Myocardial extraction of Rb86 in the rabbit

Abstract

An investigation of the myocardial extraction of Rb⁸⁶ was carried out using the Langendorff preparation in the isolated rabbit heart. Extraction was found to be related exponentially to both the rate of flow and the length of time of the flow. In the determination of coronary blood flow based upon the myocardial uptake of Rb⁸⁶, an average value for myocardial extraction must be assumed in order to avoid coronary sinus catheterization. The data in these rabbit experiments suggest that when coronary blood flow is increased or decreased 50% the error which results from assuming a constant value for myocardial extraction is of the order of 20%.