Potential Predictors of Side-Branch Occlusion in Bifurcation Lesions after Percutaneous Coronary Intervention: A Coronary CT Angiography Study

Abstract

To identify potential predictors of side-branch occlusion after main-vessel (artery) stent implantation in bifurcation lesions by using coronary computed tomography (CT) angiography. This retrospective study was approved by the institutional review board; informed consent was waived. Sixty-five patients with de novo bifurcation lesions underwent coronary CT angiography before percutaneous coronary intervention. By defining side-branch occlusion as Thrombolysis in Myocardial Infarction flow grade 2 or lower, coronary CT angiography plaque characteristics associated with side-branch occlusion (ie, plaque morphology and composition) were analyzed. A multiple logistic regression analysis was undertaken to determine independent potential predictors of side-branch occlusion. Of 65 patients enrolled, 12 patients (18%) had side-branch occlusion after main-vessel stent implantation. Patients with side-branch occlusion had larger mean plaque thickness in the side-branch side of the proximal main vessel (2.29 mm ± 1.87 [standard deviation] vs 1.29 mm ± 1.43, P = .043), larger plaque thickness in the noncarinal side of the side branch (1.43 mm ± 1.18 vs 0.51 mm ± 0.65, P < .001), smaller side-branch lumen diameter (1.24 mm ± 0.74 vs 1.87 mm ± 0.71, P = .007), and higher diameter stenosis (50.9% ± 24.0 vs 25.5% ± 25.3, P = .002) compared with those without side-branch occlusion. The cutoff value of proximal main vessel plaque thickness was 2.7 mm (area under the curve [AUC], 0.67; 95% confidence interval [CI]: 0.48, 0.86) and of side-branch-diameter stenosis was 40% (AUC, 0.79; 95% CI: 0.67, 0.92). Lesions with plaque thickness in proximal main vessel greater than 2.7 mm and side-branch-diameter stenosis greater than 40% were associated with a 5.6-fold and 6.2-fold, respectively, increased risk of side-branch occlusion. Potential coronary CT angiography predictors of side-branch occlusion in bifurcation lesions are plaque thickness in the side-branch side of the proximal main vessel, plaque thickness in the noncarinal side of the side branch, side-branch lumen diameter, and side-branch-diameter stenosis. These potential predictors might guide operators planning the optimal strategy for treating bifurcation lesions.