751 CANCER TREATMENT RELATED COMPLICATIONS IN PATIENTS WITH HYPERTROPHIC CARDIOMYOPATHY

Introduction Cardiotoxicity involves direct effects of cancer related treatment on heart function, commonly presenting as left ventricular contractile dysfunction. However, limited data are available regarding cardiotoxicity on hypertrophic cardiomyopathy (HCM), because most studies and registries have not specifically analyzed the effects of oncological treatment in HCM populations. This gap in knowledge may lead to unjustified restriction of HCM patients to radical cancer treatments. Aim We aimed at describing the potential clinical cardiotoxicity of oncological treatments in a cohort of consecutive HCM patients, systematically followed up at two national referral centres for HCM. Methods We retrospectively analysed all clinical and instrumental data of all consecutive HCM patients who underwent oncological treatment between January 2000 and December 2020, collected in a centralized database. Results Of 3256 HCM patients, 121 (3.7%) had a reported diagnosis of cancer; 109 (90.1%) patients underwent oncological surgery, 45 (37.2%) chemotherapic treatment, 22 (18.2%) chest radiotherapy. After a median follow up of 5 (2-13) years from oncological diagnosis, 32 of the 121 patients (26.4%) died. The cause of death was mainly attributed to the oncological condition, while 4 (12.5%) patients died of sudden cardiac death without previous chemotherapy or chest radiotherapy. No patient interrupted or reduced the dose of oncological treatment due to cardiac dysfunction. No sustained ventricular tachyarrhythmia was induced by chemotherapy or radiotherapy. Conclusions Cancer treatment is well tolerated in HCM patients. In our oncology series, none died of cardiovascular complications induced by chemotherapy or chest radiotherapy and none required interruption or substantial tapering of treatment due to cardiovascular side effects. Although expert multidisciplinary evaluation is mandatory and regimens must be tailored individually, the diagnosis of HCM per se should not be considered a contraindication to radical cancer treatment.