Short- and long-term functional results following drug-coated balloons versus drug- eluting stents in small coronary vessels: The RESTORE quantitative flow ratio study.

Background Immediate and long-term functional outcomes after percutaneous treatment of small vessel disease (SVD) with drug-coated balloon (DCB) versus drug-eluting stent (DES) remain unknown. The study sought to investigate whether treatment of de novo SVD with DCB yields similar functional results compared with DES, as judged with angiography-based quantitative flow ratio (QFR). Methods and results QFR was measured at pre-procedural, post-procedural and 9-month angiography in all available subjects from the non-inferiority RESTORE SVD China trial, in which patients were randomized to Restore DCB (n = 116) or Resolute DES (n = 114) study arms. Primary outcome of this analysis was 9-month QFR. Pre-procedural, post-procedural and 9-month QFR was performed in 84.8% (195/230), 83.0% (191/230) and 93.8% (181/193) cases, respectively. At 9 months, the QFR of DCB showed no significant difference to DES (0.88 ± 0.23 vs. 0.92 ± 0.12, p = 0.12). Both 9-month QFR and the QFR difference between post-procedure and 9-month follow-up were correlated with angiographic percentage of diameter stenosis and late loss, and predictive of 2-year clinical outcome. Conclusions Treatment of coronary SVD with DCB resulted in similar 9-month functional results compared with DES. This study provides evidences to the value of QFR as a mean of evaluating device performance after coronary revascularization. Clinical trial registration URL: https://www.clinicaltrials.gov; ClinicalTrial.gov: Identifier: NCT02946307.