Abstract
BACKGROUND: The American College of Cardiology, the American Heart Association, and the Heart Rhythm Society guidelines provide patient selection criteria for primary prevention implantable cardioverter-defibrillators (ICDs). For unknown reasons, guideline-discordant practice is common. OBJECTIVE: To determine referring physicians' concordance with the primary prevention ICD guidelines. METHODS: We mailed a survey regarding ICD guidelines and individual practice characteristics to a random national sample of 3000 physicians selected from the American Medical Association Masterfile-one-third each specializing in family medicine, internal medicine, and general cardiology. RESULTS: Sixty-four percent with correct contact information responded. Three hundred ninety-five (28%; 95% confidence interval [CI] 25%-30%) respondents never refer patients with the intent of consideration for a primary prevention ICD, including 7% (95% CI 5%-10%) of cardiologists. Two hundred twelve (15%; 95% CI 13%-17%) believe ventricular arrhythmias are required before a primary prevention ICD is indicated; 525 (36%; 95% CI 34%-39%) believe that an ejection fraction of >40% warrants a primary prevention ICD; and 361 (25%; 95% CI 23%-27%) would refer a patient for a primary prevention ICD within 40 days of a myocardial infarction. In multivariate analyses, family practice physicians and physicians residing in the western United States most often provided guideline-discordant answers, while cardiologists and those who refer to an electrophysiologist most often provided guideline-concordant answers. Primary care physicians who manage heart failure patients without referral to a subspecialist were not more likely to provide guideline-concordant answers. CONCLUSIONS: Answers discordant with the primary prevention ICD guidelines were common, suggesting that referring physician beliefs are an important barrier to appropriate patient referrals for primary prevention ICD implantation.