Author + information
- Received August 28, 2002
- Revision received March 7, 2003
- Accepted April 8, 2003
- Published online December 17, 2003.
- Angelo Auricchio, MD, PhD*,* (, )
- Christoph Stellbrink, MD†,
- Christian Butter, MD‡,
- Stefan Sack, MD§,
- Jürgen Vogt, MD∥,
- Anand Ramdat Misier, MD, PhD¶,
- Dirk Böcker, MD#,
- Michael Block, MD**,
- Johannes H Kirkels, MD, PhD††,
- Pacing Therapies in Congestive Heart Failure (PATH-CHF) II Study Group,
- Andrew Kramer, PhD‡‡,
- Etienne Huvelle, MD, MSEE‡‡,
- Guidant Heart Failure Research Group
- ↵*Reprint requests and correspondence:
Dr. Angelo Auricchio, Department of Cardiology, University Hospital, Leipzigerstr. 44, 39120 Magdeburg, Germany.
Objectives We assessed the clinical efficacy of single-site left ventricular (LV) pacing and determined the impact of baseline conduction delay severity on the magnitude of benefit.
Background Multisite biventricular pacing can improve heart failure (HF) symptoms in patients with an intraventricular conduction delay by resynchronizing abnormal ventricular contractions and improving LV systolic function.
Methods Eighty-six patients with at least New York Heart Association functional class II HF, chronic LV systolic dysfunction, normal sinus rhythm, and a QRS interval over 120 ms were implanted for atrial-synchronized LV pacing. The single-blinded, randomized, controlled, crossover study stratified patients 1:1 by the baseline QRS interval into long (QRS >150 ms) and short (QRS 120 to 150 ms) groups, which were compared during a three-month period of active (univentricular) pacing and a three-month period of inactive (ventricular inhibited) pacing. The primary end point was peak oxygen consumption (Vo2) followed by anaerobic threshold, distance walked in 6 min, and quality-of-life questionnaire score.
Results Twelve patients were withdrawn before randomization and 17 could not complete both study periods. The short QRS group did not improve in any end point with active pacing. For the long QRS group, peak Vo2increased 2.46 ml/min/kg (p < 0.001), the anaerobic threshold increased 1.55 ml/min/kg (p < 0.001), the distance walked in 6 min increased 47 m (p = 0.024), and the quality-of-life score improved 8.1 points (p = 0.004).
Conclusions Left ventricular pacing significantly improves exercise tolerance and quality of life in patients with chronic HF, LV systolic dysfunction, and a QRS interval over 150 ms.
☆ This study was supported entirely by an unrestricted grant from Guidant Corp., St. Paul, Minnesota.
- Received August 28, 2002.
- Revision received March 7, 2003.
- Accepted April 8, 2003.
- American College of Cardiology Foundation