"Among patients requiring long coronary stent implantation, the use of IVUS-guided everolimus-eluting stent implantation, compared with angiography-guided stent implantation, resulted in a significantly lower rate of the composite of major adverse cardiac events at one year," Dr. Myeong-Ki Hong of Severance Cardiovascular Hospital and Yonsei University College of Medicine in Seoul, Korea, and colleagues report.
"These differences were primarily due to lower risk of target lesion revascularization," they note in an article online November 10 in JAMA. They presented their findings simultaneously at the American Heart Association Scientific Sessions in Orlando, Fla.
Dr. Hong and colleagues conducted a trial involving 1,400 patients with long coronary lesions between 2010 and 2014 at 20 centers in Korea. They randomized 700 patients to IVUS-guided stent implantation and 700 to angiography-guided stent implantation. They had one-year follow-up results on 94.5%.
Patient mean age was 64 and 69% were men. The mean stented target length was 39.3 mm.
The composite endpoint of major adverse cardiac events, including cardiac death, target lesion-related myocardial infarction (MI), or ischemia-driven target lesion revascularization, occurred in 19 (2.9%) patients who underwent IVUS implantation and 39 (5.8%) patients who underwent angiography-guided implantation (hazard ratio, 0.48; p=0.007).
Cardiac death and target-related MI were not significantly different between the two groups. However, ischemia-driven target lesion revascularization occurred in 17 (2.5%) IVUS
patients and 33 (5%) angiography patients (HR 0.51, p=0.02).
Clinicians performed post-stent balloon dilation more frequently in IVUS patients than in angiography patients (76% vs. 57%, p<0.001), and the mean final balloon size was larger in IVUS patients.
Patients who met IVUS criteria for stent optimization (363, 54%) had significantly greater mean post-intervention minimal lumen area at the stented segment compared with patients who did not meet IVUS criteria.
"The clinical benefit of IVUS-guided (drug-eluting stent) implantation may be attributed to the larger minimal lumen diameter followed by the more frequent adjunct postdilation with a large-sized balloon in the IVUS-guided group," the researchers write.
"To our knowledge, the current study is the first demonstration of the clinical benefit of IVUS guidance in second generation (drug-eluting stent) implantation in an adequately powered randomized clinical trial," they note.
However, even though recent guidelines recommend IVUS-guided implantation for some patients, evidence for improved outcomes based on adequately powered trials remains inadequate, they caution.
Dr. Hong did not respond to a request for comments. Abbott Vascular funded this research. The authors reported no conflicts of interest.