Clinical outcome in patients with implantable cardioverter-defibrillator and cancer: a nationwide study.

ABSTRACT

AIMS: Patients with cancer are insufficiently represented in randomized clinical trials investigating efficacy of implantable cardioverter-defibrillators (ICDs). We aimed to describe outcomes in patients with a pre-existing diagnosis of cancer at time of ICD implantation. METHODS AND RESULTS: We utilized Danish nationwide registries to identify primary and secondary prevention ICD implantations from 2007 to 2012. Multivariable Cox models were used to assess the risk of appropriate ICD therapy and mortality in patients with and without cancer at time of implantation. During a median follow-up of 2.1 years, 2935 primary prevention ICD and 2730 secondary prevention ICD implantations were identified. Out of these [289 (5.1%)] had pre-existing cancer [primary 140 (4.8%), secondary 149 (5.5%)]. No differential risk for appropriate ICD therapy was found between patients with or without cancer, [primary cancer 19/140, no cancer 380/2795, hazard ratio (HR) = 1.07 (0.67-1.69)] and [secondary cancer 42/149, no cancer 699/2581, HR = 1.28 (0.93-1.75)]. In primary patients, cancer was not associated with higher risk of 1-year [cancer 10/140, no cancer 133/2795, HR = 1.20 (0.84-2.28)] or all-time mortality [cancer 22/140, no cancer 339/2795, HR = 1.13 (0.74-1.75)]. In secondary patients, cancer was associated with a higher 1-year [cancer 19/149, no cancer 108/2581, HR = 2.62 (1.60-4.29)] and all-time mortality [cancer 44/149, no cancer 315/2581, HR = 2.36 (1.71-3.24)]. CONCLUSION: Implantable cardioverter-defibrillators were implanted in a minority of cancer patients. No difference in risk of appropriate therapy was observed between cancer and non-cancer patients, regardless of implant indication. Cancer was associated with increased mortality in secondary prevention ICD patients, but not in primary prevention ICD patients. In secondary prevention ICD patients, the majority of deaths were attributable to cancer.