Erythrocyte Na+, K+-ATPase activity in patients with congestive heart failure.
In order to determine if the Na+, K+-ATPase activity in erythrocyte membranes is altered in congestive heart failure, and to examine its clinical significance with respect to other clinical variables, erythrocyte Na+, K+-ATPase activity was measured in 51 patients with left ventricular ejection fractions <40% (coronary artery disease, n=26; dilated cardiomyopathy, n=25) and 24 control patients. Na+, K+-ATPase activity was lower in both coronary artery disease and dilated cardiomyopathy groups than control group even in the absence of digitalis use. There was a significant inverse correlation between Na+, K+-ATPase activity and plasma norepinephrine. The presence of non-sustained ventricular tachycardia was associated with a lower Na+, K+-ATPase activity in both groups with congestive heart failure without digitalis use than those without ventricular tachycardia. Plasma norepinephrine was higher in patients with non-sustained ventricular tachycardia than those without in the coronary artery disease group, but not in the dilated cardiomyopathy group. Na+, K+-ATPase activity may be helpful in predicting electrophysiologic instability in patients with heart failure.
Baba
A
A
Cardiopulmonary Division, Department of Medicine, Keio University School of Medicine, Tokyo, Japan.
Yoshikawa
T
T
Mitamura
H
H
Ogawa
S
S
D000328:Adult; D000367:Age Factors; D000368:Aged; D001706:Biopsy; D002311:Cardiomyopathy, Dilated / Q000097:blood / Q000150:complications / Q000201:enzymology*; D016022:Case-Control Studies; D003327:Coronary Disease / Q000150:complications / Q000201:enzymology; D004910:Erythrocyte Membrane / Q000201:enzymology*; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000150:complications / Q000201:enzymology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D017180:Tachycardia, Ventricular / Q000209:etiology
D000254:Sodium-Potassium-Exchanging ATPase; D009638:Norepinephrine