Is Syncope in Dilated Cardiomyopathy the Next Indication for an ICD?
Patients with nonischemic dilated cardiomyopathy (DCM) presenting with syncope have a one-year sudden death rate as high as 45%. As a result, the evaluation and treatment of these patients has been necessarily aggressive, including electrophysiologic studies (EPS), which can diagnose life-threatening ventricular arrhythmias as well as bradyarrhythmias due to sinus node dysfunction and heart block. However, as compared to patients with ischemic heart disease, EPS in patients with DCM is notoriously insensitive and may under diagnose these life-threatening conditions. Because of this, some investigators have suggested defibrillator therapy for patients with syncope, dilated cardiomyopathy and negative EPS in spite of an absence of data to support this approach. A recently published series from the University of Michigan seems to support this approach. The study, published in the Journal of the American College of Cardiology (JACC 1999;33:1964-1970), prospectively evaluated a small number
