Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Optical technique identifies vulnerable plaques in cardiac patients

29.03.2005


Imaging technology may someday guide therapy designed to prevent heart attacks



A catheter-based imaging technology called optical coherence tomography (OCT) can successfully identify the characteristics of coronary plaques in patients with various cardiac symptoms. The report from researchers at Massachusetts General Hospital (MGH) will appear in the journal Circulation and has received early online release at http://www.circulationaha.org/.

"More than 1.2 million people die from coronary artery disease every year, a quarter of them before or soon after arriving at the hospital," says Ik-Kyung Jang, MD, PhD, director of cardiovascular clinical research in the MGH Cardiology Division and lead author of the current study. "The ability to identify dangerous plaques before they rupture and produce a heart attack or sudden cardiac death will be crucial to innovative preventive therapies."


Plaques are deposits of fats, cholesterol and other materials that collect in major arteries, restricting or sometimes blocking blood flow. While some plaques are relatively stable, others are vulnerable to rupture and release their contents into the bloodstream, causing a blood clot to form. Heart attacks and other acute coronary events usually result from the rupture of high-risk, vulnerable plaques in coronary arteries, and the characteristics of those plaques have been determined primarily by autopsy studies.

OCT uses infrared light delivered via fiberoptic catheter to produce high-resolution, cross-sectional images of blood vessels. Study co-authors Guillermo Tearney, MD, PhD, of the MGH Pathology Department and the Wellman Center for Photomedicine at MGH, and Brett Bouma, PhD, also of the Wellman Center, developed the use of OCT to visualize coronary arteries, including vulnerable plaques. The technology developed in their laboratory was used for this first study to examine the structure of plaques in patients with cardiac disease.

The study enrolled patients scheduled to undergo cardiac catheterization for whom angiograms or other imaging techniques had identified the arterial lesion responsible for their symptoms. Participants either had experienced a recent heart attack or had acute coronary syndrome (ACS), a set of symptoms associated with reduced blood supply to the heart muscle. A third group had stable angina, chest pain that occurs with physical or mental stress, which is not usually related to plaque rupture. Clear OCT images of the suspicious lesions were obtained for 20 heart attack patients, 20 with ACS and 17 with stable angina.

Vulnerable plaques are believed to have three major characteristics – a deposit of lipids (fats), a thin cap of fibrous material covering the lipid pool, and infiltration of the immune cells called macrophages. The OCT images showed that the heart attack and ACS patients had more lipid in their plaques and significantly thinner fibrous caps than did the stable angina patients. Overall, vulnerable plaques were identified in 72 percent of the heart attack patients, 50 percent of those with ACS and only 20 percent of stable angina patients.

"This is the first technique that allows us to study the structural changes underlying vulnerable plaques in living patients, and it supports the conclusions of previously reported postmortem studies," says Jang. "We still need to gather more data to confirm these characteristics, and our group will carry out further studies of how plaques develop and rupture. Someday OCT may provide information that will guide treatments to prevent plaque rupture and its disastrous consequences." Jang is an associate professor of Medicine at Harvard Medical School.

Along with the study’s senior author Bouma and Tearney, additional co-authors are Briain MacNeill, MD, Masamichi Takano, MD, and Fabian Moselewski, of the MGH Cardiology Division; Nicusor Iftima, PhD, and Milen Shishkov, PhD, of the Wellman Center; Stuart Houser, MD, and Thomas Aretz, MD, MGH Department of Pathology; and Elkan Halpern, MGH Department of Radiology. The study was supported by grants from the Center for Integration of Medicine and Innovative Technology, for development of the imaging system platform; the National Institutes of Health and Guidant Corporation.

Sue McGreevey | EurekAlert!
Further information:
http://www.circulationaha.org
http://www.mgh.harvard.edu

More articles from Health and Medicine:

nachricht One gene closer to regenerative therapy for muscular disorders
01.06.2017 | Cincinnati Children's Hospital Medical Center

nachricht The gut microbiota plays a key role in treatment with classic diabetes medication
01.06.2017 | University of Gothenburg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>