Echocardiographic Molecular Imaging for POC Detection of Ischemia

Molecular imaging with myocardial contrast echocardiography (MCE) relies on the non-invasive detection of targeted microbubbles (MBs) or other acoustically active agents. The confinement of MBs to the vascular compartment makes them ideal for assessing acute inflammatory responses involving endothelial cell activation and immune cell recruitment. A construct for imaging inflammation and endothelial activation can be achieved by altering amphipathic lipid shell composition in MBs. Specifically, incorporation of phosphatidylserine (PS) into the shell of MBs promotes adhesion to activated leukocytes and endothelial cells which can be used to detect ischemia, whether active or resolved. Our first in human studies to use myocardial contrast echocardiography (MCE) to detect inflammation secondary to ischemia was performed with a PS-containing MB contrast agent (Sonazoid) where we studied patients with known acute coronary syndrome (ACS) who had just undergone acute percutaneous coronary intervention. In this study, we will conduct a proof-of-concept clinical trial where MCE molecular imaging with Sonazoid will be performed in 80 patients with suspected rather than known ACS. We will test whether MCE ischemic memory imaging with MB-PS can diagnose or exclude ACS, and assess risk based on spatial extent of signal enhancement.