BACKGROUND: Information is limited regarding the knowledge and attitudes of physicians typically involved in the referral of patients for implantable cardioverter-defibrillator (ICD) implantation. METHODS: We conducted a survey of primary care physicians and cardiologists at the University of Rochester Medical Center and the Unity Health System Rochester, NY from December 2008 to February 2009. The survey collected information regarding physicians' knowledge of and attitudes towards ICD therapy. RESULTS: Of the 332 surveys distributed, 110 (33%) were returned. Over-all 94 (87%) physicians reported referring patients for ICD implantation. Eighteen (17%) physicians reported unawareness of guidelines for ICD use. Sixty-four (59%) physicians recommended ICD in patients with ischemic cardiomyopathy and left ventricular ejection fraction (LVEF) < or = 35%. Sixty-five (62%) physicians use < or = 35% as the LVEF criterion for ICD referral in patients with non-ischemic cardiomyopathy. Cardiologists were more familiar than primary care physicians with LVEF criteria for implantation of ICD in patients with ischemic and non-ischemic cardiomyopathy (p value 0.005 and 0.002, respectively). Twenty-nine (27%) participants were unsure regarding the benefits of ICDs in eligible women and blacks. Eighty two (76%) physicians believed that an ICD could benefit patients > or = 70 years old, whereas only 53 (49%) indicated that an ICD would benefit patients > or = 80. CONCLUSIONS: A lack of familiarity with current clinical guidelines regarding ICD implantation exists. Primary care physicians are less aware of clinical guidelines than are cardiologists. This finding highlights the need to improve the dissemination of guidelines to primary care physicians in an effort to improve ICD utilization.