript Accepted: 17 APR 2014
- Manuscript Revised: 14 APR 2014
- Manuscript Received: 7 JAN 2014
- acute hemodynamic;
- cardiac resynchronization therapy;
- endocardial pacing;
- heart failure;
- implantable cardioverter defibrillator;
- left ventricular pacing
Electrical Impact of the Left Ventricular Pacing Site in CRT
Recent studies have demonstrated that left ventricular (LV) pacing site is a critical parameter in optimizing cardiac resynchronization therapy (CRT). The present study evaluates the effect of pacing from different LV locations on QRS duration (QRSd) and their relationship to acute hemodynamic response in congestive heart failure patients.
Methods and Results
Thirty-five patients with nonischemic dilated cardiomyopathy and left bundle branch block referred for CRT device implantation were studied. Eleven predetermined LV pacing sites were systematically assessed in random order: epicardial: coronary sinus (CS); endocardial: basal and mid-cavity (septal, anterior, lateral, and inferior), apex, and the endocardial site facing the CS pacing site. For each patient QRSd and +dP/dtmax during baseline (AAI) and DDD LV pacing at 2 atrioventricular delays were compared. Response to CRT was significantly better in patients with wider baseline QRSd (≥150 milliseconds). Hemodynamic response was inversely correlated to increase of QRSd during LV pacing (short atrioventricular [AV] delay: r = 0.44, P < 0.001; long AV delay: r = 0.59, P < 0.001). Compared to baseline, LV pacing at the site of shortest QRSd significantly improved +dP/dtmax (+18 ± 25%, P < 0.001) but was not superior to other conventional strategy (lateral wall, CS pacing, and echo-guided) and was inferior to a hemodynamically guided strategy.
In our study, we have demonstrated that changes of QRSd during LV pacing correlated with acute hemodynamic response and that LV pacing location was a primary determinant of paced QRSd. Although QRSd did not predict the maximum hemodynamic response, our results confirm the link between electrical activation and hemodynamic response of the LV during CRT.