Low Referral Pattern for Implantable Defibrillator Therapy in a Tertiary Hospital: Referral Physician Survey and Monte Carlo Simulation

Although implantable cardioverter defibrillator (ICD) therapy is the standard of care for prevention of sudden cardiac death (SCD), its underutilization is a clinical concern. We performed a retrospective study on patients who underwent cardiac catheterization at a tertiary medical center to identify those who were eligible for ICD therapy as per the guidelines and those who actually received it as a part of treatment. Surprisingly, only 4.4% of eligible patients received ICD for SCD prevention. Assuming that the major cause of this underutilization of ICD therapy was low referral, we performed a structured survey among the referring physicians to assess specialists' availability, primary care physicians' role in ICD referral, patient management concerns, familiarity with ICD guidelines, and economics of ICD implantation. Physician response rate of the survey was 51% (35/68). Survey results showed that the common reasons for underreferral included nonavailability of electrophysiologists (34%), poor quality of life of patients (25.7%), patients not being on optimal therapy (25.7%), and low awareness (22.85%). Subsequently, a Monte Carlo simulation was used to assess a hypothetical survival of the study cohort, which showed that in an "ideal scenario" of ICD implantation, the mortality in the study cohort was decreased by 6.9% and 12.3% at 2- and 5-year follow-up, respectively. This study highlights the underutilization of ICDs and the referring physicians' approach to this therapy.