Chapter 1 - Cardiac Complications of Cancer and Anti-Cancer Treatment
Chest radiation, used to treat lymphoma, breast and lung cancers, is associated with an increased risk of late cardiovascular effects through two mechanisms: microvascular disruption leading to cellular death and fibrosis, and accelerated macrovascular atherosclerosis. These affect not only the myocardium but also the pericardium, coronary arteries, and the heart valvular and conduction systems.
The risk of cardiac disease depends mostly on the radiation dose (dose >30 Gy), volume of the heart exposed (improvements in radiation techniques seem to reduce it) and radiation delivery techniques (dose per fraction >2 Gy). However, other risk factors include age (younger patients are at higher risk), longer time since exposure (incidence of heart disease continues to increase even 30 years after radiation), gender, exposure to other cardiotoxic treatments, or other CV risk factors.
High-risk patients, such as those who received a mediastinal/heart dose of >30 Gy as children or young adults, should be followed up closely.