Improvement of cardiac performance by intravenous infusion of L-arginine in patients with moderate congestive heart failure.
OBJECTIVE
The aim of this study was to evaluate the hemodynamic effect of L-arginine infusion in patients with congestive heart failure.


BACKGROUND
Endothelium-dependent vasodilation is impaired in patients with congestive heart failure. Nitric oxide, which was identified as endothelium-derived relaxing factor, is generated by nitric oxide synthase from L-arginine. Our hypothesis was that administration of L-arginine in patients with congestive heart failure may increase nitric oxide production and have a beneficial hemodynamic effect.


METHODS
Twelve patients with congestive heart failure (New York Heart Association class II or III) due to coronary artery disease (left ventricular ejection fraction < 35%) were given 20 g of L-arginine by intravenous infusion over 1 h at a constant rate. Stroke volume, cardiac output and left ventricular ejection fraction were determined with Doppler echocardiography at baseline and at 30 and 60 min and 1 h after the end of infusion. Blood and urinary levels of nitrite/nitrate (NO2/NO3), stable metabolites of nitric oxide, were measured and clearance was calculated.


RESULTS
One hour of infusion of L-arginine resulted in a significant increase in stroke volume (from 68 +/- 18 ml to 76 +/- 23 ml [mean +/- SD], p = 0.014) and cardiac output (from 4.07 +/- 1.22 liters/min to 4.7 +/- 1.42 liters/min, p = 0.006) without a change in heart rate. Mean arterial blood pressure decreased (from 102 +/- 11 mm Hg to 89 +/- 9.5 mm Hg, p < 0.002), and systemic vascular resistance decreased significantly. Within 1 h after cessation of L-arginine infusion, blood pressure, stroke volume, cardiac output and systemic vascular resistance were statistically not different from baseline values. Clearance of NO2/NO3 increased significantly during L-arginine administration (from 13.28 +/- 0.42 ml/min to 29.97 +/- 1.09 ml/min, p < 0.001).


CONCLUSIONS
Infusion of L-arginine in patients with congestive heart failure results in increased production of nitric oxide, peripheral vasodilation and increased cardiac output, suggesting a beneficial hemodynamic and possibly therapeutic profile.
Koifman
B
B
Department of Cardiology, Tel Aviv Medical Center, Tel Aviv University, Israel.
Wollman
Y
Y
Bogomolny
N
N
Chernichowsky
T
T
Finkelstein
A
A
Peer
G
G
Scherez
J
J
Blum
M
M
Laniado
S
S
Iaina
A
A
D000368:Aged; D001120:Arginine / Q000008:administration & dosage / Q000627:therapeutic use*; D003327:Coronary Disease / Q000150:complications; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood; D009573:Nitrites / Q000097:blood
D009566:Nitrates; D009573:Nitrites; D001120:Arginine