Inhaled prostacyclin, nitric oxide, and nitroprusside in pulmonary hypertension after mitral valve replacement.
OBJECTIVE
Pulmonary hypertension increases morbidity and mortality in patients undergoing heart surgery. Mitral valve stenosis is frequently associated with an increase in pulmonary vascular resistance (PVR). Cardiopulmonary bypass exacerbates pulmonary hypertension in patients undergoing cardiac surgery. The aim of this study was to compare the hemodynamic effects of inhaled prostacyclin and nitric oxide and the administration of i.v. nitroprusside during cardiac surgery with a clinical, pharmacodynamic dose-response, prospective, randomized, and double-blind study (Group A: inhaled prostacyclin; Group B: inhaled nitric oxide; Group C: nitroprusside).


METHODS
Fifty-eight patients with mitral valve stenosis and elevated PVR (>200 dynes sec/cm5) after mitral valve surgery were studied. Inhaled prostacyclin and nitric oxide were administered at concentrations of 10 g/min and 20 ppm, respectively. Nitroprusside i.v. was administered at the dose of 5-15 g/min.


RESULTS
Prostacyclin and nitric oxide produced a significant dose-related decrease of mean pulmonary arterial pressure, pulmonary vascular resistance, and transpulmonary gradient. A significant increase in cardiac output was observed in both groups. In Group C, nitroprusside administration was interrupted in 62% patients due to occurrence of systemic hypotension.


CONCLUSIONS
Inhaled prostacyclin and nitric oxide are effective in the treatment of postoperative pulmonary hypertension in patients with mitral valve stenosis undergoing mitral valve surgery. Both drugs improve cardiac output and reduce mean pulmonary arterial pressure, pulmonary vascular resistance, and trans-pulmonary gradient. They may be useful in patients with acute right ventricular failure following cardiac surgery. In comparison to nitric oxide, inhaled prostacyclin is free from toxic side effects and is easier to administer.
Fattouch
Khalil
K
Operative Unity of Cardiac Surgery, Università di Palermo "Paolo Giaccone", Palermo, Italy. khalilfat-touch@hotmail.com
Sbraga
Fabrizio
F
Bianco
Giuseppe
G
Speziale
Giuseppe
G
Gucciardo
Marco
M
Sampognaro
Roberto
R
Ruvolo
Giovanni
G
D000280:Administration, Inhalation; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects; D004311:Double-Blind Method; D045462:Endothelium-Dependent Relaxing Factors / Q000378:metabolism; D011464:Epoprostenol / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D008946:Mitral Valve Stenosis / Q000150:complications / Q000601:surgery*; D009569:Nitric Oxide / Q000008:administration & dosage / Q000627:therapeutic use*; D009599:Nitroprusside / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
D000959:Antihypertensive Agents; D045462:Endothelium-Dependent Relaxing Factors; D009599:Nitroprusside; D009569:Nitric Oxide; D011464:Epoprostenol