Definite vs no or questionable histologic damage to carotid arteries under various conditions of catheter testing in vivo
| Condition Tested | Definite Damage (%) | No/Questionable Damage (%) | Odds Ratio | 95% CI | P Value* |
|---|---|---|---|---|---|
| Arterial stasis (n = 24) | 4 | 96 | 3.0 | 0.36–137 | .44 |
| Normal flow (n = 70) | 11 | 89 | |||
| Current ≤300 mA (n = 58) | 0 | 100 | 0 | 0–0.21 | .0001 |
| Current > 300 mA (n = 36) | 25 | 75 | |||
| Activations ≤1 min (n = 52) | 6 | 94 | 0.37 | 0.056–1.9 | .29 |
| Activations > 1 min (n = 42) | 14 | 86 | |||
| Work ≤100 J (n = 68) | 3 | 97 | 0.082 | 0.008–0.5 | .0015 |
| Work >100 J (n = 26) | 27 | 73 | |||
| Saline drip ≤2 mL/min (n = 39) | 15 | 85 | 3.2 | 0.61–21 | .16 |
| Saline drip > 2 mL/min (n = 55) | 5 | 95 | |||
| ≤5°C catheter tip coil temperature rise (n = 36) | 0 | 100 | 0 | 0–0.36 | .0022 |
| > 5°C temperature rise (n = 29) | 24 | 76 | |||
| MR and x-ray guidance (n = 45) | 11 | 88 | 1.9 | 0.35–13 | .47 |
| X-ray guidance only (n = 49) | 6 | 94 |
CI indicates confidence interval; J, Joules; mA, milliamperes.
Note:—Definite damage denotes a histologic score of 2; questionable damage, histologic score of 1; and no damage, histologic score of 0.
↵* P value = 2-tailed Fisher exact test.