title: In vitro assessment of physiological impact of recipient artery intervention on the contralateral donor artery.
abstract: BACKGROUND
  Donor artery fractional flow reserve (FFR) often improves after treatment of recipient artery stenosis, but the physiological mechanism underlying this phenomenon has not been elucidated. This study aimed to assess two novel equations that explain the donor-recipient artery interaction.
  
  
  METHODS
  Eq. (A) predicts the donor artery FFR after complete release of recipient artery stenosis, while Eq. (B) predicts the donor artery FFR after partial release of recipient artery stenosis. Eq. (B) is a general form of Eq. (A). FFR'1−pred = ((FFR1−CFI1)(FFR2−CFI2)−CFI1CFI2(1−FFR1)(1−FFR2)+CFI1(1−FFR1)(1−CFI2))/((1−C FI1)(FFR2−CFI2)) (A) FFR''1−pred = ((FFR1−CFI1)(FFR2−CFI2)−CFI1CFI2(1−FFR1)(1−FFR2)+CFI1(1−FFR1)(1−CFI2))FFR'2/((1−C FI1)(FFR2−CFI2)) (B) Eqs. (A) and (B) were assessed using an in vitro model of coronary circulation with a collateral channel connecting the donor and recipient arteries.
  
  
  RESULTS
  The donor artery FFR always improved after releasing the recipient artery stenosis. A good linear correlation was found between the predicted FFR of Eq. (A) and the actual FFR (n=40, r=0.95, p<0.0001) and between the predicted FFR of Eq. (B) and the actual FFR (n=40, r=0.94, p<0.0001).
  
  
  CONCLUSIONS
  Eqs. (A) and (B) accurately predicted the true FFR value of the donor artery in a coronary circulation model and explain the donor-recipient artery interaction observed in clinical practice.
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Hiroki
authors: H
authors: Watanabe
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan. Electronic address: naritatu@kuhp.kyoto-u.ac.jp.
authors: Naritatsu
authors: N
authors: Saito
authors: Department of Cardiovascular Medicine, Gifu Heart Center, Gifu, Japan.
authors: Hitoshi
authors: H
authors: Matsuo
authors: Department of Cardiovascular Medicine, Gifu Heart Center, Gifu, Japan.
authors: Yoshiaki
authors: Y
authors: Kawase
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Shin
authors: S
authors: Watanabe
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Bingyuan
authors: B
authors: Bao
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Erika
authors: E
authors: Yamamoto
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Hirooki
authors: H
authors: Higami
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Kenji
authors: K
authors: Nakatsuma
authors: Department of Cardiovascular Medicine, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors: Takeshi
authors: T
authors: Kimura
mesh_terms: D003097:Collateral Circulation / Q000502:physiology*; D017023:Coronary Angiography / Q000379:methods; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000628:therapy*; D003331:Coronary Vessels / Q000502:physiology*; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D066298:In Vitro Techniques; D016014:Linear Models; D008955:Models, Cardiovascular
keywords: Chronic total occlusion; Collateral circulation; Coronary physiology; Fractional flow reserve