Chest Radiotherapy Associated Cardiotoxicity: An Update

Chest radiotherapy has improved cancer survival in various thoracic malignancies, including breast cancer, Hodgkin lymphoma, and lung cancer. However, inadvertent radiation exposure to the heart is associated with a broad spectrum of cardiovascular toxicities, collectively termed radiation-induced heart disease (RIHD). We aim to review the pathophysiology of RIHD and the current evidence for their incidence, risk factors, clinical management, and prevention strategies.

RIHD is mediated by oxidative stress, DNA damage, endothelial dysfunction, inflammation, and progressive fibrosis, leading to accelerated atherosclerosis, myocardial stiffening, valvular degeneration, pericardial disease, and arrhythmias. The risk, timing, and severity of cardiovascular complications are influenced by radiation dose and distribution, age at exposure, baseline cardiovascular risk, and concomitant cardiotoxic therapies. While younger patients may experience prolonged latency before clinical disease onset, older individuals and those with pre-existing cardiovascular disease often develop complications earlier, reflecting radiation-mediated acceleration of underlying pathology. This review summarizes the epidemiology, latency, clinical presentation, surveillance strategies, and management of the different forms of RIHD. It also discusses contemporary approaches to risk mitigation, including advances in radiation delivery techniques, aggressive cardiovascular risk factor modification, lifestyle interventions, and emerging pharmacologic strategies.