Send to:

Choose Destination
See comment in PubMed Commons below
Heart Rhythm. 2013 Jul;10(7):943-50. doi: 10.1016/j.hrthm.2013.04.006. Epub 2013 Apr 29.

Clinical significance of ventricular tachyarrhythmias in patients treated with CRT-D.

Author information

  • 1University of Rochester Medical Center, Rochester, New York 14642, USA. Valentina.Kutyifa@heart.



Data on the outcome of cardiac resynchronization therapy with defibrillator (CRT-D) in patients developing ventricular arrhythmias are limited.


To evaluate the prognostic value of ventricular tachycardia (VT) or ventricular fibrillation (VF) episodes by heart rate in patients enrolled in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy trial.


Slow VT was defined as VTs with heart rate < 200 beats/min. Fast VT with a heart rate ≥200 beats/min and VF (>250 beats/min) were considered as a combined category. Primary end point was heart failure (HF) or death. Secondary end point included all-cause mortality.


There were 228 (12.7%) patients with slow VT and 198 (11.1%) with fast VT/VF. In time-dependent analysis, slow VT was associated with an increased risk of HF/death in CRT-D patients with left branch bundle block (LBBB; hazard ratio [HR] 3.19; 95% confidence interval [CI] 1.83-5.55; P < .001), but not in patients with implantable cardioverter-defibrillator (ICD) (HR 1.03; 95% CI 0.52-2.19; P = .867; interaction P value = .017). CRT-D patients with LBBB and fast VT/VF doubled their risk of HF/death compared to ICD patients (interaction P value = .06). Slow VT events were also predictive of death in CRT-D patients with LBBB (HR 3.48; 95% CI 1.66-7.28; P < .001), but not in ICD patients (interaction P value = .06). Slow VTs were highly predictive of subsequent fast VT/VF (HR 4.33; 95% CI 3.01-6.24; P < .001).


Slow VT episodes are predictive of subsequent fast VT/VF. Slow VT and fast VT/VF episodes in CRT-D patients are associated with an increased risk of subsequent HF/death. CRT-D-treated LBBB patients with slow VTs have a significantly higher risk of mortality.

Published by Elsevier Inc.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk