Abstract Background Immune checkpoint inhibitors (ICI) have revolutionized the treatment of various malignancies, but pose potential cardiotoxic risks, particularly in high-risk patients with pre-existing cardiovascular disease or prior cardiotoxic chemotherapy. Methods A retrospective analysis was conducted on a Cardio-Oncology clinic (july 2018 - december 2024). Cardiotoxicity was defined as asymptomatic troponin/BNP elevation, new rhythm disturbances, new left ventricular dysfunction or myocarditis. Patients with pre-existing cardiovascular disease or prior cardiotoxic chemotherapy were classified as high risk. Results A total of 53 patients (median age: 66 years; 60% male) were included. Cardiovascular risk factors included hypertension (51%), dyslipidemia (51%), diabetes (19%), smoking history (40%) and overweight status (11%). Pre-existing cardiac conditions were present in 40% of patients, including coronary artery disease (11%), atrial fibrillation (9%) and heart failure (6%). Baseline medications included ACE inhibitors (21%), beta-blockers (36%) and statins (49%). Median left ventricular ejection fraction was 59%. Baseline high-sensitivity troponin levels were typically 1.9 ng/L and median BNP level was 158 pg/mL. The most frequently used ICI were pembrolizumab (59%) and nivolumab (25%). The most common malignancies were skin (25%), breast and kidney cancers (11% each), with other cancers including lung, stomach, urothelial, esophageal, thyroid, and endometrial malignancies. High cardiotoxicity risk was identified in 59% of patients, with 38% having prior exposure to cardiotoxic chemotherapy. Median treatment duration was 154 days. Over a median follow-up period of nine months, 13% of patients developed cardiotoxicity: troponin elevation (6%), BNP elevation requiring diuretics (2%), new-onset atrial fibrillation (2%) and myocarditis requiring hospitalization (4%). Cardio-protective therapy was initiated in 26% of patients, either preemptively (17%) or after cardiotoxicity (9%), Two patients developed myocarditis – one on pembrolizumab for breast cancer and another on nivolumab for kidney cancer. Both were hospitalized and managed with high-dose corticosteroids; one required additional immunosuppressive therapy. Both patients recovered but did not resume immunotherapy. Overall, 43% of patients died during the follow-up period, although no deaths were attributed to cardiac causes. The median survival time from cancer diagnosis was 27 months. Conclusion While ICI are highly effective in treating malignancies, their cardiotoxicity potencial requires vigilant monitoring, particularly in high-risk patients. Though rare, ICI-associated myocarditis should be considered in patients with new-onset cardiac symptoms and elevated troponin, even in the absence of left ventricular dysfunction. Future research will bring new perspectives on risk stratification, optimal monitoring and safe immunotherapy resumption.
Gonçalves et al. (Fri,) studied this question.