Study Brings Value of Echocardiography Into Focus

(HealthDay News) -- The advanced imaging technique called contrast echocardiography had a significant impact on the diagnosis and treatment of people hospitalized with heart disease, a new study found.

Echocardiography bounces sound waves into the body to get a detailed image of the moving heart. If that image isn't clear enough, it can be improved by injecting a substance, called a contrast agent, that reflects the sound waves better.

"After contrast echocardiography, the percentage of uninterpretable studies decreased from 11.7 percent to 0.3 percent, and technically difficult studies decreased from 86.7 percent to 9.8 percent," said a report published online Feb. 11 in the Journal of the American College of Cardiology.

"The importance of the study is that it is really the first time that we measured the impact of contrast echocardiography on assessment of ventricular function," said study leader Dr. William A. Zoghbi, professor of medicine and director of the Cardiovascular Imaging Center at the Methodist DeBakey Heart and Vascular Center in Houston. "It measured the impact of it in clinical practice -- how does contrast echocardiography influence clinical management," Zoghbi said.

Ventricular function is a measure of the heart's blood-pumping ability.

In this trial of 632 patients, use of the technique avoided additional diagnostic procedures in 33 percent of cases and altered drug management in 10 percent of cases, Zoghbi said.

Contrast echocardiography was most useful in the intensive care unit, he said. "The individuals there are usually sicker yet more highly instrumented, so usually studies are more difficult," Zoghbi said. "This is crucial for day-to-day patient management, particularly for hospitalized patients."

The technology is widely available in U.S. hospitals, he said. "What we've shown is that contrast echocardiography is important in complex cases, where the first images are not clear enough," Zoghbi said. "In our experience, we use it in about 15 percent of patients that are hospitalized."

Contrast echocardiography has sometimes been controversial. The U.S. Food and Drug Administration placed a black-box warning on contrast agents in 2007, following reports of deaths and severe adverse reactions. The agency later eased its stance.

"I think it is pretty much a settled issue," Zoghbi said. "The majority of the contraindications have been changed by the FDA."

Dr. Kevin Wei, associate professor of medicine at the Oregon Health & Science University, said the new study shows that "the impact of contrast echocardiography extends to multiple situations. The emergency room is definitely one of them, where a patient is evaluated for chest pain to determine whether the cause is a heart attack.

"But," he added, "it also allows picking up blood clots that have not been seen before and, in general, by getting more diagnostic information to begin with, potentially avoiding the risks associated with additional testing."

More information
To learn more about echocardiography, visit the U.S. National Library of Medicine.