Effect of Congestive Heart Failure on Disappearance of T-1824 From Plasma in Man

¹ From the Department of Medicine, The Johns Hopkins University and Hospital, Baltimore, Maryland

The possibility that congestive heart failure is accompanied by an unusually rapid leakage of T-1824 from the plasma has been investigated by comparing T-1824 disappearance curves in patients in congestive failure with those from patients in a state of cardiac compensation. Twenty-two studies were carried out on a total of 15 patients. Plasma concentrations of T-1824 were measured following a single rapid intravenous injection, including the initial dilution curve and multiple samples up to several days after injection. No evidence of such rapid leakage was found although it could not be ruled out during the 2- to 4-minute period. No significant difference between the disappearance rates during congestive heart failure and those during compensation was observed after the 4-minute sample. When congestive failure was relieved, the calculated plasma volume decreased in five out of six patients, and increased in one patient, with no significant change in disappearance rates. The peak concentration of the initial dilution curve was frequently lower in congestive failure than in compensation, but its correlation with the heart-lung-great vessel plasma volume was the same in both situations. No correlation was observed between cardiac output and early disappearance rate (2–10 min.). No significant difference between plasma volume calculated from a single 10-minute sample and that calculated by extrapolation from 30- to 60-minute samples was found. In nine patients data permitted graphic analysis of the disappearance curve into multiple exponential components. In five of these patients the results suggested either a relatively slow mixing phase or a relatively rapid extravascular transfer, in addition to the usual rapid intravascular mixing, extravascular transfer and degradation.