Should stimulation therapy for congestive heart failure be combined with defibrillation backup?
Biventricular pacing has been proposed to resynchronize ventricular contraction in patients with congestive heart failure (CHF) and interventricular conduction delay. However, the sudden death rate is still high despite the improvement in cardiac performance. Devices combining biventricular pacing with implantable cardioverter defibrillator (ICD) backup are now under clinical investigation to demonstrate whether they can decrease sudden death. From the first implant of an ICD with biventricular transvenous pacing on August 1998 to April 2000, 96 patients underwent such implants: 67 (70%) received pacemakers alone and 29 (30%), who had class I ICD indications, received combined pacemaker/ICD systems. During a mean follow-up of 283 +/- 170 days, 13 (14%) patients died: 5 of 29 (17%) in the ICD group and 8 of 67 (12%) in the pacemaker group. A total of 15 patients (52%) had ICD shocks and 6 patients (21%) had 113 episodes of ventricular tachyarrhythmias, of which 96 (85%) were converted to sinus rhythm with antitachypacing. The echocardiograms showed a narrowing of the delay between the onset of right and left ventricular outflow from 40 +/- 37 msec to 17 +/- 16 msec (p = 0.03) and a reduction of the mitral regurgitation area from 7 +/- 3.8 cm2 to 5 +/- 4 cm2 (p = 0.04) at 3 months. Functional class improved from 2.8 +/- 0.7 to 1.6 +/- 0.5 (p <0.001) 3 months after implant. Thus, ischemic patients with reduced left ventricular ejection fraction and ventricular tachyarrhythmias seem good candidates for biventricular pacing with ICD backup. The sudden death risk for those with idiopathic dilated cardiomyopathy, however, is difficult to stratify, and the choice of ICD backup has to be considered on the basis of patient safety, as well as of costs.
Gaita
F
F
Division of Cardiology, Ospedale Civile of Asti, Asti, Italy.
Bocchiardo
M
M
Porciani
M C
MC
Vivalda
L
L
Colella
A
A
Di Donna
P
P
Caponi
D
D
Bruzzone
M
M
Padeletti
L
L
D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000295:instrumentation*; D005260:Female; D006333:Heart Failure / Q000150:complications*; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial