Coronary Angiography‐Derived Murray Law‐Based Quantitative Flow Ratio (μQFR) After De Novo Drug‐Coated Balloon Angioplasty

Background Drug‐coated balloon (DCB) angioplasty has emerged as a stentless alternative for de novo coronary artery disease. However, the prognostic value of post‐procedural angiography‐derived physiology, particularly three‐dimensional (3D) Murray‐law quantitative flow ratio (μQFR), after DCB in native vessels remains unclear. Objectives To quantify the prognostic value of immediate post‐DCB 3D‐μQFR for predicting lesion failure in de novo coronary disease. Methods We conducted an analysis of the prospective CARDIO‐FR registry, including all patients undergoing DCB angioplasty for de novo coronary lesions between January 2018 and December 2024. 3D‐μQFR and quantitative coronary angiography were performed offline by independent analysts. The primary endpoint was the vessel‐oriented composite endpoint (VOCE: cardiac death, target‐vessel myocardial infarction, or target‐vessel revascularization). Results Among 81 patients (87 lesions), VOCE occurred in 33 lesions during median follow‐up of 240 days. Post‐procedural 3D‐μQFR was significantly lower in VOCE lesions (median 76.5 vs. 90.0, p < 0.001). ROC analysis identified optimal μQFR threshold of 0.83 (AUC 0.74). In multivariate and propensity‐matched analyses, μQFR < 0.83 was independently associated with higher VOCE rates (HR 6.01, 95% CI 2.48–14.46, p < 0.0001). Conclusions Immediate post‐DCB 3D‐μQFR independently predicts adverse vessel outcomes in de novo coronary disease. Physiology‐guided optimization of DCB angioplasty may improve long‐term results and warrants prospective validation.