Predilation, sizing and post-dilation scoring in patients undergoing everolimus-eluting bioresorbable scaffold implantation for prediction of cardiac adverse events: development and internal validation of the PSP score.

Abstract

The aim of the study was to develop a scoring model to evaluate the quality of bioresorbable vascular scaffold (BVS) implantation and determine the model's usefulness in predicting adverse cardiac events. The implantation technique and clinical outcomes of 1,736 lesions treated with BVS were analysed using the GHOST-EU registry. Predilation, scaffold sizing, and post-dilation (PSP) were scored according to the hazard model derived from the weight of these variables. The primary endpoint was a one-year device-oriented composite endpoint (DoCE) composed of cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularisation. Definite/probable scaffold thrombosis was also evaluated as defined by the Academic Research Consortium. The PSP model performance was evaluated by internal validation. Predilation, correct scaffold sizing, and post-dilation with a non-compliant balloon were performed in 95.7%, 50.2%, and 26.2% of the cases and scored 0.63, 1.96 and 1.93 points, respectively, in the PSP-1 model. PSP-1 was an independent predictor of one-year DoCE (HR 0.75, 95% CI: 0.61-0.93; p=0.007), but with poor calibration and discrimination (AUC 0.611, 95% CI: 0.545-0.677). No patient with a maximum PSP-1 score had scaffold thrombosis, compared to those with a non-maximum PSP-1 score (0% vs. 2.3%; p=0.095). At one-year follow-up, the PSP-1 score was an independent predictor of DoCE. External validation and prospective studies are needed to determine the clinical usefulness of this score.