Digoxin withdrawal in patients with dilated cardiomyopathy following normalization of ejection fraction with beta blockers.
BACKGROUND
The effect of withdrawal of digoxin on left ventricular function in patients with a history of idiopathic dilated cardiomyopathy (IDCM) following normalization of left ventricular ejection fraction (LVEF) with beta blockers remains unknown.


OBJECTIVE
This study was undertaken to determine the effect of digoxin withdrawal on left ventricular function in patients with IDCM.


METHODS
In 8 consecutive patients with IDCM (5 men, 3 women) who had normalization of LVEF following beta-blocker treatment, digoxin was withdrawn as part of an office protocol. and LVEF was followed. Baseline EF prior to beta blocker initiation (carvedilol = 6, atenolol = 1, metoprolol 1) was measured with isotope ventriculography (IVG), echocardiography, or left ventriculography. Post beta blocker ejection fraction (post BB EF) was measured in all patients with IVG at a mean of 17.25 +/- 5.38 months. Follow-up EF was measured using IVG after digoxin withdrawal at a mean of 6.99 +/- 4.34 months.


RESULTS
An experienced blinded reader interpreted the IVG scans. Baseline EF was 28.5 +/- 8.26; post BB EF and follow-up EF were 56.1 +/- 4.65 and 51.0 +/- 7.35, respectively (p = 0.05).


CONCLUSIONS
These data provide potential evidence that digoxin withdrawal can result in a small but significant reduction in LVEF in patients with IDCM who had normalization of LVEF after treatment with beta blockers. Mean LVEF, however, remained within normal (> 50%) on beta-blocker therapy and without digitalis. Large, randomized controlled trials are needed to confirm these findings.
Shammas
N W
NW
Genesis Heart Institute and Cardiovascular Medicine, PC, Davenport, Iowa 52803, USA. shammas@home.com
Harris
M L
ML
McKinney
D
D
Hauber
W J
WJ
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D002311:Cardiomyopathy, Dilated / Q000188:drug therapy* / Q000503:physiopathology; D004077:Digoxin / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume / Q000187:drug effects; D016277:Ventricular Function, Left / Q000187:drug effects*
D000319:Adrenergic beta-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D004077:Digoxin