title: Evaluation of pulmonary hypertension and surgical outcome by dynamic pulmonary perfusion imaging in patients with valvular disease.
abstract: OBJECTIVE
  The gold standard for assessing the degree of pulmonary hypertension is by right ventricular catheterization, an invasive procedure. This study was carried out to evaluate a noninvasive method using dynamic pulmonary perfusion imaging (DPPI) for assessing pulmonary hypertension and surgical outcome in patients with valvular heart disease.
  
  
  METHODS
  A total of 116 patients (50 men, 66 women, mean age: 45.8 ± 10.7 years) with valvular disease and 10 healthy volunteers (4 men, 6 women; mean age: 40.2 ± 12.8 years) were included in this study. Baseline DPPI with Tc-99m macroaggregated albumin and right ventricular catheterization were performed in all patients, before mitral valve replacement with or without aortic valve replacement surgery, and healthy volunteers. At 7 to 14 days postsurgery, 105 patients were re-evaluated with DPPI. A total lung region of interest was used to calculate a time-activity curve from the DPPI. The lung equilibrium time (LET: time from Tc-99m macroaggregated albumin entering the lungs to equilibrium) was measured. Receiver operating characteristic analysis of LET for diagnosing pulmonary hypertension was carried out.
  
  
  RESULTS
  LET in patients with valvular heart disease was significantly prolonged compared with those in 10 healthy volunteers (P < 0.001). LET was 14.79 ± 4.37 seconds and 27.78 ± 10.26 seconds in 10 healthy volunteers and patients, respectively). A strong correlation between LET and mean pulmonary arterial pressure (r = 0.827, P < 0.001) was found. Using mean pulmonary arterial pressure as a gold standard and threshold value of LET at 22.7 seconds, the sensitivity and specificity of LET for assessing pulmonary hypertension were found to be 94.7% and 78.0%, respectively. The pre- and postsurgery LET were found to be significantly different (27.48 ± 9.83 seconds vs. 21.33 ± 6.18 seconds, P < 0.001).
  
  
  CONCLUSIONS
  DPPI is an accurate and noninvasive method for evaluating pulmonary hypertension and surgical outcome in patients with valvular heart disease.
authors.affiliation: Department of Nuclear Medicine, Affiliated Hospital of Inner Mongolia Medical University, Huhehaote, China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Wang
authors.forename: Rongfang
authors.initials: R
authors.lastname: Shi
authors.forename: Shiwei
authors.initials: S
authors.lastname: Pan
authors.forename: Wei
authors.initials: W
authors.lastname: Fang
mesh_terms: D000328:Adult; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications* / Q000601:surgery*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications* / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008168:Lung / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D055420:Perfusion Imaging / Q000379:methods*; D013668:Technetium Tc 99m Aggregated Albumin; D016896:Treatment Outcome
chemical_list: D013668:Technetium Tc 99m Aggregated Albumin