NEW YORK (Reuters Health) – Long-term clinical outcomes of percutaneous intervention of complex coronary bifurcation lesions are significantly better when the procedure is performed with adjunctive intravascular ultrasound (IVUS) guidance, according to a study reported in the American Journal of Cardiology online February 2nd.

Noting the high degree of lesion complexity in their patient population, the authors comment: “In this regard, the role of IVUS in deceasing TLR (target lesion revascularization) may be heightened in patients with the most complex bifurcations lesions.”

Dr. Jasvindar Singh and colleagues at Washington University School of Medicine in St. Louis, Missouri, explain that PCI of bifurcation lesions is challenging and the risk of adverse outcomes is high. They hypothesized that greater imaging precision provided by IVUS compared with angiography might improve outcomes in such cases.

For their study, they analyzed outcomes in 449 patients with bifurcation lesions. Medina classification of lesion complexity was 1,1,1 in 89% of the patients. PCI was performed with IVUS in 247 cases and without IVUS in 202 cases.

During a mean follow-up of 2.5 years, death or myocardial infarction (the composite primary outcome) occurred in 8% of the IVUS group and 21% of the non-IVUS group (p=0.0002), the report indicates. Respective rates of target lesion revascularization were 6% vs 21% and rates of target vessel revascularization were 7% vs 24% (p<0.0001 for both).

“Propensity scores were created for the IVUS versus no-IVUS groups based on patient and lesion characteristics and were used as an adjustment factor in a logistic regression model for each outcome,” the researchers explain.

On that basis, use of IVUS was associated with significantly lower risk of death or MI (odds ratio 0.38; p=0.005), TLR (OR 0.27; p=0.0003) and TVR (OR 0.28; p<0.0001),

In discussing the results, Dr. Singh and colleagues point out that stent underexpansion, which is normally highly associated with stent thrombosis, was seen in 27% of their patients. However, “Remarkably, in the present study no patients in the IVUS group had stent thrombosis.”

They conclude that the results strongly support the utility of IVUS in this setting. “Further study is warranted to evaluate the role of IVUS guidance in improving long-term outcomes after PCI of bifurcation lesions,” they add.

SOURCE:

Long-Term Outcomes With Use of Intravascular Ultrasound for the Treatment of Coronary Bifurcation Lesions

American Journal of Cardiology 2012