Metabolism of the human heart during myocardial infarction may be studied by means of arterial and coronary sinus catheterization at little risk, but definite inconvenience. Ischemia has been readily detected through myocardial production or release of lactate, potassium, hydrogen, and certain enzymes. These findings may be of help in identifying the presence of acute myocardial injury or infarction and in evaluation of applied therapy. Other studies, particularly of metabolized substrates, including oxygen, have been less rewarding. The patchy nature of coronary atherosclerosis and its partial compensation by collateral vessels renders coronary venous inflow nonuniform. This makes interpretation of the meaning of the concentration of substances contained within the coronary venous effluent extremely difficult. Multiple-site venous sampling is particularly helpful in overcoming this inherent defect in the method.
- © 1969 American Heart Association, Inc.