Prophylactic defibrillator implantation in patients with nonischemic dilated cardiomyopathy.
BACKGROUND
Patients with nonischemic dilated cardiomyopathy are at substantial risk for sudden death from cardiac causes. However, the value of prophylactic implantation of an implantable cardioverter-defibrillator (ICD) to prevent sudden death in such patients is unknown.


METHODS
We enrolled 458 patients with nonischemic dilated cardiomyopathy, a left ventricular ejection fraction of less than 36 percent, and premature ventricular complexes or nonsustained ventricular tachycardia. A total of 229 patients were randomly assigned to receive standard medical therapy, and 229 to receive standard medical therapy plus a single-chamber ICD.


RESULTS
Patients were followed for a mean (+/-SD) of 29.0+/-14.4 months. The mean left ventricular ejection fraction was 21 percent. The vast majority of patients were treated with angiotensin-converting-enzyme (ACE) inhibitors (86 percent) and beta-blockers (85 percent). There were 68 deaths: 28 in the ICD group, as compared with 40 in the standard-therapy group (hazard ratio, 0.65; 95 percent confidence interval, 0.40 to 1.06; P=0.08). The mortality rate at two years was 14.1 percent in the standard-therapy group (annual mortality rate, 7 percent) and 7.9 percent in the ICD group. There were 17 sudden deaths from arrhythmia: 3 in the ICD group, as compared with 14 in the standard-therapy group (hazard ratio, 0.20; 95 percent confidence interval, 0.06 to 0.71; P=0.006).


CONCLUSIONS
In patients with severe, nonischemic dilated cardiomyopathy who were treated with ACE inhibitors and beta-blockers, the implantation of a cardioverter-defibrillator significantly reduced the risk of sudden death from arrhythmia and was associated with a nonsignificant reduction in the risk of death from any cause.
Kadish
Alan
A
Clinical Cardiology Trials Office, Division of Cardiology, Department of Medicine, Northwestern University Medical School, Chicago, USA. a-kadish@northwestern.edu
Dyer
Alan
A
Daubert
James P
JP
Quigg
Rebecca
R
Estes
N A Mark
NA
Anderson
Kelley P
KP
Calkins
Hugh
H
Hoch
David
D
Goldberger
Jeffrey
J
Shalaby
Alaa
A
Sanders
William E
WE
Schaechter
Andi
A
Levine
Joseph H
JH
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000401:mortality; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000188:drug therapy / Q000401:mortality / Q000628:therapy*; D003131:Combined Modality Therapy; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control; D017147:Defibrillators, Implantable; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000628:therapy
D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors