Radiation-induced cardiomyopathy as a function of radiation beam gating to the cardiac cycle.
Portions of the heart are often unavoidably included in the primary treatment volume during thoracic radiotherapy, and radiation-induced heart disease has been observed as a treatment-related complication. Such complications have been observed in humans following radiation therapy for Hodgkin's disease and treatment of the left breast for carcinoma. Recent attempts have been made to prevent re-stenosis following angioplasty procedures using external beam irradiation. These attempts were not successful, however, due to the large volume of heart included in the treatment field and subsequent cardiac morbidity. We suggest a mechanism for sparing the heart from radiation damage by synchronizing the radiation beam with the cardiac cycle and delivering radiation only when the heart is in a relatively hypoxic state. We present data from a rat model testing this hypothesis and show that radiation damage to the heart can be altered by synchronizing the radiation beam with the cardiac cycle. This technique may be useful in reducing radiation damage to the heart secondary to treatment for diseases such as Hodgkin's disease and breast cancer.
Gladstone
David J
DJ
Division of Radiation Oncology, Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA. David.Gladstone@dartmouth.edu
Flanagan
Michael F
MF
Southworth
Jean B
JB
Hadley
Vaughn
V
Thibualt
Melissa Wei
MW
Hug
Eugen B
EB
Hoopes
P Jack
PJ
D017130:Angioplasty; D000818:Animals; D001943:Breast Neoplasms / Q000532:radiotherapy; D002277:Carcinoma / Q000532:radiotherapy; D009202:Cardiomyopathies / Q000209:etiology*; D003251:Constriction, Pathologic / Q000517:prevention & control; D004562:Electrocardiography; D006321:Heart / Q000528:radiation effects*; D006689:Hodgkin Disease / Q000532:radiotherapy; D006801:Humans; D009206:Myocardium / Q000473:pathology; D010315:Particle Accelerators; D011832:Radiation Injuries / Q000517:prevention & control*; D011874:Radiometry; D011878:Radiotherapy / Q000009:adverse effects* / Q000379:methods*; D011880:Radiotherapy Planning, Computer-Assisted; D051381:Rats; D013997:Time Factors