title: Evaluation of the Microcirculation in Chronic Thromboembolic Pulmonary Hypertension Patients: The Impact of Pulmonary Arterial Remodeling on Postoperative and Follow-Up Pulmonary Arterial Pressure and Vascular Resistance.
abstract: BACKGROUND
  Chronic thromboembolic pulmonary hypertension (CTEPH) is generally recognized to be caused by persistent organized thrombi that occlude the pulmonary arteries. The aim of this study was to investigate the characteristics of small vessel remodeling and its impact on the hemodynamics in CTEPH patients.
  
  
  RESULTS
  Hemodynamic data were obtained from right heart catheterization in 17 CTEPH patients before pulmonary endarterectomy (PEA). Lung tissue specimens were obtained at the time of PEA. Pathological observations and evaluation of quantitative changes in pulmonary muscular arteries and veins were performed using light microscopy on 423 slides in 17 patients. The relationship between the results and the hemodynamics of CTEPH was investigated. Pulmonary arteriopathy and venopathy were recognized in most cases, although no plexiform lesions and no capillary-hemangiomatosis-like lesions were detected in any of the specimens. The severity of pulmonary arteriopathy was correlated with pulmonary vascular resistance (PVR) in the postoperative and follow-up periods. The PVR and mean pulmonary arterial pressure were significantly higher in the high-obstruction group than in the low-obstruction group. The findings in pulmonary venopathy were similar to the findings seen in pulmonary veno-occlusive disease in some cases, although severe venopathy was only observed in a portion of the pulmonary veins. There was a significant correlation between the extent of pulmonary arteriopathy and venopathy, although an effect of pulmonary venopathy to hemodynamics, including pulmonary arterial wedged pressure (PAWP), could not be identified.
  
  
  CONCLUSIONS
  The vascular remodeling of the pulmonary muscular arteries was closely associated with the hemodynamics of CTEPH. Severe pulmonary arteriopathy might be related to residual pulmonary hypertension after PEA. Those altered pulmonary arteries might be a new target for the persistent PH after the operation.
authors.affiliation: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba, 260-8670, Japan; Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Jujo
authors.affiliation: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Sakao
authors.affiliation: Department of Pathology, National Cerebral and Cardiovascular Center, 5-7-1, Fujishiro-Dai, Suita City, Osaka, 565-8565, Japan.
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
authors.affiliation: Department of Cardiovascular Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ishida
authors.affiliation: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Naito
authors.affiliation: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Sugiura
authors.affiliation: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba, 260-8670, Japan; Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Shigeta
authors.affiliation: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba, 260-8670, Japan; Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Tanabe
authors.affiliation: Department of Cardiovascular Surgery, Chiba Medical Center, National Hospital Organization, 4-1-2, Tsubakimori, Chuo-ku, Chiba, 260-8606, Japan.
authors.forename: Masahisa
authors.initials: M
authors.lastname: Masuda
authors.affiliation: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba, 260-8670, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Tatsumi
mesh_terms: D000368:Aged; D062186:Arterial Pressure / Q000502:physiology*; D001160:Arterioles / Q000473:pathology / Q000503:physiopathology; D002908:Chronic Disease; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006976:Hypertension, Pulmonary / Q000503:physiopathology* / Q000601:surgery*; D007150:Immunohistochemistry; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D015999:Multivariate Analysis; D011182:Postoperative Care; D011651:Pulmonary Artery / Q000473:pathology / Q000503:physiopathology*; D011655:Pulmonary Embolism / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D013927:Thrombosis / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D066253:Vascular Remodeling; D014655:Vascular Resistance / Q000502:physiology*