Background: Percutaneous coronary intervention (PCI) for chronic total occlusions (CTO) remains a challenge. Multislice computed tomographic coronary angiography (CTCA) allows noninvasive evaluation of the coronary artery by visualizing vessel trajectory and morphological features at the occluded site. The aim of this study was to assess the value of CTCA to predict the success of guidewire crossing in PCI to treat CTOs.
Methods: We performed CTCA in patients with CTOs (of > 3 months' duration); 110 lesions were scanned. Wiring success was defined as complete crossing of the guidewire past the occluded site. Correlation of the following morphological parameters with wiring success was analyzed: target vessel bending (defined as > 45 degrees), shrinkage, severe calcification, presence of side branches, stump morphology, in-stent occlusion and occlusion length.
Results: Wiring success was obtained in 93 lesions (85%). In the unsuccessful group, bending, shrinkage and severe calcification were significantly higher compared to the successful group (76% vs. 18%, p < 0.0001; 29% vs. 4%, p = 0.0005; 41% vs. 18%, p = 0.0356, respectively). The wiring success rate was significantly lower in cases with bending, shrinkage and severe calcification (57% vs. 95%, p < 0.0001; 44% vs. 88%, p = 0.0005; 71% vs. 88%, p = 0.0356, respectively). Stump morphology, in-stent occlusion or occlusion length did not significantly affect the outcome. Multivariate analysis showed that bending, shrinkage and severe calcification remained significant independent predictors of wiring failure.
Conclusion: Bending, shrinkage and severe calcification are significant predictors for wiring success. CTCA provides a practical determinant of the outcomes in PCI to treat CTOs.