Cardiovascular effects of inhaled nitric oxide in patients with left ventricular dysfunction.
BACKGROUND
Pulmonary vascular resistance (PVR) is frequently elevated in patients with advanced heart failure. Nitric oxide (NO), which contributes to the activity of endothelium-derived relaxing factor, causes relaxation of pulmonary arteries and veins in vitro. Inhalation of NO gas causes pulmonary vasodilation in patients with primary and secondary forms of pulmonary hypertension.


RESULTS
To test the hypothesis that inhalation of NO gas lowers PVR in patients with heart failure, we studied the hemodynamic effects of a 10-minute inhalation of NO (80 ppm) in 19 patients with New York Heart Association class III (n = 5) and class IV (n = 14) heart failure due to left ventricular (LV) dysfunction. Although inhalation of NO had no effect on pulmonary artery pressures, the PVR decreased by 31 +/- 7% (P < .001) due to a 23 +/- 7% increase (P < .001) in pulmonary artery wedge pressure and despite a 4 +/- 2% (P < .05) decrease in cardiac index. The magnitude of the decrease in PVR with inhaled NO was inversely related (r = -.713; P < .001) to the baseline PVR. Inhaled NO had no effect on heart rate, systemic arterial pressure, systemic vascular resistance, or LV peak +dP/dt or -dP/dt.


CONCLUSIONS
In patients with heart failure due to LV dysfunction, inhalation of NO causes a decrease in the PVR associated with an increase in LV filling pressure. These findings predict that inhaled NO, if used alone at this dose (80 ppm), may have adverse effects in patients with LV failure.
Loh
E
E
Department of Medicine, Brigham and Women Hospital, Boston, MA 02115.
Stamler
J S
JS
Hare
J M
JM
Loscalzo
J
J
Colucci
W S
WS
D000280:Administration, Inhalation; D002319:Cardiovascular System / Q000187:drug effects*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000008:administration & dosage* / Q000627:therapeutic use; D011652:Pulmonary Circulation / Q000187:drug effects; D011669:Pulmonary Wedge Pressure / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects; D018487:Ventricular Dysfunction, Left / Q000188:drug therapy*; D016277:Ventricular Function, Left / Q000187:drug effects
D009569:Nitric Oxide