A computational study on the influence of catheter-delivered intravascular probes on blood flow in a coronary artery model  Ryo Torii, Nigel B. Wood, Alun D. Hughes, Simon A. Thom, Jazmin Aguado-Sierra, Justin E. Davies, Darrel P. Francis, Kim H. Parker, X. Yun. Xu  Journal of Biomechanics  Volume 40, Issue 11, Pages 2501-2509 (January 2007) DOI: 10.1016/j.jbiomech.2006.11.004 Copyright © 2006 Terms and Conditions

Fig. 1 Schematic illustration of the catheter-probe model in an idealised coronary artery. The diameters of catheter model d are 0.3, 0.6 and 1.0 mm. Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 2 Velocity waveforms measured with a commercial ultrasound Doppler probe FloWire (VolcanoTM Corporation) with 1kHz sampling rate at the proximal site of RCA (a) and idealised waveform used in the model (b). umax is the maximum velocity at the beginning of the curved section without a catheter, and uin is the mean velocity at the inlet. Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 3 Variation of velocity profiles at the beginning of the curved section without (a) and with a 0.3mm diameter probe (b). The horizontal axis denotes the position in the radial axis normalised with the radius of the pipe r0(=1.5mm). Negative radial position denotes the location at inside of the vessel curvature. The flow rate is kept the same for both cases. Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 4 The computational mesh for d=0.3mm case near the top of the curved section (a), magnified around the probe tip (b) and cross section (c). Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 5 Comparison of the time-varying pressure drop (p1-p2) for all cases. (a) Monitoring points and (b) pressure profile. Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 6 The pressure waveform measured with a commercial pressure probe WaveWire (VolcanoTM Corporation) with 1kHz sampling rate at the proximal site of RCA. Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 7 Comparison of axial velocity variations at the location of ultrasound sample volume for all cases. Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 8 Comparison of axial velocity profiles at the probe tip (left) and 5mm downstream of the tip (right) for all cases. The horizontal axis denotes the position in the radial axis normalised with the radius of the pipe r0(=1.5mm). Negative radial position denotes the location at inside of the vessel curvature ((a) at the middle of the accelerating phase, (b) at peak flow and (c) at the middle of the decelerating phase). Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 9 Secondary flow in the same plane as the probe tip (S in (a)) at peak flow without (b) and with a 0.3-mm diameter probe (c). Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 10 Dimensions of ultrasound Doppler sampling volume (a) and re-development of the axial flow velocity along L at peak flow (b). Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 11 Comparison of the axial velocity profiles at the probe tip (left) and 5mm downstream of the tip (right) for different inflow velocity. The horizontal axis denotes the position in the radial axis normalised with the radius of the pipe r0(=1.5mm). Negative radial position denotes the location at inside of the vessel curvature ((a) at the middle of the accelerating phase, (b) at peak flow and (c) at the middle of the decelerating phase). Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions

Fig. 12 Comparison of the time-varying pressure drop (a) and velocity (b) profiles for the cases with a realistic velocity waveform. Journal of Biomechanics 2007 40, 2501-2509DOI: (10.1016/j.jbiomech.2006.11.004) Copyright © 2006 Terms and Conditions