Clinical Implication of Quantitative Flow Ratio to Predict Clinical Outcomes in De Novo Coronary Lesions After Drug-Coated Balloon Angioplasty.

Purpose: The association between the intra-procedure quantitative flow ratio (QFR) and clinical outcomes after drug-coated balloon (DCB) angioplasty has not been investigated. This study aimed to investigate the clinical predictive value of pre-DCB QFR, a functional assessment of lesion preparation, for clinical outcomes in de novo coronary lesions after DCB angioplasty.

Methods: This retrospective study included 170 consecutive patients undergoing DCB angioplasty for 177 de novo coronary lesions between January 2021 and December 2022. The QFR was computed at baseline, pre-DCB, and post-DCB. The primary endpoint was major adverse cardiac events (MACE), defined as a composite of all-cause death, cardiac death, target vessel myocardial infarction, and target lesion revascularization.

Results: During 2-year follow-up, 37 patients with 38 lesions have experienced MACE. The pre-DCB QFR, measured after pre-dilation, was significantly lower in the MACE group. Receiver operator characteristic curve analysis showed the optimal pre-DCB QFR cut-off value for predicting MACE was 0.925 (area under curve = 0.782, 95% confidence interval [CI] 0.702-0.861, sensitivity = 78.9%, specificity = 74.8%, p < 0.001). A pre-DCB QFR < 0.925 was associated with a significantly higher risk of MACE compared with a value > 0.925 (46.1% vs. 7.1%, p < 0.001). In multivariable Cox regression analyses, pre-DCB QFR < 0.925 was associated with an over sixfold increased risk of MACE (hazard ratio = 7.483, 95% CI 3.363-16.653, p < 0.001).

Conclusion: The pre-DCB QFR was a promising predictor of unfavorable clinical outcomes in de novo coronary lesions after DCB angioplasty.