BACKGROUND: Doctors use stethoscopes to listen to heartbeats, but the results depend largely on the physician's interpretation. Some heart irregularities can be difficult to detect, such as heart murmurs. Cardioscan is a new computer-assisted stethoscope device designed to help primary care physicians analyze the wide range of heart murmurs, to better understand which murmurs are pathological and which are not. Cardioscan is now being used on an introductory basis by primary care physicians at centers around the country. Cardioscan is portable, easy-to-use and non-invasive.
HOW IT WORKS: With Cardioscan, the sound of the heartbeat is displayed graphically in order to help the physician determine which valve in the heart a murmur may be coming from, and how serious it might be. Each reading is recorded and stored and could be used as a baseline for follow-up visits. Sound waves are mechanical energy. Passing a coil of wire through a magnetic field will generate electricity within that coil, while passing electricity through a coil of wire will give rise to a magnetic field. A transmitter (such as that in a telephone) contains both a wire coil and a small magnet. Sound waves cause the coil to vibrate in response to the sound waves within a magnetic field. This turns the sound wave into an electrical signal, which can be transmitted to a computer. This data is then used to produce the graphical image.
BENEFITS: A 2005 clinical study measured the accuracy of a group of primary care physicians in evaluating a set of 100 recorded sounds. The heart sounds were independently evaluated by each physician without consulting Cardioscan. Then they were evaluated again with Cardioscan. The physicians were able to reduce their rates of unnecessary referrals by an average of 41 percent. So Cardioscan has the potential to result in greatly reduced costs, because more than 3 million patients are unnecessarily referred each year for an echocardiogram to test for heart murmurs. The study also showed a 46 percent reduction in false negative rates, so Cardioscan could also help save lives by helping physicians detect dangerous heart conditions.