Characterization of the “border zone” in acute regional ischemia in the dog

• Published in: The American journal of cardiology Vol. 40; no. 5; pp. 716 - 726
• Main Authors: Hearse, David J., Opie, Lionel H., Katzeff, Issy E., Lubbe, Willem F., Van Der Werff, Terry J., Peisach, Max, Boulle, Gerrard
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-11-1977
• Subjects: Adenosine Triphosphate - metabolism; Animals; Coronary Circulation; Coronary Disease - metabolism; Coronary Disease - pathology; Coronary Vessels - surgery; Dogs; Electrocardiography; Female; Glycogen - metabolism; Lactates - metabolism; Ligation; Male; Microspheres; Myocardium - metabolism; Myocardium - pathology; Phosphocreatine - metabolism; Potassium - metabolism; Sodium - metabolism
• ISSN: 0002-9149; 1879-1913
• DOI: 10.1016/0002-9149(77)90187-4

A biopsy instrument with multiple drill heads was used to retrieve simultaneously, and freeze within seconds, 29 individual transmural tissue samples from the left ventricular wall of the dog heart. Studies were undertaken 21 to 26 minutes after coronary arterial ligation to define the border zone between ischemic and nonischemic tissue using the following criteria: (1) metabolic changes (adenosine triphosphate, creatine phosphate, glycogen, lactate, potassium, sodium, water); (2) electro-cardiographic S-T changes; and (3) blood flow distribution (microspheres). The existence, position and sharpness of the gradients for each variable were defined in relation to the edge of the visible area of cyanosis. Adenosine triphosphate, creatine phosphate and lactate values in the nonischemic tissue were essentially constant until 2 to 3 mm from the edge of visible cyanosis. The high energy phosphate content of the tissue then decreased sharply across a zone 8 to 15 mm wide that spanned the visible edge. Across this zone lactate content increased sharply as did S-T segment elevation, and coronary flow decreased to approximately 20 percent of the control value. Multiple cross-correlation studies revealed that changes in the tissue content of adenosine triphosphate, creatine phosphate and lactate were accurately reflected by S-T segment changes, and further that all of these variables were directly related to the degree of ischemia, as indicated by the reduction in coronary flow. In addition to confirming the existence of a clearly defined border zone, these studies suggest that therapeutic salvage of this zone could considerably influence the extent of the ultimate infarct.