Safety and Efficacy of DCB Therapy for de Novo Lesions Under the Guidance of QFR in CHD Patients (UNIQUE-DCB-I Study )

Since Gruntzig successfully performed percutaneous coronary balloon angioplasty in 1977, percutaneous coronary intervention has developed rapidly. From bare metal stents to drug-eluting stents (DES), the symptoms and prognosis of patients with coronary heart disease (CHD) have been greatly improved. Although DES has reduced the probability of in-stent restenosis (ISR) and thrombosis compared with BMS since its clinical application, it can not completely solve this problem. Even if the new generation of DES requires revascularization, the incidence of ISR is still as high as 5%-10%. DES treatment is associated with delayed endothelial healing, late acquired poor stent adherence and new atherosclerosis, which lead to late ISR and thrombosis. In addition, DES is still not ideal for the treatment of small vessel disease, diffuse long lesion and bifurcation lesion. Therefore, drug coated balloon (DCB) has attracted people's attention. Balloon-loaded antiproliferative drugs can fully release the drugs to the vascular wall during balloon dilation, which can inhibit the restenosis process from the beginning of injury, and show good efficacy and safety in some specific lesions. Many clinical studies have shown that DCB has good efficacy and safety in some specific lesions (ISR, small vessel disease, bifurcation disease, in situ lesion). Especially in the treatment of ISR, researchers believe that its efficacy is not inferior to DES, and it has the advantage of non-metal residues.

Quantitative flow ratio (QFR) is the second generation FFR detection method based on angiographic images. The diagnostic accuracy of QFR 0.80 for myocardial ischemic stenosis was 92.7%. Compared with QCA, the positive predictive value and negative predictive value of QFR were also significantly better than those of QCA. The latest FAVOR II results also confirm that QFR is more sensitive and specific in diagnosing myocardial ischemia caused by coronary artery stenosis than QCA, and confirm the feasibility of using QFR online in catheter lab to evaluate the functional significance of coronary artery critical lesions. However, there is no report on the treatment of de novo lesions in patients with coronary heart disease by DCB under the guidance of QFR. The aim of this study was to evaluate the safety and efficacy of drug balloon therapy for de novo lesions in patients with CHD under the guidance of QFR compared with DES implantation.