Heart failure decompensation and all-cause mortality in relation to percent biventricular pacing in patients with heart failure: is a goal of 100% biventricular pacing necessary?

J Am Coll Cardiol. 2009 Jan 27;53(4):355-60. doi: 10.1016/j.jacc.2008.09.043.


Objectives: The goal of this analysis was to determine the appropriate biventricular pacing target in patients with heart failure (HF).

Background: Cardiac resynchronization therapy (CRT) decreases the risk of death and HF hospitalization. However, the appropriate amount of biventricular pacing is ill-defined.

Methods: Mortality and HF hospitalization data from patients undergoing CRT in 2 trials (CRT RENEWAL [Cardiac Resynchronization Therapy Registry Evaluating Patient Response with RENEWAL Family Devices] and REFLEx [ENDOTAK RELIANCE G Evaluation of Handling and Electrical Performance Study]; n = 1,812) were analyzed in a post-hoc fashion. Subjects were grouped based on percent biventricular pacing quartiles with the use of Kaplan-Meier survival analysis.

Results: Subjects were age 72 +/- 11 years; 72% were men and 67% had coronary artery disease. Subjects paced 93% to 100% (quartiles 2 to 4) had a 44% reduction in hazard of an event compared with subjects paced 0% to 92% (quartile 1; hazard ratio [HR]: 0.56, p < 0.00001). Subjects paced 98% to 99% (quartile 3) had similar outcomes as subjects paced 93% to 97% (quartile 2; HR: 0.97, p = 0.82). Subjects paced 100% (quartile 4) had similar outcomes as subjects paced 98% to 99% (HR: 0.78, p = 0.17). There was a significant interaction between a history of atrial arrhythmia and percent pacing. Subjects with a history of atrial arrhythmia were more likely to be paced < or =92% (p < 0.001).

Conclusions: For CRT patients in this retrospective analysis, the greatest magnitude of benefit was observed with >92% biventricular pacing.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Cardiac Pacing, Artificial*
  • Female
  • Heart Failure / mortality*
  • Heart Failure / therapy*
  • Heart Ventricles
  • Humans
  • Male
  • Middle Aged
  • Pacemaker, Artificial
  • Retrospective Studies
  • Risk Factors
  • Severity of Illness Index