Risk Assessment of Side Branch Compromise After Coronary Bifurcation Stenting ― A Substudy of the 3D-OCT Bifurcation Registry

Abstract

Background: Side branch (SB) occlusion during bifurcation stenting is a serious complication. This study aimed to predict SB compromise (SBC) using optical coherence tomography (OCT). Methods and Results: Among the 168 patients who enrolled in the 3D-OCT Bifurcation Registry, 111 bifurcation lesions were analyzed to develop an OCT risk score for predicting SBC. SBC was defined as worsening of angiographic SB ostial stenosis (≥90%) immediately after stenting. On the basis of OCT before stenting, geometric parameters (SB diameter [SBd], length from proximal branching point to carina tip [BP-CT length], and distance of the polygon of confluence [dPOC]) and 3-dimensional bifurcation types (parallel or perpendicular) were evaluated. SBC occurred in 36 (32%) lesions. The parallel-type bifurcation was significantly more frequent in lesions with SBC. The receiver operating characteristic curve indicated SBd ≤1.77mm (area under the curve [AUC]=0.73, sensitivity 64%, specificity 75%), BP-CT length ≤1.8mm (AUC=0.83, sensitivity 86%, specificity 68%), and dPOC ≤3.96mm (AUC=0.68, sensitivity 63%, specificity 69%) as the best cut-off values for predicting SBC. To create the OCT risk score, we assigned 1 point to each of these factors. As the score increased, the frequency of SBC increased significantly (Score 0, 0%; Score 1, 8.7%; Score 2, 28%; Score 3, 58%; Score 4, 85%; P<0.0001). Conclusions: Prediction of SBC using OCT is feasible with high probability.