Imaging the Heart: The New Frontier
An echo test involves ultrasound -- high-frequency sound waves -- to evaluate the function of heart muscle and valves, the same technology used to ensure a developing baby is healthy. In a cardiac echo test, a wand-like device is used to transmit ultrasound waves against the chest, to produce moving images of the heart.
Advances in echocardiography have improved this already excellent medium, Garcia tells WebMD. "Echo is biologically very safe. It uses no contrast medium, no radiation -- so it can be repeated often. And echo can evaluate the function of the heart muscle and valves better than any modality."
Portable Echo: Laptop-sized echo machines are making the technology more portable than ever before, Garcia tells WebMD. "If you're a paramedic, you can take it in a helicopter or ambulance, and get much information before the patient gets to the hospital. We cannot do that with other devices. In fact, [we] can do echo in space with the astronauts."
Portable echo devices are being used in high school and college sports programs, he says. "There is always a small percentage of student athletes that experience sudden cardiac death, who are too young to have developed heart disease," Garcia says. "We can screen athletes before they get into competitive sports. It is very inexpensive."
Three-Dimensional Echo: With 3-D echo, the cardiologist can obtain multiple ultrasound images of the heart's interior -- then assemble them into a complete image of the heart in motion, Steiner explains. "It allows us to view the heart anatomy in a different way -- to get all sorts of special images we couldn't get before."
3-D echo provides more accurate measurements of heart muscle function and a better view of heart valves than possible before, Garcia tells WebMD. "It also provides automatic measurement of heart muscle function. Rather than eyeball it, we can use computer analysis of how strong the heart muscle is contracting -- how strong blood is pumping."
The procedure is used to evaluate complex valve or congenital heart disease, he adds. "Because it is an emerging technology, we are still trying to define its clinical applications."
Intracardiac Echo: Echo is being used during cardiac cath procedures, Garcia says. "A small transducer is threaded through the catheter," he tells WebMD. "It's a way of taking echo into the heart, so we can use it as a guide during an interventional procedure - such as closing holes in the heart, ablating arrhythmias, or ballooning open a narrow valve. This ultrasound provides a more accurate image to monitor the procedure while it is being performed."