Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Noninvasive imaging technique may help kids with heart transplants

13.07.2012
Cardiologists at Washington University School of Medicine in St. Louis have developed a noninvasive imaging technique that may help determine whether children who have had heart transplants are showing early signs of rejection. The technique could reduce the need for these patients to undergo invasive imaging tests every one to two years.

The new method is described online in the Journal of Heart and Lung Transplantation.

The invasive imaging test, a coronary angiogram, involves inserting a catheter into a blood vessel and injecting a dye to look for dangerous plaque on the walls of arteries feeding blood to the heart. This plaque build-up indicates coronary artery disease and is a sign that the body may be rejecting the new heart. Since pediatric heart transplant patients are at high risk of developing coronary artery disease, doctors monitor their arteries on a regular basis. But recurring angiograms become problematic.

“Many of these children have undergone so many operations, we have lost access to their big blood vessels,” says Charles E. Canter, MD, professor of pediatrics. “Sometimes it’s impossible to do catheterization procedures on them.”

Based on experience imaging other types of inflammation in arteries, senior author Samuel A. Wickline, MD, professor of medicine, and his colleagues, including Canter and medical student Mohammad H. Madani, a Doris Duke Clinical Research Fellow, examined whether they could assess coronary artery disease in these children using magnetic resonance imaging (MRI). In this case, the MRI was enhanced with a commonly used contrast agent called gadolinium that is injected into the arteries. Gadolinium is not radioactive and makes areas of inflamed arteries and heart muscle show up brighter on an MRI.

“The brighter it is, the more it is associated with coronary artery disease,” Canter says.

The study included 29 heart transplant patients and eight healthy children who served as controls. The transplant patients underwent standard coronary angiograms as part of their normal care. They also had MRIs of the coronary arteries to examine whether the noninvasive method correlated with the degree of coronary artery disease found in the angiograms. The eight children who served as controls only had MRI scans. The researchers assessing the MRI results were blinded to the results of the transplants patients’ angiograms.

While all of the transplant patients’ angiograms showed evidence of plaque build-up, in only six of them was it severe enough for a diagnosis of coronary artery disease.

These six patients had the brightest coronary arteries on the MRI scans, compared to both the transplant patients without coronary disease and the healthy controls. Still, the 23 transplant patients without diagnosed coronary disease had significantly brighter arteries than the healthy participants. Such evidence demonstrates the need to continue monitoring these patients.

Although the brightness of the arteries on MRI correlated well with a diagnosis of coronary artery disease, gadolinium can be toxic to the kidney, Canter points out. This means the technique can’t be used for patients with poor kidney function. Furthermore, clear images with MRI are difficult in very young children because of their high heart rates. In this study, no participant was younger than age 10. Nevertheless, Canter sees a possible future place for this technique in helping to monitor the progress of coronary artery disease in transplant patients.

“The results of this pilot study were very promising,” Canter says. “But we need to look at more patients. We’re in the process of developing a bigger study to confirm and refine the results. I think eventually this could be used as a screening technique, not so much to eliminate, but to reduce the number of angiograms.”

Madani MH, Canter CE, Balzer DT, Watkins MP, Wickline SA. Noninvasive detection of transplant coronary artery disease with contrast-enhanced cardiac MRI in pediatric cardiac transplants. Journal of Heart and Lung Transplantation. Online July 2, 2012.

This work was supported by the Children’s Discovery Institute, St. Louis Children’s Hospital, Washington University School of Medicine in St. Louis and a Doris Duke Clinical Research Fellowship.

Washington University School of Medicine’s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked sixth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Julia Evangelou Strait | EurekAlert!
Further information:
http://www.wustl.edu

More articles from Medical Engineering:

nachricht Novel PET tracer identifies most bacterial infections
06.10.2017 | Society of Nuclear Medicine and Molecular Imaging

nachricht Teleoperating robots with virtual reality
05.10.2017 | Massachusetts Institute of Technology, CSAIL

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>