Surgical Heart Monitoring Goes High Tech

Transesophageal Echo device aids cardiac patients

/ Author:  / Reviewed by: Joseph V. Madia, MD

Medical technology is moving at the speed of light and this time it's heart patients who will reap the benefits. A new type of 3D monitoring used during cardiac procedures will enable surgeons to improve their precision.

This in turn may reduce a patient's chance of reoperation.

Currently 2D monitoring is the standard of care for most hospitals and medical facilities when it comes to certain heart operations in which the technology is used such as valve repairs.

The live 3D technology, which provides a view of cardiac structure and function and real-time displays of the beating heart, is utilized at very few facilities and is often still used mostly in research settings. A larger number have started using the 3D technology, but only a small percentage of those have adopted the live aspect.

“With a 3D image of the heart, surgeons and anesthesiologists can see the complete valve from multiple perspectives while it is beating, allowing us to have a comprehensive plan in place even before the first incision,” said Dr. Daniel Berson, D.O., an anesthesiologist at the Heart Hospital of Austin, one of a handful of facilities offering the live 3D technology.

“This also enables the surgeon to assess procedure outcomes and function before closing the chest and, if needed, further repairs can be done immediately.”

How does it work?

The Live 3D Transesophageal Echo (TEE) provides real-time 3D images through ultrasound waves that allows surgeons to better visualize heart repairs. While the technology can be used for many types of procedures, the Heart Hospital of Austin primarily uses TEE for valve repairs, aneurysms, aorta repairs and bypass surgery, though that list is expected to be expanded to include procedures such as trans arterial valve replacements.

Much like its 2D counterpart, a small probe is inserted into a patient's throat and down the esophagus. There is very little risk with the procedure, though a small percentage of patients who have difficulty swallowing could have trouble with the device.

"We can get great views of the heart," Dr. Berson said. "On a two-dimensional look we have to take images and the doctor has to recreate that image in his mind. Three dimensions hopefully gives the patient a better outcome."

The TEE provides information about the size and shape of the heart, and how the heart chambers and valves are working. It also can identify poor blood flow and also provides doctors with a view inside the left ventricle.

Because the 2D version also was not available live, doctors would have to stop to take the images and sometimes piece several together to create the full picture. The live technology allows the physicians the ability to keep going without the extra step of pausing to study images.

During TEE, a device called a transducer sends sound waves to the heart. As the ultrasound waves bounce off the structures of the heart, a computer inside the echo machine converts them into images on a screen.

How does it benefit patients?

Three-dimensional views are also easier to understand for patients and families. The view is clearer, families can more easily comprehend the problem, and patients can even see their own heart in action.

Additionally, the 3D technology is also useful following surgery such as after the repair of a valve. If there was a small leak, it could be difficult to see in two dimensions, whereas in 3D the problem could be precisely pinpointed and repaired immediately.

"The patient will not know anything differently, but the overall image quality and preciseness will decrease the amount of reoperation. Overall the more information you have, the better you can perform the surgery," Dr. Berson said. "It was more of a leap of faith when using 2D images. Now we can see a depth to it and rotate it on the screen."

Patients also benefit from the better precision afforded doctors when they have a complete view and can map out an entire surgery before it even begins.

“These visualizations give us amazingly clear pictures of the heart and on-the-spot evaluation,” said Dr. Stephen J. Dewan, M.D., F.AC.S., a surgeon with Cardiothoracic and Vascular Surgeons. “With a live 3D picture, we can more effectively determine the best treatment plan for patients, as well as more accurately repair the heart. This significantly lowers the chances a patient will need to be readmitted later on for further repairs.”

So, why isn't it used more?

Though the new technology is an asset to surgeons, few medical facilities offer live TEE. The major reason its use remains low is because many physicians have not yet been trained to use the device or certified. So many specialties in anesthesiology are now available that holding such certification has become a specific niche.

In addition to his board certification in anesthesiology by the American Board of Anesthesiology, Dr. Berson is also certified in perioperative transesophageal echocardiography by the National Board of Echocardiography. Currently, a relatively low number of doctors have elected to complete this specialty certification in echocardiology, which means some hospitals may simply avoid bringing in such new technology for the time being.

"The barrier is getting more ananesthesiologists board certified in this," Dr. Berson said. "We have four certified at my hospital and do about 500 hearts a year. We've done 300 echos in a two-year period. But some only do 10 to 20 hearts and don't get expertise in this field."

Reviewed by: 
Review Date: 
June 24, 2011