Be a good LAD.

Have we learned anything since Darby demonstrated that infamous 7.4% relative increase in major cardiac events with each 1 Gy-increase in mean heart dose? Brought to us, by the way, by data on women receiving breast radiation in the 60s-90s when the average mean heart dose was roughly 5 Gy. Here’s data on 701 patients receiving thoracic (not breast!) radiation between 2003-2014 at Harvard-affiliated sites demonstrating that, if the volume of left anterior descending (LAD) coronary artery receiving at least 15 Gy is ≥ 10%, there is a clear increase in major cardiac events. In fact, among patients without baseline coronary heart disease, such dosimetry was associated with a detriment in overall survival at 10 years (42% versus 51% without bad LAD dosimetry). | Atkins, JAMA Oncol 2021