Efficacy of carvedilol treatment on cardiac function and cardiac sympathetic nerve activity in patients with dilated cardiomyopathy: comparison with metoprolol therapy.
Carvedilol and metoprolol have been reported to be effective in the treatment of patients with chronic heart failure. However, to our knowledge, there have been no studies comparing the effects of the 2 drugs on cardiac function, including cardiac sympathetic nerve activity.


METHODS
We compared 15 patients with dilated cardiomyopathy (DCM) who were receiving carvedilol (group A) with 15 patients with DCM who were receiving metoprolol (group B). Before and after 1 y of treatment, cardiac (123)I-metaiodobenzylguanidine ((123)I-MIBG) uptake was assessed using the total defect score (TDS) and the heart-to-mediastinum (H/M) activity ratio from the delayed images. The New York Heart Association (NYHA) class and echocardiographic left ventricular ejection fraction (LVEF) also were assessed.


RESULTS
In both groups, the TDS decreased (in group A, from 25 +/- 14 to 16 +/- 14, P < 0.01; in group B, from 27 +/- 9 to 19 +/- 10, P < 0.01), the H/M increased (in group A, from 1.67 +/- 0.31 to 2.01 +/- 0.36, P < 0.01; in group B, from 1.68 +/- 0.21 to 1.93 +/- 0.32, P < 0.01), the LVEF increased (in group A, from 31% +/- 10% to 48% +/- 10%, P < 0.01; in group B, from 28% +/- 9% to 47% +/- 15%, P < 0.01), and the NYHA functional class improved (in group A, from 2.9 +/- 0.3 to 1.7 +/- 0.5, P < 0.01; in group B, from 2.8 +/- 0.6 to 1.7 +/- 0.6, P < 0.01). The change in LVEF was mildly correlated with the change in the TDS in group A (r = 0.41) as well as in group B (r = 0.53). In the patients with a favorable response in the TDS or H/M, the NYHA class improved more than in the patients without a favorable response (P < 0.05).


CONCLUSIONS
Carvedilol treatment can improve cardiac function, symptoms, and cardiac sympathetic nerve activity in patients with DCM to a similar extent as metoprolol treatment. The improvement of cardiac function and symptoms is related to the improvement of cardiac sympathetic nerve activity.
Toyama
Takuji
T
Gunma Prefectural Cardiovascular Center, Maebashi, Japan. toyama.t@cvc.pref.gunma.jp
Hoshizaki
Hiroshi
H
Seki
Ryotaro
R
Isobe
Naoki
N
Adachi
Hitoshi
H
Naito
Shigeto
S
Oshima
Shigeru
S
Taniguchi
Koichi
K
D019797:3-Iodobenzylguanidine; D018674:Adrenergic Antagonists / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D002227:Carbazoles / Q000008:administration & dosage*; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D000077261:Carvedilol; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000187:drug effects / Q000294:innervation; D006801:Humans; D008297:Male; D008790:Metoprolol / Q000008:administration & dosage; D008875:Middle Aged; D011412:Propanolamines / Q000008:administration & dosage*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013564:Sympathetic Nervous System / Q000000981:diagnostic imaging* / Q000187:drug effects*; D017256:Technetium Tc 99m Sestamibi; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000209:etiology
D018674:Adrenergic Antagonists; D002227:Carbazoles; D011412:Propanolamines; D019275:Radiopharmaceuticals; D000077261:Carvedilol; D019797:3-Iodobenzylguanidine; D017256:Technetium Tc 99m Sestamibi; D008790:Metoprolol