Radiation-induced cardiac disease: Modern techniques to reduce cardiac toxicity.

Purpose: Continuous advancements in cancer management have resulted in increased long-term survival rates amongst cancer survivors and in turn have exposed the full extent of radiotherapy-associated morbidities. Radiation-induced coronary heart disease (RICHD) is one of the leading causes of morbidity and mortality in cancer survivors, particularly in those having undergone mediastinal radiation. While mediastinal radiation has been shown to substantially reduce both recurrence and mortality rates in multiple thoracic malignancies, the risk for the development of RICHD is of significant concern. Not only is the pathophysiology of RICHD yet to be fully elucidated but therapeutic options are lacking.

Methods and materials: Literature was reviewed with a focus on RICHD in Hodgkin's Lymphoma, breast and lung cancer patients, and the current modern radiotherapeutic techniques used to minimize radiation exposure of the heart.

Results: Multiple approaches have been taken to minimize exposure of the heart to ionizing radiation in cancers that require mediastinal radiation, most notably Hodgkin's Lymphoma, breast and lung cancer. RICHD Protection strategies include optimized delineation protocols, utilization of the moderate deep inspiration breath hold (mDIBH), specialized mDIBH monitoring, continuous positive airway pressure and various other cardiac sparing techniques. A combination of medical prevention and therapy with physical protective approaches may be vital in achieving significant cardio-protection.

Conclusion: Despite continuous advances and improvements in protective strategies, mainly by physically distancing the heart from radiation targets to minimize exposure and by sophisticated radiation dose planning, RICHD remains a significant challenge in cancer treatment rehabilitation and survivorship.