Article

Reverse remodeling and the risk of ventricular tachyarrhythmias in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy).

Cardiology Division, University of Rochester Medical Center, Rochester, New York 14642, USA.
Journal of the American College of Cardiology (impact factor: 14.16). 06/2011; 57(24):2416-23. DOI:10.1016/j.jacc.2010.12.041 pp.2416-23
Source: PubMed

ABSTRACT We aimed to evaluate the relationship between echocardiographic response to cardiac resynchronization therapy (CRT) and the risk of subsequent ventricular tachyarrhythmias (VTAs).
Current data regarding the effect of CRT on the risk of VTA are limited and conflicting.
The risk of a first appropriate implantable cardioverter-defibrillator (ICD) therapy for VTA (including ventricular tachycardia, ventricular fibrillation, and ventricular flutter) was compared between high- and low-echocardiographic responders to CRT defibrillator (CRT-D) therapy (defined as ≥ 25% and <25% reductions, respectively, in left ventricular end-systolic volume [LVESV] at 1 year compared with baseline) and ICD-only patients enrolled in the MADIT-CRT (Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy).
The cumulative probability of a first VTA at 2 years after assessment of echocardiographic response was highest among low responders to CRT-D (28%), intermediate among ICD-only patients (21%), and lowest among high responders to CRT-D (12%), with p < 0.001 for the overall difference during follow-up. Multivariate analysis showed that high responders to CRT-D experienced a significant 55% reduction in the risk of VTA compared with ICD-only patients (p < 0.001), whereas the risk of VTA was not significantly different between low responders and ICD-only patients (hazard ratio [HR]: 1.26; p = 0.21). Consistently, assessment of response to CRT-D as a continuous measure showed that incremental 10% reductions in left ventricular end-systolic volume were associated with corresponding reductions in the risk of subsequent VTA (HR: 0.80; p < 0.001), VTA/death (HR: 0.79; p < 0.001), ventricular tachycardia (HR: 0.80; p < 0.001), and ventricular fibrillation/ventricular flutter (HR: 0.75; p = 0.044).
In patients with left ventricular dysfunction enrolled in the MADIT-CRT trial, reverse remodeling was associated with a significant reduction in the risk of subsequent life-threatening VTAs. (Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy [MADIT-CRT]; NCT00180271).

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

2 years
 
cardiac resynchronization therapy
 
continuous measure
 
corresponding reductions
 
CRT defibrillator
 
cumulative probability
 
first appropriate implantable cardioverter-defibrillator
 
first VTA
 
hazard ratio [HR]
 
ICD-only patients
 
incremental 10% reductions
 
low responders
 
low-echocardiographic responders
 
Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy
 
Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy [MADIT-CRT]
 
Multivariate analysis
 
subsequent life-threatening VTAs
 
subsequent VTA
 
ventricular fibrillation
 
ventricular tachycardia