Comparison between a dedicated stent positioning system and conventional stenting of aorto-ostial lesions: a prospective, multi-center, randomized controlled study

BACKGROUND: The accurate placement of stents for treatment of coronary aorto-ostial lesions (AOLs) is technically challenging. The purpose of this study was to evaluate the efficacy and safety of a stent positioning system with a dedicated nitinol device and compare them with those of the conventional approach for stenting of coronary AOLs. METHODS: In this prospective, multi-center, open-label, randomized study, conducted from November 2015 to April 2019, patients with coronary AOLs that underwent percutaneous coronary intervention (PCI) were randomly allocated (allocation ratio 1:1) using block randomization method to either a stent positioning system group or a conventional technique group. The primary endpoint was the range of stent slippage when positioning. The following secondary endpoints were applied: (I) the extent of swing of the guiding catheters during stent positioning; (II) the rate of accurate stent placement; (III) the procedure time; and (IV) the incidence of major adverse cardiovascular events (MACEs) including cardiac death, myocardial infarction, target lesion revascularization, and stent thrombosis. RESULTS: During the study period, 139 patients with aorto-ostial coronary artery stenosis were included at 5 centers. A total of 69 patients were allocated to the stent positioning system group and 70 patients to the conventional technique group. Angiographic and clinical success were achieved in 100% of the patients included in both groups. The range of stent slippage was significantly shorter in the stent positioning system group than it was in the conventional technique group [0.64 (0.22; 1.35) vs. 1.11 (0.48; 1.72) mm, P=0.01]. The rate of accurate placement of stents was higher in the stent positioning system group than it was in the conventional technique group (74.6% vs. 57.1%, P=0.03). The extent of guiding catheter swing during the stent positioning [0.24 (0.19; 0.53) vs. 0.23 (0.19; 0.53) mm; P=0.95] and the MACEs rates (1.4% vs. 2.9%, P>0.99) were similar between the 2 groups. The procedural time of the stent positioning system was longer than that of the conventional approach [1.00 (0.50; 1.50) vs. 0.80 (0.50; 1.50) min, P=0.09]. CONCLUSIONS: The dedicated stent positioning system was is safer and provides more accurate placement of stents for coronary AOLs than the conventional approach, and the associated prolongation of procedure time is insignificant. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), Unique identifier: ChiCTR2100053869. URL: https://www.chictr.org.cn/showproj.html?proj=133280.