The Guardian, an implantable device being developed by AngelMed that alerts high-risk patients when they show signs of a heart attack, could shorten the time it takes for the wearer to seek medical attention.

To detect problems with blood flow in the heart, the device detects “segment elevation,” which causes an abnormality in the electrical current during the time that the heart is recharging between beats. It generates a buzz that the patient can feel on the skin. A receiver outside the body, which wirelessly receives data from the implant, then tells the patient if the problem is severe–meaning he needs to go to the hospital immediately.