Three-dimensional endocardial impedance mapping: a new approach for myocardial infarction assessment. Wolf, Tamir, Lior Gepstein, Gal Hayam, Asaph Zaretzky, Rona Shofty, Dina Kirshenbaum, Gideon Uretzky, Uri Oron, and Shlomo A. Ben-Haim. 1Cardiovascular System Laboratory, Bruce Rappaport Faculty of Medicine, and 2Department of Cardiothoracic Surgery, Carmel Medical Center, Technion-Israel Institute of Technology, Haifa 31096; and 3Department of Zoology, Tel-Aviv University, Tel-Aviv, Israel
APStracts 7:0554H, 2000.
Precise identification of infarcted myocardial tissure is of importance in diagnostic and interventional cardiology. A three-dimensional, catheter-based endocardial electromechanical mapping technique was used to assess the ability of local endocardial impedance in delineating the exact location, size, and border of canine myocardial infarction. Electromechanical mapping of the left ventricle was performed in a control group (n = 10) and 4 wk after left anterior descending coronary artery ligation (n = 10). Impedance, bipolar electrogram amplitude, and endocardial local shortening were quanitified. The infarcted area was compared with the corresponding regions in controls, revealing a significant reduction in impedance values [infarcted vs. controls: 168.8 ± 11.7 and 240.7 ± 22.3 OMEGA, respectively (means ± SE), P < 0.05]. The accuracy of the impedance maps in delineating the location and extent of the infarcted region was demonstrated by the high correlation with the infarct area (Pearson's correlation coefficient = 0.942) and the accurate identification of the infarct borders in pathology. By accurately defining the myocardial infarction and its borders, endocardial impedance mapping may become a clinically useful tool in differentiating healthy from necrotic myocardial tissue. 

Received 28 January 2000; accepted in final form 23 August 2000
APS Manuscript Number H82-0.
Article publication pending Am J Physiol Heart Circ Physiol
ISSN 1080-4757 Copyright 2000 The American Physiological Society.
Published in APStracts on 20 October 2000