Impedance mapping of myocardial tissue during ischemia

Abstract

An impedance measurement system was developed for measuring myocardial tissue impedance (MTI) during ischemia in sheep and epicardial mapping system was developed that used a four electrode method with cardiac cycle gated and signal averaged measurements. After 60 minutes of ischemia, MTI increased by an average of 200% compared to non-ischemic tissue. A myocardial tissue model was developed which suggests that changes in MTI are primarily due to changes in cellular volume fraction.<>