In vivo determination of time-dependent acute myocardial ischemia based on photoacoustic imaging

The location and ischemia extent are two important parameters for evaluating the acute myocardial ischemia (AMI). We explored the feasibility of using a focused transducer-based photoacoustic imaging to assess time-dependent AMI. Our preliminary results showed that photoacoustic signal could identify the myocardium. The intensity and area of photoacoustic images of myocardium could be used for characterizing the ischemia extent and scope of myocardial ischemia. The intensity of photoacoustic signal decreased with the increase of delaying time after LAD occlusion. This was because the increase of delaying time after LAD occlusion could reduce the blood supply to the myocardium and the blood volume in the myocardium. These results were consistent with the clinical characteristics. The finding suggests that photoacoustic imaging has a potential for the real-time assessment of acute myocardial ischemia during surgical operation.