Immunotherapy-associated complete heart block in a patient with NSCLC: A case report and literature review.

The role for PD-1/PD-L1 and CTLA-4 targeted immunotherapy is well outlined in the treatment of metastatic NSCLC. Increased survival benefit supports the use of these medications and the development of next-generation agents with improved efficacy and favorable side-effect profiles. The prevalence of immunotherapy-associated cardiotoxicity (IAC) has grown significantly over the past two years as awareness of this toxicity class has emerged. High-grade conduction disorders comprise a subset of cardiotoxicities with a high case fatality rate. We presented a case of suspected combination ipilimumab-nivolumab associated 3rd degree heart block. The onset of this event was 16 days after immunotherapy initiation. A literature review has suggested that over 75% of cases of cardiotoxicity are observed within the first 6 weeks. We present findings from an interrogation of the FDA Adverse Event Reporting System (FAERS) and provide clinical guidance for the early identification of high-risk patients.