Table 4 Heart rate parameters, CCT scan parameters, and image quality in the low-dose landiolol group and the high-dose landiolol group among patients with baseline HR ≥75/min
Low-dose landiolol | High-dose landiolol | P value | |
|---|---|---|---|
(n = 77) | (n = 92) | ||
HR before β-blocker, min-1 | 80.3 ± 4.3 | 79.7 ± 4.1 | 0.42 |
Average HR during the main scan, min-1 | 69.0 ± 6.9 | 67.2 ± 6.9 | 0.10 |
Range of HR during the main scan, min-1 | 5.3 ± 12.2 | 5.9 ± 14.9 | 0.77 |
Decrease at HR, min-1 | 11.2 ± 6.0 | 12.5 ± 6.1 | 0.18 |
Time between β-blocker administration and main scan, min | 4.1 ± 0.66 | 3.7 ± 0.80 | < 0.001 |
Helical pitch | 0.69 | ||
Step and shoot | 0 (0.0%) | 0 (0.0%) | |
0.16 | 72 (93.5%) | 86 (93.5%) | |
0.18 | 3 (3.9%) | 5 (5.4%) | |
0.2 | 0 (0.0%) | 0 (0.0%) | |
0.22 | 0 (0.0%) | 0 (0.0%) | |
0.24 | 2 (2.6%) | 1 (1.1%) | |
No. of sectors used | 0.27 | ||
1 | 10 (13.0%) | 6 (6.5%) | |
2 | 59 (76.6%) | 79 (85.9%) | |
3 | 8 (10.4%) | 7 (7.6%) | |
Total exposure, DLP | 1582 ± 212 | 1594 ± 232 | 0.74 |
Main scan duration, sec | 7.2 ± 0.63 | 7.5 ± 0.97 | 0.01 |
Premature beats during the main scan | 6 (7.8%) | 6 (6.5%) | 0.75 |
Failure at breathholding | 1 (1.3%) | 2 (2.2%) | 0.67 |
Presence of coronary artery plaque | 32 (41.6%) | 51 (55.4%) | 0.07 |
Presence of calcification | 53 (68.3%) | 73 (79.4%) | 0.12 |
Maximum image quality score per patient | 0.02 | ||
1 | 15 (19.5%) | 21 (22.8%) | |
2 | 14 (18.2%) | 28 (30.4%) | |
3 | 16 (20.8%) | 23 (25.0%) | |
4 | 17 (22.1%) | 13 (14.1%) | |
5 | 15 (19.5%) | 7 (7.6%) | |
Image quality score per vessel | |||
RCA | 0.005 | ||
1 | 19 (24.7%) | 30 (32.6%) | |
2 | 11 (14.3%) | 26 (28.3%) | |
3 | 16 (20.8%) | 20 (21.7%) | |
4 | 21 (27.3%) | 10 (10.9%) | |
5 | 10 (13.0%) | 6 (6.5%) | |
LAD | 0.054 | ||
1 | 29 (37.7%) | 39 (42.4%) | |
2 | 13 (16.9%) | 32 (34.8%) | |
3 | 19 (24.7%) | 11 (12.0%) | |
4 | 13 (16.9%) | 8 (8.7%) | |
5 | 3 (3.9%) | 2 (2.2%) | |
LCX | 0.02 | ||
1 | 29 (37.7%) | 44 (47.8%) | |
2 | 12 (15.6%) | 20 (21.7%) | |
3 | 10 (13.0%) | 17 (18.5%) | |
4 | 19 (24.7%) | 8 (8.7%) | |
5 | 7 (9.1%) | 3 (3.3%) |