FrActional Flow Reserve Guided Drug Coated Balloon Only Strategy in De Novo coronarY Lesions (FADDY)

Drug-eluting stent (DES) has been the primary choice for in suit coronary lesions treatment. In comparison to bare-metal stent (BMS), it evidently decreases the rate of restenosis. However, in recent years in-stent restenosis or thrombogenesis caused by acquired stent malapposition in the late stage or by new in-stent atherosclerotic plaques was oberved, which possibly was associated with chronic inflammation stimulation because of residual intravascular metal or polymer coating. Through being expanded around 30 to 60 seconds, drug-coated balloon (DCB) can ensure adequate paclitaxel enter the artery wall, which can inhibit smooth muscle cells hyperplasia without remaining any foreign body. In recent small sample trials, they showed that sole DCB treatment had a good long-term effect when pre-treating ideal in suit coronary lesions (defined as residual stenosis\0.85 after percutaneous transluminal coronary angioplasty (PTCA), the FFR kept unchanged in the 9-month follow up after DCB treatment and there was not MACE happened. However, so far randomized controlled trials with large sample to confirm their non-inferiority compared with DES when treating relatively larger in suit coronary lesions are lacked. Meanwhile, a number of doctors worried about acute cardiovascular occlusion and long-term restenosis. In this study, we assume that in the in suit coronary lesions with FFR\>0.85 after PTCA pre-treatment, DCB treatment is not inferior to DES treatment regarding to middle- and long-term functional recovery.