| Title: |
Abstract 4357269: Dose-Dependent Effects of Radiation on the Coronary Arteries: Results from Proton Beam Cardiac Radioablation in Swine |
| Authors: |
Hirao, Tatsuhiko; Rettmann, Maryam; Deisher, Amanda; Koya, Taro; Gades, Naomi; Kruse, Jon; Merrell, Kenneth; Shumway, Dean; Packer, Douglas; Siontis, Konstantinos |
| Source: |
Circulation ; volume 152, issue Suppl_3 ; ISSN 0009-7322 1524-4539 |
| Publisher Information: |
Ovid Technologies (Wolters Kluwer Health) |
| Publication Year: |
2025 |
| Description: |
Background: Cardiac radioablation (CRA) is emerging as a treatment modality for refractory ventricular tachycardia (VT). This study aimed to evaluate the effects of radiation on the coronary arteries in a swine model of proton beam CRA. Methods: Eighteen domestic swine underwent 30–40 Gy pencil-beam scanning proton therapy in a single-fraction targeting the left ventricle with no attempt to spare coronary arteries and were euthanized 12-40 weeks later. Contrast-enhanced cardiac computed tomography (CT) was performed at baseline for treatment planning and at study end. Using dose-volume histograms, the maximum point (D max ), mean (D mean ) doses and the minimal doses received by the highest irradiated volumes of 0.01 cc (D 0.01cc ) for the left main, left anterior descending, circumflex, and right coronary artery, as well as the large diagonal and obtuse marginal branches were calculated. The D max location for each artery was mapped from the baseline planning CT onto the follow-up CT using deformable registration. Coronary artery segments were harvested from the D max sites for histological analysis. Receiver operating characteristic (ROC) analysis was performed to identify dose thresholds for predicting histologically severe coronary stenoses (≥75%). Results: Ninety-six coronary artery segments were analyzed. No stenoses were observed by CT imaging before irradiation. By histological analysis post-euthanasia, 25/96 (26%) coronary segments sampled at the Dmax site per artery had ≥75% stenosis. The median D max was 4.7 Gy for the |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| DOI: |
10.1161/circ.152.suppl_3.4357269 |
| Availability: |
https://doi.org/10.1161/circ.152.suppl_3.4357269 |
| Accession Number: |
edsbas.D7F79061 |
| Database: |
BASE |