Multivariate preprocedural predictors of prolonged observation
| Odds ratio | 95% CI | p Value | |
| Ostial lesion | 1.6 | 1.2 to 2.5 | 0.0005 |
| PTCA > 1 lesion | 1.8 | 1.1 to 2.3 | 0.02 |
| Restenotic | 1.7 | 1.0 to 2.7 | 0.03 |
CI, confidence interval; PTCA, percutaneous transluminal coronary angioplasty.