Prognostic Value of Intravascular Ultrasound in Patients With Coronary Artery Disease

Abstract

Background: It has been shown that intravascular ultrasound (IVUS) and radiofrequency (RF-)IVUS can detect high-risk coronary plaque characteristics.

Objectives: The authors studied the long-term prognostic value of (RF-)IVUS-derived plaque characteristics in patients with coronary artery disease (CAD) undergoing coronary angiography.

Methods: From 2008 to 2011, (RF-)IVUS was performed in 1 nonstenotic segment of a nonculprit coronary artery in 581 patients undergoing coronary angiography for acute coronary syndrome (ACS) or stable angina. The pre-defined primary endpoint was major adverse cardiovascular events (MACE), defined as the composite of all-cause death, nonfatal ACS, or unplanned revascularization. Hazard ratios (HRs) were adjusted for age, sex, and clinical risk factors.

Results: During a median follow-up of 4.7 years, 152 patients (26.2%) had MACE. The presence of a lesion with a minimal luminal area ≤4.0 mm² was independently associated with MACE (HR: 1.49; 95% CI: 1.07 to 2.08; p = 0.020), whereas the presence of a thin-cap fibroatheroma lesion or a lesion with a plaque burden ≥70% on its own were not. Results were comparable when the composite endpoint included cardiac death instead of all-cause death. The presence of a lesion with a plaque burden of ≥70% was independently associated with the composite endpoint of cardiac death, nonfatal ACS, or unplanned revascularization after exclusion of culprit lesion-related events (HR: 1.66; 95% CI: 1.06 to 2.58; p = 0.026). Likewise, each 10-U increase in segmental plaque burden was independently associated with a 26% increase in risk of this composite endpoint (HR: 1.26 per 10-U increase; 95% CI: 1.03 to 1.52; p = 0.022).

Conclusions: IVUS-derived small luminal area and large plaque burden, and not RF-IVUS-derived compositional plaque features on their own, predict adverse cardiovascular outcome during long-term follow-up in patients with CAD. (The European Collaborative Project on Inflammation and Vascular Wall Remodeling in Atherosclerosis-Intravascular Ultrasound Study [AtheroRemoIVUS]; NCT01789411).

Keywords: atherosclerotic burden; cardiovascular outcome; coronary plaque characteristics; intravascular ultrasound; prognosis; radiofrequency.