Prognostic implications of increased and final quantitative flow ratios in patients treated with drug-coated balloons physiological evaluation after DCB in de novo lesions.

Background: Few studies investigated the implications of post-PCI QFR and post-PCI ΔQFR (absolute increase of QFR) in de novo lesions of small coronary disease after drug-coated balloon (DCB).

Objectives: We sought to investigate the prognostic implications of post-PCI QFR and post-PCI ΔQFR in patients who received DCB only.

Methods: Patients were divided according to the optimal cutoff value of the post-PCI QFR and the post-PCI ΔQFR. The primary outcome was major adverse cardiovascular events (MACE), including target vessel revascularization (TVR), cardiac death, and myocardial infarction (MI).

Results: The optimal cutoff values of QFR and ΔQFR for the MACE rate were 0.86 and 0.57, respectively. There were 175 patients (61.2%) with a high QFR (≥ 0.86) and 113 patients (39.5%) with a high ΔQFR (≥ 0.57) after PCI. The MACE rate was significantly higher in patients with a low QFR compared to a high QFR (5.7% vs. 27.0%, hazard ratio [HR]: 3.632, 95% confidence interval [CI]: 1.872 to 7.044, P < 0.001). The MACE rate was higher in patients with a low ΔQFR increase compared to those with high ΔQFR (4.4% vs. 20.2%, HR: 4.700, 95%CI: 2.430 to 9.089, P = 0.001). In multivariable model, a low post-PCI QFR and a low post-PCI ΔQFR was independent predictor of MACE (adjusted HR: 4.071, 95%CI: 2.037 to 8.135, P = 0.001).

Conclusions: After DCB in de novo lesions of small coronary disease, both post-PCI QFR and ΔQFR showed similar prognostic implications in MACE.