title: Pulmonary vascular reactivity and prognosis in patients with chronic thromboembolic pulmonary hypertension: a pilot study.
abstract: BACKGROUND
  Surgical pulmonary endarterectomy is the preferred treatment for chronic thromboembolic pulmonary hypertension. Persistent pulmonary hypertension after pulmonary endarterectomy has been recognized as a major determinant of poor outcome. We tested whether acute vasoreactivity identifies chronic thromboembolic pulmonary hypertension patients prone to develop persistent/recurrent pulmonary hypertension after pulmonary endarterectomy and whether the degree of acute vasoreactivity affects survival or freedom from lung transplantation.
  
  
  RESULTS
  Right-sided heart catheterization at baseline and after inhalation of 40 ppm nitric oxide for 20 minutes was performed in 103 patients (56.3+/-15.3 years old, 53 women). Reductions in mean pulmonary arterial pressure (DeltamPAP; -8.8+/-12.6%; P<0.0001) and pulmonary vascular resistance (-16.1+/-18.1%; P<0.0001) and an increase in mixed venous saturation during inhaled nitric oxide (9.1+/-11.6%; P<0.0001) were observed. Sixty-two patients underwent pulmonary endarterectomy after a median of 49 days (25th and 75th percentiles: 24 and 123 days). Operated patients were followed up for a median of 70.9 months (25th and 75th percentiles: 14 and 97 months). Change in mPAP during inhaled NO was identified as a predictor of persistent/recurrent pulmonary hypertension after pulmonary endarterectomy. Patients experiencing a reduction in mPAP >10.4% with nitric oxide inhalation had a better postoperative outcome. A significant correlation was found between DeltamPAP and immediate postoperative pulmonary vascular resistance (r=0.5, P<0.0001).
  
  
  CONCLUSIONS
  A total of 80 (77.7%) of 103 patients demonstrated acute pulmonary vascular reactivity of some degree. A decrease in mPAP >10.4% under inhaled nitric oxide is a predictor of long-term survival and freedom from lung transplantation in adult patients with chronic thromboembolic pulmonary hypertension who are undergoing pulmonary endarterectomy.
authors.affiliation: Department of Internal Medicine II, Division of Cardiology, Vienna General Hospital, Medical University of Vienna, Vienna, Austria.
authors.forename: Nika
authors.initials: N
authors.lastname: Skoro-Sajer
authors.forename: Niklas
authors.initials: N
authors.lastname: Hack
authors.forename: Roela
authors.initials: R
authors.lastname: Sadushi-Koliçi
authors.forename: Diana
authors.initials: D
authors.lastname: Bonderman
authors.forename: Johannes
authors.initials: J
authors.lastname: Jakowitsch
authors.forename: Walter
authors.initials: W
authors.lastname: Klepetko
authors.forename: Mir Ali Reza
authors.initials: MA
authors.lastname: Hoda
authors.forename: Meinhard P
authors.initials: MP
authors.lastname: Kneussl
authors.forename: Peter
authors.initials: P
authors.lastname: Fedullo
authors.forename: Irene M
authors.initials: IM
authors.lastname: Lang
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D002908:Chronic Disease; D004691:Endarterectomy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000008:administration & dosage; D010865:Pilot Projects; D011379:Prognosis; D013923:Thromboembolism / Q000175:diagnosis* / Q000503:physiopathology* / Q000601:surgery; D014655:Vascular Resistance / Q000502:physiology*
chemical_list: D009569:Nitric Oxide