To explore the changes of endovascular lumen after drug balloon therapy for coronary artery in-stent restenosis in patients with unstable angina pectoris.

Ninety-six patients with unstable angina pectoris who had previously undergone coronary artery drug-eluting stent implantation and developed in-stent restenosis were tested by coronary arteriography at the Affiliated Jiangyin Hospital of College of Medicine of Southeast University. The patients were divided into either a drug balloon therapy group (47 cases) or a Nano stent implantation group (49 cases). The minimal intima cavity area, minimum bracket section area, and neointimal area were compared at postoperative 12 months by intravascular unltrasound (IVUS). Cardiovascular events and bleeding events were compared during postoperative 12 months.

The minimal intima cavity area and minimum bracket section area were significantly smaller in the drug balloon therapy group than in the Nano stent implantation group immediately after operation [(10.8±2.8) mm² vs (11.8±3.2) mm²; (11.2±2.9) mm² vs (12.0±3.2) mm², P=0.025 and 0.042, respectively]. There were seven cases of cardiovascular events in the drug balloon therapy group and nine cases in the Nano stent implantation group during postoperative 12 months (P=0.699). There was no significant difference in the minimum intimal cavity area between the drug balloon group and the Nano stent group [(10.6±2.6) mm² vs (10.6±2.6) mm²; P=0.896]. Intimal hyperplasia was found in both groups, but the neointimal area was (0.30±0.12) mm² in the drug balloon therapy group and (0.39±0.15) mm² in the Nano stent implantation group at postoperative 12 months (P=0.845). There was also no significant difference in minimum bracket section area at postoperative 12 months between the two groups [(10.9±2.7) mm vs (11.2±3.0) mm², P=0.723].

Drug-eluting balloon therapy for in-stent restenosis is clinically safe and reliable compared with Nano stent implantation.