This clinical trial, The cARdiac Radiation Therapy Sparing (HEARTS) trial, will compare MR-guided adaptive radiation therapy (MRgART) with substructure sparing to standard of care x-ray based linac RT with whole-heart dose metrics for patients with cancer in the thoracic region based on longitudinal changes in cardiac function using MRI, quality of life, cardiac waveforms, and blood biomarkers.
