Kinetic analysis of rubidium and thallium as deposited myocardial
blood flow tracers in isolated rabbit heart.
Marshall, Robert C., Scott E. Taylor, Patricia Powers-Risius, Bryan W.
Reutter, Alvin Kuruc, Pamela G. Coxson, Ronald H. Huesman, and Thomas
F. Budinger.
E. O. Lawrence Berkeley National Laboratory, Center for Functional
Imaging, Berkeley, California 94720, Martinez Veterans
Administration, Northern California System of Outpatient Clinics,
Martinez, California 94553
APStracts 3:0459H, 1996.
Evaluation of myocardial perfusion with tracers such as thallium and
rubidium is based on the assumption that tissue tracer content is
proportional to flow. The purpose of this study was to evaluate the
relationship between flow and tissue tracer content of thallium-201
and rubidium-83 in the isolated perfused rabbit heart. Rubidium-83
(86 d half-life) , an isotope that is not used clinically, was used
as a subsitute for rubidium-82 (76 s half-life) in order to improve
the ac curacy and precision of data a cquisition. The multiple
indicator dilution technique was employed with two independent
computational approaches. The first approach explicitly deconvolved
thallium-201 and rubidium-83 venous concentration curves by the
intravascular reference tracer curve. The second approach used a
conventional analysis. Both approaches showed that there was more
early washout of rubidium-83 than thallium-201 and that the heart
retained thallium-201 better than rubidium-83 within 2 min after
isotope introduction. These data indicate that thallium-201 is a
better perfusion tracer than rubidium-83 in the isolated rabbit
heart.
Received 9 April 1996; accepted in final form 11 September 1996.
APS Manuscript Number H313-6.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996