Image courtesy of Infraredx
December 9, 2014 — A study published in the Journal of the American College of Cardiology (JACC) shows intravascular near-infrared spectroscopy (NIRS) can identify lipid core-containing plaques, implicated in most heart attacks. The study shows the technology might be used as a means to predict the risk of future major adverse cardiac and cerebrovascular events (MACCE).
In the study, patients who presented with symptoms associated with limited blood supply to the heart also underwent NIRS imaging to evaluate the Lipid Core Burden Index (LCBI) in an artery that was not directly implicated in causing their symptoms. The results, which were published online on Dec. 8 and will appear in the Dec. 16 print edition of JACC, demonstrated that patients with an LCBI ? 43 in a non-culprit artery had a fourfold risk of MACCE such as heart attack or stroke within the following year. In addition, the study concluded that non-culprit vessel LCBI reflects vascular vulnerability of the larger coronary tree.
Lipid-core plaque is a type of fatty coronary artery plaque suspected to be prone to rupture, which leads to the formation of blood clots that can cause heart attacks. Only NIRS can detect lipid-core plaque and provide a quantitative measurement in the form of an LCBI. Intravascular NIRS is commercially available through the TVC Imaging System from Infraredx Inc., a U.S. Food and Drug Administration (FDA)-cleared dual-modality imaging system capable of rapidly, specifically and reliably identifying lipid-core plaques using NIRS and providing vessel structure information using enhanced intravascular ultrasound (IVUS).
“Our findings suggest that the use of NIRS imaging to identify and quantify lipid-core plaque in the non-culprit arteries, which would otherwise remain undetected by coronary angiography, could be a viable tool to assess the vascular vulnerability of the larger coronary tree,” said Rohit M. Oemrawsingh, M.D., M.Sc, the study’s first author at the Thoraxcenter, department of cardiology, Erasmus MC, Rotterdam, the Netherlands.
The ATHEROREMO-NIRS Study, a sub-study of the European Collaborative Project on Inflammation and Vascular Wall Remodeling in Atherosclerosis (ATHEROREMO), is a prospective, single-center, observational study that enrolled 203 patients referred for coronary angiography due to stable angina (chest pain) or an acute coronary syndrome (ACS), a combination of symptoms resulting from the blockage of blood supply to the heart. NIRS imaging was performed and an LCBI measurement was obtained for a pre-defined segment of a non-culprit coronary artery that was at least 40 mm in length and with < 50 percent stenosis confirmed by angiography. The primary endpoint was the incidence of MACCE, defined as all-cause mortality, non-fatal ACS, stroke and unplanned coronary revascularization during one-year follow-up.
The research team hopes that the ongoing Lipid-Rich Plaque Study and PROSPECT II/ABSORB Study will provide further validation of their results.
For more information: www.infraredx.com