Table 2.
CTA characteristics.
| All patients (n=1,798) |
Never smoked (n=1339, 74%) |
Former smoker (n=243, 14%) |
Current smoker (n=216, 12%) |
p-value | |
|---|---|---|---|---|---|
| Pre-scan heart rate, bpm | 57 ± 7 | 57 ± 7 | 57 ± 7 | 57 ± 6 | 0.23 |
| Tube current, mA | 539 ± 73 | 534 ± 73 | 562 ± 72 | 550 ± 74 | 0.97 |
| Tube potential, kV | 113 ± 12 | 112 ± 12 | 115 ± 12 | 113 ± 13 | 0.69 |
| Scan type | |||||
| - Prospective triggered | 1159 (64%) | 860 (64%) | 161 (66%) | 138 (64%) | 0.82 |
| - Retrospective gating | 639 (36%) | 479 (36%) | 82 (34%) | 78 (36%) | |
| CTA radiation dose, mSva | 3.9 ± 3.7 | 3.8 ± 3.6 | 4.6 ± 4.1 | 3.7 ± 3.3 | 0.15 |
| CAD severity | |||||
| - No CAD | 995 (55%) | 758 (57%) | 117 (48%) | 120 (56%) | |
| - CAD 1–49% stenosis | 604 (34%) | 438 (33%) | 95 (39%) | 72 (33%) | 0.04 |
| - CAC ≥ 50% stenosis | 139 (8%) | 97 (7%) | 26 (11%) | 20 (9%) | |
| - ≥ 1 uninterpretable segment | 60 (3%) | 46 (3%) | 5 (2%) | 4 (2%) | |
| Segment involvement score > 4 | 239 (13%) | 163 (12%) | 49 (20%) | 27 (13%) | 0.003 |
| CAC score obtained (# of patients) | 1574 (88%) | 1165 (87%) | 219 (90%) | 190 (88%) | 0.93 |
| - CAC = 0 Agatston units | 915/1574 (58%) | 699/1165 (60%) | 106/219 (48%) | 110/190 (58%) | |
| - CAC = 1–99 | 414/1574 (26%) | 296/1165 (25%) | 66/219 (30%) | 52/190 (27%) | 0.03 |
| - CAC = 100–399 | 157/1574 (10%) | 106/1165 (9%) | 34/219 (16%) | 17/190 (9%) | |
| - CAC ≥ 400 | 88/1574 (6%) | 64/1165 (5%) | 13/219 (6%) | 11/190 (6%) | |
a
Includes effective radiation for CTA only (excluding scout topogram, timing bolus and CAC scan).
CAC, coronary artery calcium; CAD, coronary artery disease; CTA, computed tomographic angiography.