title: Hemodynamic analysis of coronary circulation in angulated coronary stenosis following stenting.
abstract: The present study in angulated coronary stenosis used human in vivo hemodynamic parameters and computed simulation, both qualitatively and qualitatively, to evaluate the influence of flow velocity and wall shear stress (WSS) on coronary atherosclerosis, the changes of hemodynamic indices following coronary stenting, and their effect on evolving in-stent restenosis. Initial and follow-up coronary angiographies in patients with angulated coronary stenosis were performed (n=60). The optimal degree of coronary stenting for angulated coronary stenosis had two models, the less than 50% angle changed group (model 1, n=33) and the more than 50% angle changed group (model 2, n=27). This angle change was based on the percentage change of vascular angle between pre- and post-intracoronary stenting. The flow-velocity wave obtained from in vivo intracoronary Doppler study data was used for in vitro numerical simulation. Spatial and temporal patterns of the flow-velocity vector and recirculation area were drawn throughout the selected segment of coronary models. WSS of pre- and post-intracoronary stenting was calculated from three-dimensional computer simulation. As results, follow-up coronary angiogram demonstrated significant difference in the percentage of diameter stenosis between the two groups (group 1: 40.3 +/- 30.2 vs. group 2: 25.5 +/- 22.5%, p < 0.05). Negative shear area on 3D simulation, which is consistent with the re-circulation area of flow vector, was noted on the inner wall of the post-stenotic area before stenting. The negative WSS disappeared after stenting. High spatial and temporal WSS before stenting fell within the range of physiologic WSS after stenting. This finding was more prominent in model 2 (p < 0.01). The present study suggests that hemodynamic forces exerted by pulsatile coronary circulation, termed WSS, might affect the evolution of atherosclerosis within the angulated vascular curvature. Moreover, geometric characteristics, such as the angular difference between pre- and post- intracoronary stenting might define optimal rheologic properties for vascular repair after stenting.
authors.affiliation: Department of Internal Medicine, College of Medicine, Inje University, Sanggye Paik Hospital, Seoul, Korea.
authors.forename: Byoung Kwon
authors.initials: BK
authors.lastname: Lee
authors.forename: Ju Yong
authors.initials: JY
authors.lastname: Lee
authors.forename: Bum Kee
authors.initials: BK
authors.lastname: Hong
authors.forename: Byoung Eun
authors.initials: BE
authors.lastname: Park
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Kim
authors.forename: Dong Yeon
authors.initials: DY
authors.lastname: Kim
authors.forename: Yun Hyeong
authors.initials: YH
authors.lastname: Cho
authors.forename: Se Jung
authors.initials: SJ
authors.lastname: Yoon
authors.forename: Young Won
authors.initials: YW
authors.lastname: Yoon
authors.forename: Hyuck Moon
authors.initials: HM
authors.lastname: Kwon
authors.forename: Hyung Woon
authors.initials: HW
authors.lastname: Roh
authors.forename: Il
authors.initials: I
authors.lastname: Kim
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Park
authors.forename: Seong Min
authors.initials: SM
authors.lastname: Han
authors.forename: Min Tae
authors.initials: MT
authors.lastname: Cho
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Suh
authors.forename: Hyun Seung
authors.initials: HS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000503:physiopathology* / Q000628:therapy; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D015607:Stents; D013314:Stress, Mechanical