A greater burden of atrial fibrillation is associated with a higher risk of ischemic stroke independent of known stroke risk factors in adults with paroxysmal atrial fibrillation.

Background--The purpose of this study is to describe key elements, clinical outcomes, and potential uses of the Kaiser Permanente-Cardiac Device Registry.

Background Implantable cardioverter defibrillators (ICDs) are increasingly used for primary prevention followingrandomized controlled trials (RCTs) demonstrating that they reduce the risk of death in patients with left ventricular systolic dysfunction (LVSD). The extent to which the clinical characteristics and long-term outcomes of unselected, community-based patients with LVSD undergoing primary prevention ICD implantation in a real-world setting compare with those enrolled in the RCTs is not well characterized. The Longitudinal Study of ICDs is being conducted to address these questions. Methods and Results The study cohort includes consecutive patients undergoing primary prevention ICD placement between 1/1/2006 and 12/31/2009 in seven health plans. Baseline clinical characteristics were acquired from the NCDRICD Registry. Longitudinal data collection is underway and will include hospitalization, mortality, and resource utilization from the Virtual Data Warehouse. Data regarding ICD therapies will be obtained through chart abstraction and adjudicated by a panel of experts in device therapy. Compared with the populations of primary prevention ICD therapy RCTs, the cohort (n=2,621) is on average significantly older (by 2.5-6.5 years); more often female, more often from racial and ethnic minority groups, and has a significantly higher burden of coexisting conditions. The cohort is similar, however, to a national population undergoing primary prevention ICD placement. Conclusions Patients undergoing primary prevention ICD implantation in the Longitudinal Study of ICDs differ from those enrolled in the RCTs that established the efficacy of ICDs. Understanding a broad range of health outcomes, including ICD therapies, in this cohort will provide patients, clinicians, and policy-makers with contemporary data to inform decision-making.