3D Real-Time Ultrasound Cardiac Mapping Technology Improves Accuracy and Patient Safety

A team of clinicians is the first in the United States to utilize new ultrasound technology to guide ablation of atrial fibrillation (AF), providing potential improvements in both the precision and safety of this therapy.

AF is the most common type of heart rhythm disorder. In treating AF with catheter ablation, cardiac electrophysiologists conventionally use standard X-ray technology to guide proper placement of radiofrequency energy to ablate the tissues (cause small areas of scarring) in the heart responsible for starting and maintaining the irregular rhythm. The clinicians, from Loyola University Health System (Maywood, IL, USA), also can generate a computer reconstruction of the heart's interior, frequently with the help of images obtained from either computed tomography (CT) or magnetic resonance imaging (MRI) scans done before the procedure. While helpful, these reconstructions can be time-consuming, difficult to produce, and expose patients to additional radiation.

With newly installed software imaging technology, the CartoSound image integration module and SoundStar 3D catheter, Loyola physicians now are able to visualize and create a whole new kind of map of the heart in order to perform atrial ablation. They use ultrasound imaging to produce images of the heart during the ablation procedure. The ultrasound technique produces three-dimensional (3D) images of the heart's anatomy within a few minutes at the bedside, and allows real-time, simultaneous monitoring of catheter position and orientation during the procedure, improving both precision and patient safety. Dr. David Wilber, professor of cardiovascular sciences at Loyola University Stritch School of Medicine, reported that he and his team have used the new technology with 20 patients giving "excellent results.” The technology was developed by Biosense Webster, Inc.(Diamond Bar, CA, USA), a Johnson & Johnson company.

Whereas the previous method provided 3D images of the heart, they frequently lacked sufficient detail. Incorporating CT images from a scan obtained several days earlier provided more detail, but it was difficult to accurately register the older image to the precise orientation of the heart during the procedure.

"The new 3D ultrasound images provide a very detailed view of the heart, and most importantly, they reflect the condition of the heart during the procedure. Since the image is generated by the same computer program that tracks the location of the catheter, the points of interest match very closely,” Dr Wilber explained. "This allows very accurate placement of lesions [the scarring] to assure elimination of the arrhythmia, while avoiding injury to important nearby structures, such as the pulmonary veins or the esophagus. We can now image these structures with unprecedented accuracy continuously during the procedure.”

Overall procedure time is decreased by more than 30 minutes, Dr. Wilber added, and the need for additional imaging procedures prior to ablation may be completely eliminated. "This is real breakthrough in making these procedures safer, more precise, and less taxing on the patient. We are extremely excited about being able to bring these benefits to patients here at Loyola,” Dr. Wilber said.

AF may be related to coronary artery disease, thyroid disease, high blood pressure, or other structural heart defects, but frequently has no detectable cause. If left untreated, AF can cause structural heart changes that diminish heart function.


Related Links:
Biosense Webster
Loyola University Health System