Table 5.
Prognostic index: elaboration of fictitious subjects with different combinations of unfavorable predictors for CTO-PCI success and their relative risk (RR) for procedural failure.
| Length | Stump | Bending | CN | Prop | RR |
|---|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 0.0690 | 0.9993 * |
| 0 | 0 | 1 | 0 | 0.1097 | 1.5892 |
| 1 | 0 | 0 | 0 | 0.1354 | 1.9617 |
| 0 | 0 | 0 | 1 | 0.2025 | 2.9343 |
| 1 | 0 | 1 | 0 | 0.2066 | 2.9937 |
| 0 | 1 | 0 | 0 | 0.2332 | 3.3796 |
| 0 | 0 | 1 | 1 | 0.2969 | 4.3024 |
| 0 | 1 | 1 | 0 | 0.3359 | 4.8678 |
| 1 | 0 | 0 | 1 | 0.3492 | 5.0613 |
| 1 | 1 | 0 | 0 | 0.3913 | 5.6709 |
| 1 | 0 | 1 | 1 | 0.4716 | 6.8346 |
| 0 | 1 | 0 | 1 | 0.5104 | 7.3970 |
| 1 | 1 | 1 | 0 | 0.5167 | 7.4882 |
| 0 | 1 | 1 | 1 | 0.6342 | 9.1912 |
| 1 | 1 | 0 | 1 | 0.6878 | 9.9688 |
| 1 | 1 | 1 | 1 | 0.7856 | 11.3858 |
*
Reference value.
According to this index if a patient has none of the unfavorable predictors the relative risk of procedural failure is almost 1 (the easiest and the reference case) and if all four unpropitious predictors are present the relative risk increases by 11.4 times (the most unfavorable case) with regard to the referent case.
CN — case number (< 100 PCIs = 1); Prop — the failure probability