Spironolactone reduced arrhythmia and maintained magnesium homeostasis in patients with congestive heart failure.
BACKGROUND
Patients with congestive heart failure (CHF) often have increased aldosterone activity that leads to hypomagnesemia. Hypomagnesemia can induce arrhythmias, an important cause of death in patients with CHF. We determined whether the aldosterone receptor antagonist spironolactone improved magnesium homeostasis and reduced arrhythmias in patients with CHF.


RESULTS
We randomized 116 consecutive patients with CHF into placebo control group (n = 58) and spironolactone group (20 mg daily, n = 58) in addition to conventional therapy. Plasma magnesium concentration (PMC), erythrocyte magnesium concentration (EMC), and erythrocyte magnesium efflux were not different between the 2 groups of patients before treatment. Compared with control patients, patients treated with spironolactone for 6 months had increased PMC and EMC and decreased erythrocyte magnesium efflux. Patients on spironolactone therapy also had a marked decrease of 24-hour mean heart rate, ventricular and atrial premature beats, and the risk of atrial fibrillation/flutter. Pooled data from the 116 patients showed that patients with a higher EMC or a lower sodium-dependent erythrocyte magnesium efflux had a slower heart rate, fewer ventricular premature beats, and a lower risk of atrial fibrillation/flutter.


CONCLUSIONS
Our results suggest that reducing cellular magnesium efflux and loss may contribute to the spironolactone-reduced arrhythmias in patients with CHF.
Gao
Xiuren
X
Department of Cardiology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou 510080, China.
Peng
Longyun
L
Adhikari
Chandra M
CM
Lin
Jun
J
Zuo
Zhiyi
Z
D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000517:prevention & control*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004912:Erythrocytes / Q000378:metabolism; D017079:Exercise Tolerance / Q000187:drug effects; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000150:complications* / Q000188:drug therapy*; D006334:Heart Function Tests / Q000187:drug effects; D006706:Homeostasis / Q000187:drug effects; D006801:Humans; D008274:Magnesium / Q000097:blood; D008275:Magnesium Deficiency / Q000097:blood / Q000150:complications* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D000451:Mineralocorticoid Receptor Antagonists / Q000627:therapeutic use*; D011188:Potassium / Q000097:blood; D013148:Spironolactone / Q000627:therapeutic use*; D016896:Treatment Outcome
D000451:Mineralocorticoid Receptor Antagonists; D013148:Spironolactone; D008274:Magnesium; D011188:Potassium