Time course of improvement in left ventricular function, mass and geometry in patients with congestive heart failure treated with beta-adrenergic blockade.
OBJECTIVE
We examined the time course of ventricular functional improvement in patients with dilated cardiomyopathy who received beta-blockade and the long-term effects of beta-blockade on ventricular mass and geometry in these patients.


BACKGROUND
Previous studies have shown that beta-adrenergic blocking agents when administered long term improve ventricular function in patients with heart failure. However, the time course of improvement in ventricular function and the long-term effects of beta-blockade on ventricular mass and geometry are not known.


METHODS
Twenty-six men with dilated cardiomyopathy underwent serial echocardiography on days 0 and 1 and months 1 and 3 of either metoprolol (n = 16) or standard therapy (n = 10). At 3 months all patients on standard therapy were crossed over to metoprolol, and late echocardiograms were obtained after 18 +/- 5 (mean +/- SD) months of metoprolol therapy. All echocardiograms were read in blinded manner.


RESULTS
Patients treated with metoprolol had an initial decline (day 1 vs. day 0) in ventricular function (increase in end-systolic volume and decrease in ejection fraction). Ventricular function improved between months 1 and 3 (p = 0.013, metoprolol vs. standard therapy). Left ventricular mass regressed at 18 months (333 +/- 85 to 275 +/- 53 g, p = 0.011) but not at 3 months. Left ventricular shape became less spherical and assumed a more normal elliptical shape by 18 months (major/minor axis ratio 1.5 +/- 0.2 to 1.7 +/- 0.2, p = 0.0001).


CONCLUSIONS
Patients with heart failure treated with metoprolol do not demonstrate an improvement in systolic performance until after 1 month of therapy and may have a mild reduction in function initially. Long-term therapy with metoprolol results in a reversal of maladaptive remodeling with reduction in left ventricular volumes, regression of left ventricular mass and improved ventricular geometry by 18 months.
Hall
S A
SA
Echocardiography Laboratory, Dallas Veterans Administration Hospital, Texas.
Cigarroa
C G
CG
Marcoux
L
L
Risser
R C
RC
Grayburn
P A
PA
Eichhorn
E J
EJ
D000704:Analysis of Variance; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004452:Echocardiography; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008790:Metoprolol / Q000627:therapeutic use*; D008875:Middle Aged; D015588:Observer Variation; D013599:Systole / Q000502:physiology; D013997:Time Factors; D016277:Ventricular Function, Left / Q000187:drug effects*
D008790:Metoprolol