Combined imaging method overcomes angiogram limitations and may help prevent heart attacks
A new cardiovascular imaging technique identifies high-risk plaques within blood vessels and may identify heart attacks before they begin, according to a prospective study published in The Lancet.
A number of recent autopsy studies have revealed vulnerable plaques in vessels surrounding the heart to be underlying causes of most coronary artery disease. And when those buildups rupture to form clots, they lead to a majority of cardiovascular-related sudden deaths.
Near-infrared spectroscopy and intravascular ultrasound proved highly capable at spotting these fatty blockages in nearly 900 patients who suffered a heart attack. Researchers found dangerous plaques were not detected using previous tests, including angiograms.
"We have been working on this study for 10 years,” study co-leader David Erlinge, MD, professor of cardiology at Lund University and consultant in Interventional Cardiology at Skåne University Hospital in Sweden, said in a statement. “This creates a unique opportunity to treat plaques before they cause a heart attack.”
The new method—known as NIRS-IVUS—utilizes infrared light and ultrasound, and is usually performed with a catheter brought to the heart area through the wrist. It’s completed alongside an angiogram, allowing clinicians to see high-fat plaques in yellow via colored maps.
For their study, Erlinge and colleagues included 898 patients treated across 16 hospitals in Sweden, Denmark and Norway. Each suffered a prior heart attack and was treated with balloon dilation and coronary artery stents.
For about 14.4% of patients, new issues arose—including heart disease—within four years of their attack. Untreated plaques were the direct cause in 8% of these cases, the authors reported. The new technique identified more than 3,600 leftover plaques or about four per patient.
The key is that NIRS-IVUS can show what is within the vessel walls, unlike angiogram which only depicts potential plaques as shadows.
"This a major step forward for cardiology," co-author James Muller, MD, of the Division of Cardiovascular Medicine at Brigham and Women's Hospital in Boston, Massachusetts, said in the statement. "This study has demonstrated a superior way to quantify risk at the plaque level and to identify patients who are at increased risk of experiencing adverse cardiac events."
Read the entire study published March 13 here.
Matt joined Chicago’s TriMed team in 2018 covering all areas of health imaging after two years reporting on the hospital field. He holds a bachelor’s in English from UIC, and enjoys a good cup of coffee and an interesting documentary.