An implantable medical device that includes an elongated lead body having an outer surface and an opening along the outer surface, a first sensor positioned along the lead body and configured to receive acoustic signals through the opening of the first lead body and generate an electrical signal representative of sounds produced at a targeted location along a patients cardiovascular system, and a processor configured to detect change in an S-T segment of sensed cardiac signals, and receive the acoustic signal and determine whether the sensed cardiac signals correspond to one of acute myocardial infarct and myocardial ischemia in response to the detected change.