Effective control of refractory pulmonary hypertension after cardiac operations.
OBJECTIVE
Inhaled nitric oxide is a promising therapy to control pulmonary hypertension. However, pulmonary hypertension caused by valvular heart disease is often refractory to inhaled nitric oxide. The objective of this study was to determine whether the combination of inhaled nitric oxide plus dipyridamole will cause a response in patients with pulmonary hypertension undergoing cardiac operations who had not responded to inhaled nitric oxide alone.


METHODS
Responses in 10 patients (62 +/- 7 years) with pulmonary hypertension caused by aortic or mitral valvular disease (mean pulmonary artery pressure, > or = 30 mm Hg) were studied in the operating room after valve replacement. The effect of inhaled nitric oxide alone (40 ppm) on pulmonary vascular resistance, mean pulmonary artery pressure, cardiac output, and mean arterial pressure was determined. Inhaled nitric oxide administration was then stopped and patients were given dipyridamole (0.2 mg/kg intravenously); the effect of inhaled nitric oxide plus dipyridamole was then examined.


RESULTS
Dipyridamole effected a response in patients who had not responded to nitric oxide. Pulmonary vascular resistance and mean pulmonary artery pressure were significantly reduced and cardiac output was increased without change in mean arterial pressure.


CONCLUSIONS
Patients with refractory pulmonary hypertension in whom inhaled nitric oxide alone fails to cause a response may respond to combined therapy of inhaled nitric oxide plus dipyridamole. This therapy may be particularly valuable in patients with dysfunction of the right side of the heart as a result of pulmonary hypertension because of its effective lowering of right ventricular afterload.
Fullerton
D A
DA
Department of Surgery at Northwestern University, Chicago, Ill., USA.
Jaggers
J
J
Piedalue
F
F
Grover
F L
FL
McIntyre
R C
RC
D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D004176:Dipyridamole / Q000627:therapeutic use*; D004338:Drug Combinations; D006349:Heart Valve Diseases / Q000601:surgery*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D008875:Middle Aged; D009569:Nitric Oxide / Q000627:therapeutic use*; D011183:Postoperative Complications / Q000188:drug therapy*; D011651:Pulmonary Artery / Q000502:physiology; D016896:Treatment Outcome; D014655:Vascular Resistance / Q000187:drug effects; D014665:Vasodilator Agents / Q000627:therapeutic use*
D004338:Drug Combinations; D014665:Vasodilator Agents; D009569:Nitric Oxide; D004176:Dipyridamole