Outcomes of PIANO Score for No-Reflow in Patients Undergoing Primary Percutaneous Coronary Intervention: A Retrospective Study

BACKGROUND: The no-reflow phenomenon, characterized by inadequate myocardial reperfusion despite successful epicardial vessel revascularization, remains a significant challenge in the management of patients undergoing primary percutaneous coronary intervention (PCI) for acute coronary syndromes. The Predictive Angiographic Index for No-Reflow (PIANO) score has emerged as a potential tool for risk stratification in this context. This study aims to evaluate the predictive performance of the PIANO score and its implications for clinical practice. METHODS: A retrospective analysis was conducted on a cohort of 2291 patients who underwent primary PCI for acute coronary syndromes. The patients were stratified into No-Reflow (n=1054) and No No-Reflow (n=1237) groups based on post-procedural angiographic findings. Baseline characteristics, angiographic features, procedural details, and clinical outcomes were compared between the groups. The performance of the PIANO score in predicting no-reflow and its association with clinical outcomes were assessed. RESULTS: The PIANO score exhibited good predictive capabilities, with an area under the curve (AUC) of 0.77 for predicting TIMI flow grade 0/1 (sensitivity: 0.72, specificity: 0.82) and an AUC of 0.78 for predicting myocardial blush grade 0/1 (sensitivity: 0.88, specificity: 0.67). Patients in the No-Reflow group displayed a higher prevalence of angiographic complexities, including tortuosity, calcification, and side branches. Complications, including contrast-induced nephropathy, major bleeding, stroke, ventricular arrhythmias, cardiogenic shock, reinfarction, and stent thrombosis, were significantly more frequent in the No-Reflow group. CONCLUSION: The PIANO score shows promise as a predictive tool for identifying patients at risk of developing no-reflow during primary PCI.