Anthracycline-induced cardiovascular toxicity: validation of the Heart Failure Association and International Cardio-Oncology Society risk score

Abstract Background and Aims Baseline cardiovascular toxicity risk stratification is critical in cardio-oncology. The Heart Failure Association (HFA) and International Cardio-Oncology Society (ICOS) score aims to assess this risk but lacks real-life validation. This study validates the HFA-ICOS score for anthracycline-induced cardiovascular toxicity. Methods Anthracycline-treated patients in the CARDIOTOX registry (NCT02039622) were stratified by the HFA-ICOS score. The primary endpoint was symptomatic or moderate to severe asymptomatic cancer therapy-related cardiac dysfunction (CTRCD), with all-cause mortality and cardiovascular mortality as secondary endpoints. Results The analysis included 1066 patients (mean age 54 ± 14 years; 81.9% women; 24.5% ≥65 years). According to the HFA-ICOS criteria, 571 patients (53.6%) were classified as low risk, 333 (31.2%) as moderate risk, 152 (14.3%) as high risk, and 10 (0.9%) as very high risk. Median follow-up was 54.8 months (interquartile range 24.6–81.8). A total of 197 patients (18.4%) died, and 718 (67.3%) developed CTRCD (symptomatic: n = 45; moderate to severe asymptomatic: n = 24; and mild asymptomatic: n = 649). Incidence rates of symptomatic or moderate to severe symptomatic CTRCD and all-cause mortality significantly increased with HFA-ICOS score [hazard ratio 28.74, 95% confidence interval (CI) 9.33–88.5; P < .001, and hazard ratio 7.43, 95% CI 3.21–17.2; P < .001) for very high-risk patients. The predictive model demonstrated good calibration (Brier score 0.04, 95% CI 0.03–0.05) and discrimination (area under the curve 0.78, 95% CI 0.70–0.82; Uno’s C-statistic 0.78, 95% CI 0.71–0.84) for predicting symptomatic or severe/moderate asymptomatic CTRCD at 12 months. Conclusions The HFA-ICOS score effectively categorizes patients by cardiovascular toxicity risk and demonstrates strong predictive ability for high-risk anthracycline-related cardiovascular toxicity and all-cause mortality.