A simplified biventricular defibrillator with fixed long detection intervals reduces implantable cardioverter defibrillator (ICD) interventions and heart failure hospitalizations in patients with non-ischaemic cardiomyopathy implanted for primary prevention: the RELEVANT [Role of long dEtection window programming in patients with LEft VentriculAr dysfunction, Non-ischemic eTiology in primary prevention treated with a biventricular ICD] study.
OBJECTIVE
To investigate the efficacy and safety of a cardiac resynchronization therapy with cardioverter-defibrillator (CRT-D) device with simplified ventricular tachycardia management in patients with non-ischaemic heart failure (HF) and primary prevention implantable cardioverter defibrillator (ICD) indication.


RESULTS
Prospective, controlled, parallel, multicentre, non-randomized study enrolling 324 primary prevention non-ischaemic HF patients implanted with CRT-D devices from 2004 to 2007: Protect group, 164 patients implanted with a Medtronic Insync III Protect device and Control group, 160 patients utilizing other Medtronic CRT-D devices. Efficacy was assessed by computing appropriate and inappropriate detections and therapies during follow-up; safety compared hospitalizations and syncopal events between groups. Ninety per cent of both ventricular and supraventricular tachyarrhythmias terminated within the 13-29 beat detection interval with the Protect algorithm. The Protect group showed a significantly better event-free survival to first delivered therapy for total (P = 0.0001), appropriately treated (P = 0.002), and inappropriately treated episodes (P = 0.017). The total number of delivered shocks was significantly lower in the Protect group (22 vs. 59, P < 0.0001). In the Protect group, a significantly reduced HF hospitalization (hazard ratio 0.38, 95% CI 0.15-0.98, P = 0.044) was observed without any increase of syncope or death.


CONCLUSIONS
A simplified CRT-D device with fixed long detection reduced overall ICD therapy burden and HF hospitalizations without entailing any additional adverse events in primary prevention non-ischaemic HF patients.
Gasparini
Maurizio
M
Department of Cardiology, IRCCS Istituto Clinico Humanitas, Via Manzoni 56, Rozzano (MI) IT-2089, Italy.
Menozzi
Carlo
C
Proclemer
Alessandro
A
Landolina
Maurizio
M
Iacopino
Severio
S
Carboni
Angelo
A
Lombardo
Ernesto
E
Regoli
François
F
Biffi
Mauro
M
Burrone
Valeria
V
Denaro
Alessandra
A
Boriani
Giuseppe
G
D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects / Q000379:methods; D009202:Cardiomyopathies / Q000150:complications*; D017147:Defibrillators, Implantable; D005260:Female; D006333:Heart Failure / Q000150:complications*; D006760:Hospitalization; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017180:Tachycardia, Ventricular / Q000517:prevention & control*; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000209:etiology