An overview of radiation-induced heart disease

Abstract

Radiation therapy (RT) has dramatically improved cancer survival, leading to several inevitable complications. Unintentional irradiation of the heart can lead to radiation-induced heart disease (RIHD), including cardiomyopathy, pericarditis, coronary artery disease, valvular heart disease, and conduction system abnormalities. Furthermore, the development of RIHD is aggravated with the addition of chemotherapy. The screening, diagnosis, and follow-up for RIHD in patients who have undergone RT are described by the consensus guidelines from the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE). There is compelling evidence that chest RT can increase the risk of heart disease. Although the prevalence and severity of RIHD are likely to be reduced with modern RT techniques, the incidence of RIHD is expected to rise in cancer survivors who have been treated with old RT regimens. However, there remains a gap between guidelines and clinical practice. Currently, therapeutic modalities followed in the treatment of RIHD are similar to the non-irradiated population. Preventive measures mainly reduce the radiation dose and radiation volume of the heart. There is no concrete evidence to endorse the preventive role of statins, angiotensin-converting enzyme inhibitors, and antioxidants. This review summarizes the current evidence of RIHD subtypes and risk factors and suggests screening regimens, diagnosis, treatment, and preventive approaches.

Keywords: Antioxidants; Cardiomyopathies; Coronary artery disease; Inflammation; Oxidative stress; Radiation-induced abnormalities; Radiotherapy.

Fig. 1.

Schematic diagram illustrating the risk factors for radiation-induced heart disease (RIHD).

Fig. 2.

Algorithmic demonstrations of screening guidelines of radiation-induced heart disease (RIHD). Adapted from the European Association of Cardiovascular Imaging (EACVI) and American Society of Echocardiography (ASE) guidelines, 2013. CMR, cardiac magnetic resonance; CT, computed tomography; CVS, cardiovascular system; DM, diabetes mellitus; HLD, hyperlipidemia; HTN, hypertension; PND, paroxysmal nocturnal dyspnea.

Fig. 3.

The clinical spectrum and recommended management strategies of radiation-induced heart diseases. ACE, angiotensin converting enzyme.