title: The impact of nonsustained ventricular tachycardia on reverse remodeling, heart failure, and treated ventricular tachyarrhythmias in MADIT-CRT.
abstract: BACKGROUND
  This study determined whether the presence of nonsustained ventricular tachycardia (NSVT) was predictive of clinical events in MADIT-CRT (multicenter automatic defibrillator implantation trial-cardiac resynchronization therapy) patients treated with CRT-defibrillator.
  
  
  RESULTS
  We analyzed 24-hour Holters for the presence of NSVT. Patients were then stratified by the etiology (ischemic or nonischemic) of cardiomyopathy. The impact of NSVT on heart failure events (HF), implantable cardioverter-defibrillator (ICD) therapy for rapid ventricular tachycardia (VT) or fibrillation (VF), and reverse remodeling was determined. At least a single episode of NSVT was recorded in 483 (49%) patients. These patients had a higher burden of premature ventricular contractions, lower percentage of biventricular (BiV) pacing, and significantly less reduction in left ventricular end-diastolic and end-systolic volumes. The risk of HF was significantly greater in patients with nonischemic cardiomyopathy and NSVT (hazard ratio [HR] 2.89; 95% confidence interval [CI]: 1.49-5.61; P = 0.002). The risk of rapid VT/VF was significantly greater (in both ischemic and nonischemic patients) when NSVT was observed (HR 2.06; 95% CI: 1.30-3.26; P = 0.002 in ischemic patients; HR 3.09; 95% CI: 1.80-5.28; P < 0.001 in nonischemic patients).
  
  
  CONCLUSIONS
  MADIT-CRT patients with NSVT had a high burden of ventricular ectopy, lower percentage of BiV pacing, and less reverse remodeling. These patients had an increase in HF (in nonischemic cardiomyopathy patients) and rapid VT/VF ICD therapies (in ischemic and nonischemic patients). These findings may have implications for the management of nonsustained ventricular ectopy in CRT patients.
authors.affiliation: Arrhythmia Institute, Valley Hospital Health System, Ridgewood, New Jersey and New York, New York, USA.
authors.forename: Suneet
authors.initials: S
authors.lastname: Mittal
authors.forename: Mehmet K
authors.initials: MK
authors.lastname: Aktas
authors.forename: Arthur J
authors.initials: AJ
authors.lastname: Moss
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.forename: Valentina
authors.initials: V
authors.lastname: Kutyifa
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Steinberg
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zareba
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000401:mortality* / Q000706:statistics & numerical data*; D015897:Comorbidity; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D015996:Survival Rate; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control*; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D020257:Ventricular Remodeling
keywords: cardiac resynchronization therapy; nonsustained ventricular tachycardia; reverse remodeling