Water and Electrolytes in Congestive Failure 289 



balance studies, and by analyses of muscle biopsies, that in 

 addition to the cellular loss of potassium there is an incre- 

 ment of sodium in cells (Iseri, Boyle and Myers, 1950; Iseri 

 et aL, 1952; Squires, Crosley and Elkinton, 1951a; Warner 

 et aL, 1952; Cort and Matthews, 1954; see also Elkinton and 

 Danowski, 1955; Cort and Fencl, 1957). Particularly im- 

 portant is the fact that potassium depletion occurs in subjects 

 treated by repeated injections of mercurial diuretics (Squires 

 et al., 19516; Cort and Matthews, 1954). In some of these 

 severely ill cases hyponatraemia and hypochloraemia with an 

 elevated concentration of bicarbonate may be observed. 



Clinical diagnosis of potassium depletion in chronic conges- 

 tive failure is difficult to prove. Decompensated cardiacs 

 excrete negligible amounts of sodium and the stronger acid 

 radicals are excreted neutralized by potassium. Therefore 

 the typical finding of a far higher concentration of potassium 

 than sodium in the urine in congestive failure is not alone 

 sufficient proof of cellular loss of potassium. 



Plasma levels of Na+, K+, and Cl~ are usually within the 

 normal range in decompensated cardiac patients. 



Table I presents the relationship between plasma levels 

 of Na+, K+ and HCOa" and concentration of Na+ and K+ in 

 muscle biopsy specimens in 13 patients with various degrees 

 of heart failure. Concentrations of total muscle Na+ and K+ 

 are expressed in m-equiv. 100 g. of fat-free dry solids (FFDS). 

 Normal values given by Cort (1955b) are about 13 i 2 m-equiv. 

 of Na+ and 45 ± 3 m-equiv. of K+. 



It will be seen that all the patients had a decreased amount 

 of potassium in skeletal muscle. This K+ depletion was very 

 marked, although not all were treated with mercurial diu- 

 retics. Patient M.E. was not yet in right-sided failure. In all 

 patients, with the exception of A.Z., the plasma concentra- 

 tions of Na+ and K+ were within the normal range. In 

 the majority the concentration of bicarbonate was slightly 

 elevated. None of them showxd ECG changes typical of 

 potassium depletion. 



The lowest figure of muscle potassium (11 '2 m-equiv./lOOg.) 



AGEING — IV— 10 



