Cardiovascular events after cancer immunotherapy as oncologic emergencies: Analyses of 610 head and neck cancer patients treated with immune checkpoint inhibitors

Background: Cardio-oncology and emergency medicine are closely collaborative, as many cardiac events in cancer patients require evaluation and treatment in the emergency department (ED). Immune checkpoint inhibitors (ICIs) have become a common treatment for patients with head and neck cancer (HNC). However, the immune-related adverse events (irAEs) from ICIs can be clinically significant. Methods: We reviewed and analyzed cardiovascular diagnoses among HNC patients who received ICI during the period April 1, 2016–December 31, 2020 in a large tertiary cancer center. Demographics, clinical and cancer-related data were abstracted, and billing databases were queried for cardiovascular disease (CVD)-related diagnosis using International Classification of Disease-version10 (ICD-10) codes. We recorded receipt of care at the ED as one of the outcome variables. Results: A total of 610 HNC patients with a median follow-up time of 12.3 months (median, interquartile range = 5–30 months) comprised our study cohort. Overall, 25.7% of patients had pre-existing CVD prior to ICI treatment. Of the remaining 453 patients without pre-existing CVD, 31.5% (n = 143) had at least one CVD-related diagnosis after ICI initiation. Tachyarrhythmias (91 new events) was the most frequent CVD-related diagnosis after ICI. The time to diagnosis of myocarditis from initiation of ICI occurred the earliest (median 2.5 months, 1.5–6.8 months), followed by myocardial infarction (3.7, 0.5–9), cardiomyopathy (4.5, 1.6–7.3), and tachyarrhythmias (4.9, 1.2–11.4). Patients with myocarditis and tachyarrhythmias mainly presented to the ED for care. Conclusion: The use of ICI in HNC is still expanding and the spectrum of delayed manifestation of ICI-induced cardiovascular toxicities is yet to be fully defined in HNC survivors.