Washington University cardiologists 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 noninvasive technique, which involves the use of gadolinium contrast-enhanced cardiac MRI. Gadolinium is not radioactive and makes areas of inflamed arteries and heart muscle appear brighter on images. Researchers found that the brightness corresponds to evidence of coronary artery disease.
If larger studies confirm the results, the noninvasive test could reduce the number of coronary angiograms, which require the use of a catheter to look for dangerous plaque on arterial walls.
The study involved 29 pediatric heart transplant patients. Samuel A. Wickline, MD, professor of medicine in the cardiovascular division, is the senior author of the study. Colleagues include Charles E. Canter, MD, professor of pediatrics; and medical student Mohammad H. Madani, a Doris Duke Clinical Fellow.
Researchers do note that gadolium is sometimes toxic to the kidney, so the technique is not appropriate for patients with poor kidney function. They also note that clear contrast-enhanced MRIs are difficult to obtain in very young children because of their high heart rates.
The new method is described in the July 2, 2012 online publication of the Journal of Heart and Lung Transplantation. The investigators are now in the process of developing a larger study to confirm and refine the results.