title: Severe Pulmonary Arteriopathy Is Associated with Persistent Hypoxemia after Pulmonary Endarterectomy in Chronic Thromboembolic Pulmonary Hypertension.
abstract: BACKGROUND
  Chronic thromboembolic pulmonary hypertension (CTEPH) is characterized by occlusion of pulmonary arteries by organized chronic thrombi. Persistent hypoxemia and residual pulmonary hypertension (PH) following successful pulmonary endarterectomy (PEA) are clinically important problems; however, the underlying mechanisms remain unclear. We have previously reported that residual PH is closely related to severe pulmonary vascular remodeling and hypothesize that this arteriopathy might also be involved in impaired gas exchange. The purpose of this study was to evaluate the association between hypoxemia and pulmonary arteriopathy after PEA.
  
  
  RESULTS
  Between December 2011 and November 2014, 23 CTEPH patients underwent PEA and lung biopsy. The extent of pulmonary arteriopathy was quantified pathologically in lung biopsy specimens. We then analyzed the relationship between the severity of pulmonary arteriopathy and gas exchange after PEA. We observed that the severity of pulmonary arteriopathy was negatively correlated with postoperative and follow-up PaO2 (postoperative PaO2: r = -0.73, p = 0.0004; follow-up PaO2: r = -0.66, p = 0.001), but not with preoperative PaO2 (r = -0.373, p = 0.08). Multivariate analysis revealed that the obstruction ratio and patient age were determinants of PaO2 one month after PEA (R2 = 0.651, p = 0.00009). Furthermore, the obstruction ratio and improvement of pulmonary vascular resistance were determinants of PaO2 at follow-up (R2 = 0.545, p = 0.0002). Severe pulmonary arteriopathy might increase the alveolar-arterial oxygen difference and impair diffusion capacity, resulting in hypoxemia following PEA.
  
  
  CONCLUSIONS
  The severity of pulmonary arteriopathy was closely associated with postoperative and follow-up hypoxemia.
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.|Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Takayuki
authors: http://orcid.org/0000-0001-5725-1810
authors: T
authors: Jujo
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.|Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Nobuhiro
authors: N
authors: Tanabe
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Seiichiro
authors: S
authors: Sakao
authors: Department of Pathology, National Cerebral and Cardiovascular Center, 5-7-1, Fujishiro-Dai, Suita City, Osaka, 565-8565, Japan.
authors: Hatsue
authors: H
authors: Ishibashi-Ueda
authors: Department of Cardiovascular Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Keiichi
authors: K
authors: Ishida
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Akira
authors: A
authors: Naito
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Fumiaki
authors: F
authors: Kato
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Takao
authors: T
authors: Takeuchi
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.|Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Ayumi
authors: A
authors: Sekine
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.|Department of Advanced Medicine in Pulmonary Hypertension, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Rintaro
authors: R
authors: Nishimura
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Toshihiko
authors: T
authors: Sugiura
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Ayako
authors: A
authors: Shigeta
authors: Department of Cardiovascular Surgery, Chiba Medical Center, National Hospital Organization, 4-1-2, Tsubakimori, Chuo-ku, Chiba City, 260-8606, Japan.
authors: Masahisa
authors: M
authors: Masuda
authors: Department of Respirology (B2), Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-Ku, Chiba City, 260-8670, Japan.
authors: Koichiro
authors: K
authors: Tatsumi
mesh_terms: D000368:Aged; D006328:Cardiac Catheterization; D004691:Endarterectomy; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000097:blood* / Q000473:pathology*; D000860:Hypoxia / Q000097:blood / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D011184:Postoperative Period; D011651:Pulmonary Artery / Q000473:pathology; D011655:Pulmonary Embolism / Q000097:blood* / Q000473:pathology / Q000601:surgery; D014655:Vascular Resistance / Q000502:physiology
chemical_list: D010100:Oxygen