Exploring Variances in Dual-Chamber ICD Use

Each year in the United States, approximately 140,000 implantable cardioverter-defibrillators (ICDs) are implanted in cardiac patients. Physicians often face challenges when working with patients to decide whether it’s best to use a single- or dual-chamber device. Some patients have a clear indication for a dual-chamber device because they have an indication for a pacemaker. For patients without an indication for a pacemaker, the decision is much less clear. The potential benefits of dual-chamber devices remain to be proven, and they may have more complications. Clinical trial data to guide physicians on which option to choose have been lacking. Currently, nearly two-thirds of patients undergoing ICD implantation for primary prevention receive dual-chamber devices. Variations in Dual-Chamber ICD Use In a study published in the April 23, 2012 Archives of Internal Medicine, my colleagues and I set out to explore hospital-level variation in the use of dual-chamber ICDs across the U.S. Using the Medicare-mandated National Cardiovascular Data Registry (NCDR) ICD registry, we looked at 87,115 patients from 2006 to 2009 receiving an ICD as primary prevention without a documented indication for a pacemaker. We only wanted to analyze patients for whom it wasn’t clear whether a single- or dual-chamber ICD was the appropriate choice. Of these patients, about 58% received a dual-chamber ICD. More importantly, use of each ICD type varied significantly by hospital and by physician. In some hospitals and with some physicians, 100% of patients without a clear indication for a dual-chamber ICD received such a device. At other hospitals and with other physicians, 0% of these patients received a dual-chamber ICD. “Differences in the local culture and practice...