A Medical Device Daily

A Worcester Polytechnic Institute (WPI; Worcester, Massachusetts) research team has received a four-year, $1.4 million award from the National Institutes of Health to continue a study of arterial plaque.

According to the team, this research could lead to tools that will enable physicians to predict the likelihood of plaque rupture, which is responsible for most heart attacks and strokes. Led by Dalin Tang, PhD, professor of mathematical sciences and biomedical engineering at WPI, the team is collaborating with researchers at Washington University (St. Louis) and the University of Washington (Seattle) on the research, which combines sophisticated computer modeling with an array of diagnostic technologies to more accurately chart the development of atherosclerotic plaque in the coronary arteries.

Arterial plaques are complex structures made up of cholesterol and other fats, calcium, fibrin, and other materials. When they reach an advanced stage, plaques may develop a thin, membranous or fibrous cap. When this is torn open, it releases the contents of the plaque into the bloodstream. Plaque rupture causes some 60% of sudden, unexpected heart attacks, the researchers note. While the link between plaque build-up and cardiovascular disease has long been recognized, the factors that cause plaques to form, grow and rupture have been less clearly understood, according to the research team.

Better understanding the evolution of arterial plaque is important, Tang says, given the central role it plays in cardiovascular disease. As plaque deposits grow they cause a narrowing of arteries (called stenosis), which diminishes the amount of oxygen and nutrients blood can carry to the body and puts increasing stress on the heart. When plaques rupture, a blood clot typically forms at the site and may block the artery. Such a blockage in a coronary artery leading to the heart is called a myocardial infarction or a heart attack. A similar blockage of the carotid artery leading to the brain is a stroke.

Using computational models, MRI scans of volunteers, and histological studies of diseased arteries, Tang and his team has spent several years investigating mechanisms governing plaque progression and factors and indices that could be used to predict potential plaque rupture. Tang published the first paper about this multi-component plaque model in 2004.

The new NIH award will enable the team to extend this research. Combining such techniques as patient-specific, image-based computational modeling, intravascular ultrasound, angiography, MRI, and mechanical testing to analyze atherosclerotic coronary plaques, the team aims to zero in on what factors – including the forces from blood flow, pressure, and heart motions – best assess quantitatively which of those plaques are most likely to rupture.

Since 60% of all heart attacks and strokes are caused by such ruptures and occur without advanced notice, doctors err on the side of caution and may recommend more surgical remedies than are actually necessary, Tang says. In fact, he notes, only one out of 20 carotid endarterectomies currently performed is likely necessary.

Currently, the trigger for these surgeries is a high level of arterial stenosis. However, with better diagnostic approaches, the trigger might, instead, be identification of arterial plaque with a high potential to rupture, with plaque morphology, tissue components, and mechanical forces all taken into consideration. By developing better diagnostic tools, Tang's team hopes to improve plaque assessment techniques for early diagnosis, treatment and prevention of cardiovascular disease.

In other grant activity, Pathways Hospice Foundation (Sunnyvale, California) said it recently received a $75,000 grant from the Washington Hospital Healthcare Foundation. The grant will support hospice care and services to patients residing within the Washington Township Health Care District, which includes Fremont, Newark, Union City, part of South Hayward, and unincorporated Sunol, Pathways noted.

“Washington Hospital and the Washington Hospital Healthcare Foundation have a long standing partnership with Pathways Hospice,“ said Nancy Farber, CEO of Washington Hospital Healthcare System. “Pathways plays a critical role in the full continuum of health care services offered locally and we support their commitment in providing high quality and compassionate end-of-life care to patients in our community.“