Prediction of side branch occlusion in bifurcational lesions during percutaneous coronary interventions by preprocedural coronary computed tomography using the CT bifurcation score

Introduction:
Coronary computed tomographic angiography (CCTA) is a highly diagnostically accurate non-invasive imaging method for a thorough evaluation of atherosclerotic plaques. Many CCTA-based imaging investigations concentrate on bifurcation lesions.

Aim:
To determine whether intraprocedural side branch (SB) obstruction during the percutaneous coronary intervention (PCI) of lesions involving bifurcations might be predicted by preprocedural CCTA.

Material and methods:
This retrospective observational study was conducted on 200 stentable bifurcation lesions of 200 coronary artery disease patients with the SB ≥ 2 mm in diameter. All patients were planned for elective bifurcation PCI after undergoing CCTA for quantitative plaque characterization of both the main vessel and SB to obtain the CT bifurcation score. Then, angiography-based bifurcations were classified using both the Medina classification and the RESOLVE score before PCI of the bifurcation lesions. Most of the cases were managed by the provisional technique.

Results:
The CT bifurcation score was substantially higher in patients with SB occlusion (p < 0.001) with 80% sensitivity and 60% specificity at a cut-off point of 3. There was a borderline significant relation between the Medina score and SB occlusion in the studied cases (p = 0.05) with 60% sensitivity and 40% specificity. The RESOLVE score was unexpectedly an insignificant predictor of SB occlusion (p = 0.25) in our study, with 40% sensitivity and 50% specificity.

Conclusions:
Intraprocedural SB occlusion can be predicted by a comprehensive CCTA evaluation. The CT bifurcation score, a novel and simple points scoring system based on six CCTA parameters, outperformed current angiographic classification or scoring systems for predicting SB occlusion.