Table 3.
Comparison of variables according to the number of stent retriever passes.
| First-pass recanalization (n = 68) | 2- or 3-Pass recanalization (n = 43) | ≥4-Pass recanalization (n = 25) | No recanalization (n = 29) | Pa | P for trendb | |
|---|---|---|---|---|---|---|
| Age, years | 69.4 ± 11.5 | 71.7 ± 9.4 | 68.2 ± 10.5 | 72.0 ± 13.3 | 0.449 | 0.588 |
| Sex, men | 31 (45.6) | 23 (53.5) | 15 (60.0) | 13 (44.8) | 0.564 | 0.724 |
| Hypertension | 45 (66.2) | 32 (74.4) | 18 (72.0) | 23 (79.3) | 0.573 | 0.203 |
| Diabetes | 22 (32.4) | 11 (25.6) | 10 (40.0) | 9 (31.0) | 0.668 | 0.849 |
| Smoking | 10 (14.7) | 4 (9.3) | 7 (28.0) | 2 (6.9) | 0.135 | 0.828 |
| Hypercholesterolemia | 16 (23.5) | 6 (14.0) | 3 (12.0) | 5 (17.2) | 0.478 | 0.303 |
| Initial NIHSS score | 15.0 [11.8–19.0] | 17.0 [13.0–20.0] | 17.0 [14.0–22.0] | 18.0 [15.0–21.0] | 0.054‡ | 0.012 |
| Atrial fibrillation | 41 (60.3) | 29 (67.4) | 15 (60.0) | 19 (65.5) | 0.861 | 0.714 |
| Occlusion sites | 0.423 | 0.158 | ||||
| Internal carotid artery | 15 (22.1) | 10 (23.3) | 10 (40.0) | 11 (37.9) | ||
| Middle cerebral artery | 42 (61.8) | 28 (65.1) | 12 (48.0) | 13 (44.8) | ||
| Posterior circulation | 11 (16.1) | 5 (11.6) | 3 (12.0) | 5 (17.3) | ||
| Use of intravenous tPA | 29 (42.7) | 19 (44.2) | 7 (28.0) | 9 (31.0) | 0.405 | 0.162 |
| Use of BGC | 40 (58.8%) | 25 (58.1%) | 10 (40.0%) | 9 (31.0) | 0.039‡ | 0.006 |
| Size of stent retriever | 0.232 | 0.114 | ||||
| 4/15 | 1 (1.5) | 1 (2.3) | 2 (8.0) | 1 (3.4) | ||
| 4/20 | 66 (97.0) | 40 (93.0) | 20 (80.0) | 27 (93.2) | ||
| 6/30 | 1 (1.5) | 2 (4.7) | 3 (12.0) | 1 (3.4) | ||
| Time from onset to puncture, min | 190.0 [150.0–313.0] | 210.0 [153.0–311.0] | 205.0 [150.0–372.0] | 229.0 [160.0–411.0] | 0.571 | 0.201 |
| Time from puncture to recanalization, min | 45.0 [34.0–64.5] | 65.0 [55.0–99.0] | 120.0 [82.0–146.0] | NA | 0.001* | 0.001 |
| Thrombus density, corrected HU | 54.0 [50.1–59.4] | 51.0 [46.8–55.9] | 53.9 [47.7–60.1] | 54.7 [52.2–60.6] | 0.050‡ | 0.481 |
| Thrombus volume, mm3 | 63.9 [37.9–146.6] | 122.7 [74.6–210.1] | 157.1 [108.9–187.5] | 173.7 [73.2–289.2] | 0.001† | 0.001 |
Values are mean ± standard deviation, number (%), or median [interquartile range]. aAnalysis of variance, Kruskal-Wallis test, or chi-square or Fisher’s exact test. bAnalysis of variance for trend, Jonckheere-Terpstra test, or Mantel-Haenszel chi-square test. Multiple comparisons were calculated by Bonferroni-corrected Dunn procedure or Bonferroni-corrected chi-square test for initial NIHSS score, use of BGC, time from puncture to recanalization, thrombus density, and thrombus volume. *First-pass recanalization vs. 2- or 3-pass recanalization, P < 0.001; First-pass recanalization vs. ≥4-pass recanalization, P < 0.001; 2- or 3-pass recanalization vs. ≥4-pass recanalization, P < 0.001. †First-pass recanalization vs. ≥4-pass recanalization, P = 0.016; First-pass recanalization vs. no recanalization, P = 0.006. ‡>0.05 on multiple comparisons. NIHSS, National Institutes of Health Stroke Scale; tPA, tissue plasminogen activator; BGC, balloon-guiding catheter; HU, Hounsfield unit; NA, not applicable.