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A Network Analysis of Variation in Evidence-based ICD Implantation

*A. James O'Malley, Geisel School of Medicine at Dartmouth College 


Despite implantable cardioverter defibrillators (ICDs) being proven effective for the prevention of sudden cardiac death in patients with advanced systolic heart failure, research confirms variation of use of ICDs. In this work, we examined the variation in patient selection for ICD implantation from a network science perspective using network measures that represent aspects of care coordination. We analyzed data from Medicare claims for patients diagnosed with congestive heart failure to construct within and between hospital networks of physicians. We used the National Cardiovascular Data Registry’s ICD Registry, a national registry of ICD implantations, to calculate variation in evidence-based ICD implantation rates. We performed a case study of two geographically adjacent hospital referral regions (HRRs) that have similar rates of ICD use, but differ in their adherence to the ICD guidelines. We hypothesized that the network positions of physicians who implant ICDs may be different for hospitals that adhere to the ICD guidelines compared with hospitals that do not. We used visualization methods and statistical analysis to investigate this hypothesis.