title: A patient-specific virtual stenotic model of the coronary artery to analyze the relationship between fractional flow reserve and wall shear stress.
abstract: OBJECTIVE
  As the stenotic severity of a patient increases, fractional flow reserve (FFR) decreases, whereas the maximum wall shear stress (WSSmax) increases. However, the way in which these values can change according to stenotic severity has not previously been investigated. The aim of this study is to devise a virtual stenosis model to investigate variations in the coronary hemodynamic parameters of patients according to stenotic severity.
  
  
  METHODS
  To simulate coronary hemodynamics, a three-dimensional (3D) coronary artery model of computational fluid dynamics is coupled with a lumped parameter model of the coronary micro-vasculature and venous system.
  
  
  RESULTS
  To validate the present method, we first simulated 13 patient-specific models of the coronary arteries and compared the results with those obtained clinically. Then, virtually narrowed coronary arterial models derived from the patient-specific cases were simulated to obtain the WSSmax and FFR values. The variations in FFR and WSSmax against the percentage of diameter stenosis in clinical cases were reproducible by the virtual stenosis models. We also found that the simulated FFR values were linearly correlated with the WSSmax values, but the linear slope varied by patient.
  
  
  CONCLUSIONS
  We implemented 130 additional virtual models of stenosed coronary arteries based on data from 13 patients and obtained statistically meaningful results that were identical to the large-scale clinical studies. And the slope of the correlation line between FFR and WSSmax may help clinicians to design treatment plans for patients.
authors: Department of Mechanical and Biomedical Engineering, Kangwon National University, Chuncheon, Republic of Korea.
authors: Kyung Eun
authors: KE
authors: Lee
authors: Department of Mechanical and Biomedical Engineering, Kangwon National University, Chuncheon, Republic of Korea.
authors: Gook Tae
authors: GT
authors: Kim
authors: Department of Thoracic & Cardiovascular Surgery, Seoul National University Hospital, Seoul, Republic of Korea.
authors: Jeong Sang
authors: JS
authors: Lee
authors: Department of Cardiology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea.
authors: Ju-Hyun
authors: JH
authors: Chung
authors: Department of Cardiology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea.
authors: Eun-Seok
authors: ES
authors: Shin
authors: Department of Mechanical and Biomedical Engineering, Kangwon National University, Chuncheon, Republic of Korea. Electronic address: ebshim@kangwon.ac.kr.
authors: Eun Bo
authors: EB
authors: Shim
mesh_terms: D000368:Aged; D003198:Computer Simulation; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index
keywords: Coronary artery hemodynamics; Fractional flow reserve; Physiological simulation; Virtual stenosis model; Wall shear stress