SAN DIEGO – Clinical outcomes were better when stent placement was guided by intravascular ultrasound rather than angiography, based on the results of a trial conducted in China. Unlike previous comparative studies, which focused on patients with more complex lesions, this trial included all patients undergoing drug-eluting stent (DES) placement.
In thetrial, 1,448 all-comer patients receiving DES were randomized to either intravascular ultrasound (IVUS)–guided or angiography-guided implantation, reported Junjie Zhang, PhD, of Nanjing Medical University in China, and colleagues. The study excluded patients who had a life expectancy shorter than 12 months, who were intolerant of dual antiplatelet therapy, and who had severe calcification needing rotational atherectomy.
At 30 days after stent placement, the incidence of target vessel failure was 0.8% in the IVUS group and 1.9% in the angiography group, a nonsignificant trend. However, outcomes were significantly different at 1 year, with target vessel failure occurring in 2.9% of IVUS patients and 5.4% of angiography patients (hazard ratio, 0.530; 95% confidence interval, 0.312-0.901; P = .019).
The work was simultaneously published in the Journal of the American College of Cardiology () .
Despite good results in this and prior studies, uptake of the IVUS procedure is not high in the United States or Europe, according to members of a panel that reviewed the results at the Transcatheter Cardiovascular Therapeutics annual meeting.
“How can people continue to ignore the importance of imaging-guided stent optimization? Even with second-generation DES, the results are consistent across the studies. This is just another piece of irrefutable evidence,” said, chief medical officer at the Cardiovascular Research Foundation, and a discussant at the meeting, sponsored by the Cardiovascular Research Foundation.
That sentiment was generally echoed by the rest of the panel., a professor of medicine at MetroHealth Medical Center in Cleveland, pointed out that the study included a variety of cases, and angiography was performed to a high standard in that arm of the study. “It shows that, even with a good angiographic approach, IVUS still wins. I’m amazed that there’s still some resistance to [IVUS] image guidance,” said Dr. Hodgson.
The ULTIMATE study also found that the procedural time was longer (60.88 minutes vs. 45.49 minutes; P less than .001), and the contrast volume was higher (178.29 mL vs. 161.96 mL; P less than .001) in the IVUS than in the angiography group.
A postprocedure IVUS assessment was performed to determine whether the stent was optimally deployed. The criteria for optimal deployment included minimal lumen area in the stented segment of at least 5 mm2, or 90% of the minimal lumen area at distal reference segment meeting that criteria; a less than 50% plaque burden at the 5 mm of vessel proximal or distal to the stent edge; and no edge dissection involving media greater than 3 mm in length.
In the IVUS group, 53% of patients had optimal placement. The rate of target vessel failure was 1.6% of patients with optimal placement and 4.4% of patients who failed to achieve all optimal criteria (HR, 0.349; 95% CI, 0.135-0.898; P = 0.029). Compared with angiography guidance, IVUS guidance was of similar benefit for patients with either American College of Cardiology/American Heart Association–defined B2/C lesions or A/B1 lesions in terms of the composite endpoint. The significant reduction of clinically driven target lesion revascularization or definite stent thrombosis (HR, 0.407; 95% CI: 0.188-0.880; P = 0.018) based on lesion-level analysis by IVUS guidance was not achieved when patient-level analysis was performed.
“I’m particularly impressed by the analysis of the optimal versus nonoptimal group. If you don’t use IVUS correctly, you don’t get a benefit. The ones [in the IVUS group] who did not get optimal stenting were very similar to the angiographic group,” said Dr. Mintz.
The study was funded by the National Science Foundation of China, Six Talent Peaks Project, Nanjing Health and Family Planning Commission, Nanjing Health Youth Talent Training Project, and the Nanjing Municipal Commission of Science & Technology. None of the study authors had relevant financial disclosures. Dr. Mintz reported received research support from Abbott Vascular and Boston Scientific. He has been a consultant for Boston Scientific, Volcano, and Infraredx. Dr. Hodgson reported received research support and consulted for Volcano.