Researchers are testing another diagnostic technique for detecting heart attacks, called body surface mapping. William Brady, M.D., Emergency Physician at the University of Virginia School of Medicine, explains the standard EKG uses 12 leads (electrodes with wires) that are placed over various points of the chest. The leads pick up electrical activity in the corresponding areas of the heart muscle. Body surface mapping uses many more leads, as many as 80 or more, to record electrical activity from the front, sides and back of the body.
Brady is testing a body surface mapping system, called PRIME Electrocartography® (Heartscape Technologies, Inc.). The wearable portion of the device is composed of 11 strips of leads placed over the body like a vest. The strips contain a total of 80 leads that record the heart’s electrical activity. The placement of leads around the upper torso enables doctors to monitor the electrical impulses in the heart from 360-degrees.
The strips can be placed on the body in about 15 to 20 minutes. Once in place, the system simultaneously records the electrical activity detected by all 80 leads. The information is fed to a computer that can show the EKG on a screen. The software also enables the physician to create a 3-D animation of the torso. The image can be rotated and areas of abnormal electrical activity can be more precisely pinpointed. The physician can use the computer’s mouse to select and highlight the EKG activity from a single lead. The information may also be used to monitor the patient and watch for signs of an “evolving” heart attack (based on electrical changes).
Preliminary research suggests the 80-lead technology may be better at detecting heart attack than the standard 12-lead EKG. The system can also help doctors find the location of an area of blockage in the artery. The PRIME Electrocartography is currently in clinical trials comparing it to standard EKG testing. The study is called OCCULT-MI (Optimal Cardiovascular Diagnostic Evaluation Enabling Faster Treatment of Myocardial Infarction). For information log onto the company’s website at http://www.heartscape.com.