In this retrospective study of 375 left side breast cancer patients receiving radiation, increasing left anterior descending (LAD) coronary artery mean dose, LAD max dose, and heart mean dose were associated with an increased risk of major cardiac events after treatment. The overall rate of any cardiac event was 9.6%, and the rate of major cardiac events was 6.1%. They derived very conservative dose thresholds for increased cardiac risk including a LAD mean (when using moderate hypofractionation) of 4.9 Gy, a LAD max of 10.2 Gy, and a mean heart dose of 1.5 Gy. | Zureick, Int J Radiat Oncol Biol Phys 2022
