BACKGROUND AND OBJECTIVES: Lesions of vascular bifurcation and their treatment outcomes have been evaluated by anatomical and physiological methods, such as intravascular ultrasound and fractional flow reserve (FFR). However, local changes in flow dynamics in lesions of bifurcation have not been well evaluated. This study aimed at evaluating changes in the local flow patterns of bifurcation lesions. MATERIALS AND METHODS: Eight (n=8) representative simulation-models were constructed: 1 normal bifurcation, 5 main-branch (MB) stenting models with various side-branch (SB) stenoses (ostial or non-ostial 75% diameter stenosis with 1- or 2-cm lesion lengths, ostial 75% diameter stenosis caused by carina shift), and 2 post-kissing models (no or 50% SB residual stenosis). Pressure, velocity, and wall shear stress (WSS) profiles around the bifurcation sites were investigated using computational fluid dynamics. RESULTS: Post-stenting models revealed significant pressure drop in the SB (FFR<0.75), excluding the carina shift model (FFR=0.89). In the post-kissing models, there was no significant pressure drop. All post-stenting models revealed eccentric low velocity flow patterns and areas of low WSS, primarily in the lateral wall on distal MB. Post-kissing angioplasty improved pressure drop in the SB but resulted in alteration of flow distribution in the MB. In the carina shift model, kissing ballooning resulted in deteriorated local flow conditions due to increased area of low velocity and WSS. CONCLUSION: This study suggests that the most commonly used bifurcation intervention strategy may cause local flow disturbances, which may partially explain high restenosis and event rates in patients with bifurcation lesions.
BACKGROUND AND OBJECTIVES: Lesions of vascular bifurcation and their treatment outcomes have been evaluated by anatomical and physiological methods, such as intravascular ultrasound and fractional flow reserve (FFR). However, local changes in flow dynamics in lesions of bifurcation have not been well evaluated. This study aimed at evaluating changes in the local flow patterns of bifurcation lesions. MATERIALS AND METHODS: Eight (n=8) representative simulation-models were constructed: 1 normal bifurcation, 5 main-branch (MB) stenting models with various side-branch (SB) stenoses (ostial or non-ostial 75% diameter stenosis with 1- or 2-cm lesion lengths, ostial 75% diameter stenosis caused by carina shift), and 2 post-kissing models (no or 50% SB residual stenosis). Pressure, velocity, and wall shear stress (WSS) profiles around the bifurcation sites were investigated using computational fluid dynamics. RESULTS: Post-stenting models revealed significant pressure drop in the SB (FFR<0.75), excluding the carina shift model (FFR=0.89). In the post-kissing models, there was no significant pressure drop. All post-stenting models revealed eccentric low velocity flow patterns and areas of low WSS, primarily in the lateral wall on distal MB. Post-kissing angioplasty improved pressure drop in the SB but resulted in alteration of flow distribution in the MB. In the carina shift model, kissing ballooning resulted in deteriorated local flow conditions due to increased area of low velocity and WSS. CONCLUSION: This study suggests that the most commonly used bifurcation intervention strategy may cause local flow disturbances, which may partially explain high restenosis and event rates in patients with bifurcation lesions.
Authors: Terje K Steigen; Michael Maeng; Rune Wiseth; Andrejs Erglis; Indulis Kumsars; Inga Narbute; Pål Gunnes; Jan Mannsverk; Oliver Meyerdierks; Svein Rotevatn; Matti Niemelä; Kari Kervinen; Jan S Jensen; Anders Galløe; Kjell Nikus; Saila Vikman; Jan Ravkilde; Stefan James; Jens Aarøe; Antti Ylitalo; Steffen Helqvist; Iwar Sjögren; Per Thayssen; Kari Virtanen; Mikko Puhakka; Juhani Airaksinen; Jens F Lassen; Leif Thuesen Journal: Circulation Date: 2006-10-23 Impact factor: 29.690
Authors: Thierry Lefèvre; John Ormiston; Giulio Guagliumi; Heinz-Peter Schultheiss; Laurent Quilliet; Bernhard Reimers; Philippe Brunel; Williams Wijns; H J Buettner; F Hartmann; Susan Veldhof; Karin Miquel; Xiaolu Su; Willem J van der Giessen Journal: J Am Coll Cardiol Date: 2005-08-16 Impact factor: 24.094
Authors: Yiannis S Chatzizisis; Ahmet Umit Coskun; Michael Jonas; Elazer R Edelman; Charles L Feldman; Peter H Stone Journal: J Am Coll Cardiol Date: 2007-06-08 Impact factor: 24.094
Authors: N H Pijls; B De Bruyne; K Peels; P H Van Der Voort; H J Bonnier; J J Bartunek J Koolen; J J Koolen Journal: N Engl J Med Date: 1996-06-27 Impact factor: 91.245