title: Incidence of pleural effusions in idiopathic and familial pulmonary arterial hypertension patients.
abstract: BACKGROUND
  Pleural effusion occurs often in patients with left heart failure. There are no large-scale clinical studies investigating the incidence of pleural effusion in patients with right heart failure (RHF) alone.
  
  
  OBJECTIVE
  To determine the incidence of pleural effusions in patients with idiopathic pulmonary arterial hypertension (IPAH) and familial pulmonary arterial hypertension (FPAH).
  
  
  METHODS
  Consecutive IPAH and FPAH patients who were treated at Vanderbilt University Medical Center were retrospectively studied. Pleural effusions were detected by chest radiograph, chest CT scan, ultrasound, or autopsy.
  
  
  RESULTS
  Thirty-one of 147 patients (21.1%) with IPAH (128 patients) or FPAH (19 patients) had pleural effusions. Ten patients had explanations for the pleural effusions other than RHF. Two patients had no obvious explanations. The remaining 19 patients had RHF. When compared with the patients without pleural effusions, the patients with pleural effusions due to RHF had significantly higher mean right atrial pressure (16.0 +/- 6.8 vs 8.8 +/- 5.5 mm Hg, respectively; p < 0.001). There was no significant difference in other hemodynamic parameters between the two patient groups. The majority of effusions due to RHF are trace to small (63.2%) and right sided (57.9%) or bilateral (26.3%). Of the 19 patients with pleural effusions due to RHF, 8 patients had ascites, and 1 patient had moderate pericardial effusion. Four of the five patients who underwent thoracentesis had transudates.
  
  
  CONCLUSIONS
  Our study in IPAH and FPAH patients demonstrates that pleural effusions frequently occur in patients with isolated RHF.
authors.affiliation: Department of Pulmonary Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, People's Republic of China; Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN. Electronic address: tangkejing@gmail.com.
authors.forename: Ke-Jing
authors.initials: KJ
authors.lastname: Tang
authors.affiliation: Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN.
authors.forename: Ivan M
authors.initials: IM
authors.lastname: Robbins
authors.affiliation: Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Nashville, TN.
authors.forename: Richard W
authors.initials: RW
authors.lastname: Light
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D002648:Child; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology*; D012189:Retrospective Studies; D018709:Statistics, Nonparametric