Researchers have developed an experimental iPhone application, or app, designed to help emergency medical technicians diagnose a particularly deadly form of heart attack and send that information quickly to waiting hospital surgical teams. The inexpensive app can greatly improve a patient’s odds of survival.
The iPhone app is specially designed to identify patients suffering from a dangerous type of heart attack known as STEMI, or ST-elevation myocardial infarction.
In STEMI, blood flow to the heart is blocked by a clot in a coronary artery. Unlike many types of heart attacks, STEMIs show up very clearly on an electrocardiogram, or ECG, a diagnostic test that measures the heart’s electrical activity. Small adhesive wire leads are placed on the chest around the heart. They feed signals to the ECG, which prints a paper tracing of a dozen waves showing cardiac activity.
With the experimental iPhone app, emergency medical technicians responding to a call can do an ECG, snap an image of the tracing with the mobile phone camera and transmit it clearly at high speed over the cell network.
David Burt and his students at the University of Virginia in Charlottesville jointly developed the iPhone app. Burt says the app has the potential to save lives by alerting emergency room doctors to get ready for the STEMI patient, who will need catheterization and surgery to unblock the artery.
“A decision made as early as possible in the STEMI treatment process allows the system to ramp up or mobilize so that when the patient shows up, they are pushed into the “cath” [catheterization] lab, everything happens and their [coronary] artery gets opened [unblocked],” said Burt.
The iPhone app centers and reduces the size of the ECG image, sending a sharp, clear, easy-to-read image to waiting physicians in as little as four seconds. The developers tested the app 1,500 times over three U.S. cellular networks in an urban area. Normally, when emergency medical teams send an ECG image to the hospital by regular e-mail, it can take between 38 and 114 seconds – a long time when a patient’s life is at stake.
“If your iPhone at the time that you hit ‘send’ shows two or more bars, the app is successful in sending an image 94-plus percent of the time in less than 10 seconds,” he said.
Burt and his student developers are now testing the still-nameless app in rural areas, where cell phone reception is typically less reliable than in cities. They are hoping to make the software available at a very low cost.
The emergency iPhone app that quickly transmits diagnostic heart images was presented at an American Heart Association symposium in Baltimore, Maryland.