Table 1.
Baseline Patient Characteristics (N = 233)
| Follow-up, mo | 73.7 (1.6-153.9) |
| Age at radiotherapy initiation, y | 68.1 (34.9-90.7) |
| Male | 143 (61.4) |
| Ever smoker | 189 (81.1) |
| Current smoker | 30 (12.9) |
| Diabetes | 52 (22.3) |
| Hypertension | 121 (51.9) |
| Statin use | 93 (39.9) |
| Median 10-y ASCVD risk, %a | 21.5 (0.4-71.1) |
| Concurrent chemotherapy | 228 (97.9) |
| Prior chemotherapy | 36 (15.4) |
| Postradiotherapy chemotherapy | 84 (36.1) |
| Multiple courses of thoracic radiotherapy | 38 (16.3) |
| Radiotherapy technique | |
| VMAT | 174 (74.7) |
| IMRT | 58 (24.9) |
| 3D CRT | 1 (0.4) |
| Prior cardiac events | 71 (30.5) |
| Multiple prior cardiac events | 35 (15.0) |
| Grade ≥3 cardiac events following radiotherapy | 52 (22.3) |
| Myocardial | 19 (36.5) |
| Constrictive | 3 (5.8) |
| Valvular | 3 (5.8) |
| Conduction | 27 (51.9) |
| Time to first postradiotherapy cardiac event, mo | 21.5 (1.7-118.9) |
| Cohort heart dosimetry | |
| Mean heart dose, Gy | 9.3 (IQR: 2.5-12.9) |
| Mean TotalLeft V15, % | 21.6 (IQR: 0.0-37.8) |
| Mean TotalLeft V15, cc | 1.2 (IQR: 0.0-2.1) |
| CAC score distribution | |
| None | 52 (22.3) |
| Mild | 62 (26.6) |
| Moderate | 58 (24.9) |
| Severe | 61 (26.2) |
Values are median (range) or n (%) except as indicated.
Chemotherapy regimens listed in Supplemental Table 3.
3D = 3-dimensional; ASCVD = atherosclerotic cardiovascular disease; CAC = coronary artery calcium; CRT = conformal radiotherapy; IMRT = intensity-modulated radiotherapy; TotalLeft = combined 3-vessel arteries; V15 = volume receiving 15 Gy; VMAT = volumetric modulated arc therapy.
a
Clinical and laboratory information was sufficient to calculate ASCVD score for 18.9% of the total cohort (n = 44).