Annals of Biomedical Engineering

, Volume 38, Issue 3, pp 788–800 | Cite as

Quantification of Hemodynamic Wall Shear Stress in Patients with Bicuspid Aortic Valve Using Phase-Contrast MRI



Bicuspid aortic valve (BAV) is often concomitant with aortic dilatation, aneurysm, and dissection. This valve lesion and its complications may affect positional and temporal wall shear stress (WSS), a parameter reported to regulate transcriptional events in vascular remodeling. Thus, this pilot study seeks to determine if the WSS in the ascending aorta (AAo) of BAV patients differs from control patients. Phase-contrast magnetic resonance imaging (PC-MRI) was used to perform flow analysis at the level of the AAo in 15 BAV and 15 control patients. Measurement of the aorta dimensions, flow rates, regurgitant fraction (RF), flow reversal ratio (FRR), temporal and spatial WSS, and shear range indices (SRI) were performed. The BAV and control group showed a significant difference between the circumferentially averaged WSS (p = 0.03) and positional WSS at systole (minimum p < 0.001). Regressions found that SRI (r = 0.77, p < 0.001), RF (r = 0.68, p < 0.001), and WSS at systole (r = 0.66, p < 0.001) were correlated to AAo size. The spatial distribution and magnitude of systolic WSS in BAV patients (−6.7 ± 4.3 dynes/cm2) differed significantly from control patients (−11.5 ± 6.6 dynes/cm2, p = 0.03). The SRI metric, a measure of shear symmetry along the lumen circumference, was also significantly different (p = 0.006) and indicated a heterogenic pattern of dilatation in the BAV patients.


BAV WSS Aorta Artery Valve lesion Viscous forces Blood flow Dissection Dilation Aneurysm 



Funded in part by NIH T32 HL72738, K24 HL081506, P50 HL084923, F31 EB006695 and a research grant from Siemens Medical. The authors thank the radiology and cardiology staff at The Children’s Hospital, Denver, specifically Dr. Vernon Chapman, Katherine Bushur, and Barret Daniels for assistance with this study.


  1. 1.
    Bauer, M., H. Siniawski, M. Pasic, B. Schaumann, and R. Hetzer. Different hemodynamic stress of the ascending aorta wall in patients with bicuspid and tricuspid aortic valve. J. Card. Surg. 21:218–220, 2006.CrossRefPubMedGoogle Scholar
  2. 2.
    Beroukhim, R. S., T. L. Kruzick, A. L. Taylor, D. X. Gao, and A. T. Yetman. Progression of aortic dilation in children with a functionally normal bicuspid aortic valve. Am. J. Cardiol. 98:828–830, 2006.CrossRefPubMedGoogle Scholar
  3. 3.
    Buchanan, J. R., C. Kleinstreuer, G. A. Truskey, and M. Lei. Relation between non-uniform hemodynamics and sites of altered permeability and lesion growth at the rabbit aorto-celiac junction. Atherosclerosis 143:27–40, 1999.CrossRefPubMedGoogle Scholar
  4. 4.
    Cecconi, M., M. Manfrin, A. Moraca, R. Zanoli, P. L. Colonna, M. G. Bettuzzi, S. Moretti, D. Gabrielli, and G. P. Perna. Aortic dimensions in patients with bicuspid aortic valve without significant valve dysfunction. Am. J. Cardiol. 95:292–294, 2005.CrossRefPubMedGoogle Scholar
  5. 5.
    Cecconi, M., S. Nistri, A. Quarti, M. Manfrin, P. L. Colonna, E. Molini, and G. P. Perna. Aortic dilatation in patients with bicuspid aortic valve. J. Cardiovasc. Med. 7:11–20, 2006.Google Scholar
  6. 6.
    Cheng, C. P., D. Parker, and C. A. Taylor. Quantification of wall shear stress in large blood vessels using lagrangian interpolation functions with cine phase-contrast magnetic resonance imaging. Ann. Biomed. Eng. 30:1020–1032, 2002.CrossRefPubMedGoogle Scholar
  7. 7.
    Cheng, C., D. Tempel, R. van Haperen, A. van der Baan, F. Grosveld, M. J. A. P. Daemen, R. Krams, and R. de Crom. Atherosclerotic lesion size and vulnerability are determined by patterns of fluid shear stress. Circulation 113:2744–2753, 2006.CrossRefPubMedGoogle Scholar
  8. 8.
    Cripe, L., G. Andelfinger, L. J. Martin, K. Shooner, and D. W. Benson. Bicuspid aortic valve is heritable. J. Am. Coll. Cardiol. 44:138–143, 2004.CrossRefPubMedGoogle Scholar
  9. 9.
    Della Corte, A., C. Bancone, C. Quarto, G. Dialetto, F. E. Covino, M. Scardone, G. Caianiello, and M. Cotrufo. Predictors of ascending aortic dilatation with bicuspid aortic valve: a wide spectrum of disease expression. Eur. J. Cardiothorac. Surg. 31:397–404, 2007.CrossRefPubMedGoogle Scholar
  10. 10.
    Fedak, P. W. M., S. Verma, T. E. David, R. L. Leask, R. D. Weisel, and J. Butany. Clinical and pathophysiological implications of a bicuspid aortic valve. Circulation 106:900–904, 2002.CrossRefPubMedGoogle Scholar
  11. 11.
    Firmin, D. N., G. L. Nayler, P. J. Kilner, and D. B. Longmore. The application of phase-shifts in NMR for flow measurement. Magnet. Reson. Med. 14:230–241, 1990.CrossRefGoogle Scholar
  12. 12.
    Frayne, R., D. A. Steinman, C. R. Ethier, and B. K. Rutt. Accuracy of MR phase-contrast velocity-measurements for unsteady-flow. J. Magn. Reson. Im. 5:428–431, 1995.CrossRefGoogle Scholar
  13. 13.
    Frydrychowicz, A., A. Berger, A. F. Stalder, M. F. Russe, A. Harloff, M. Langer, J. Hennig, and M. Markl. Diameter-dependence of aortic hemodynamics: does size matter? In: ISMRM 16th Annual Scientific Meeting, May 3–9, Toronto, ON, 2008. Abstract 2828.Google Scholar
  14. 14.
    Frydrychowicz, A., A. Harloff, B. Jung, M. Zaitsev, E. Weigang, T. A. Bley, M. Langer, J. Hennig, and M. Markl. Time-resolved, 3-dimensional magnetic resonance flow analysis at 3T: visualization of normal and pathological aortic vascular hemodynamics. J. Comput. Assist. Tomo. 31:9–15, 2007.CrossRefGoogle Scholar
  15. 15.
    Grotenhuis, H. B., J. Ottenkamp, J. J. M. Westenberg, J. J. Bax, L. J. M. Kroft, and A. de Roos. Reduced aortic elasticity and dilatation are associated with aortic regurgitation and left ventricular hypertrophy in nonstenotic bicuspid aortic valve patients. J. Am. Coll. Cardiol. 49:1660–1665, 2007.CrossRefPubMedGoogle Scholar
  16. 16.
    Haycock, G. M., G. J. Schwartz, and D. H. Wisotsky. Geometric method for measuring body surface area: a height weight formula validated in infants, children and adults. J. Pediatr. 93:62–66, 1978.CrossRefPubMedGoogle Scholar
  17. 17.
    Holmes, K. W., C. U. Lehmann, D. Dalal, K. Nasir, H. C. Dietz, W. J. Ravekes, W. R. Thompson, and P. J. Spevak. Progressive dilation of the ascending aorta in children with isolated bicuspid aortic valve. Am. J. Cardiol. 99:978–983, 2007.CrossRefPubMedGoogle Scholar
  18. 18.
    Hope, M. D., A. K. Meadows, T. A. Hope, K. G. Ordovas, G. P. Reddy, M. T. Alley, and C. B. Higgins. Evaluation of bicuspid aortic valve and aortic coarctation with 4D flow magnetic resonance imaging. Circulation 117:2818–2819, 2008.CrossRefPubMedGoogle Scholar
  19. 19.
    Jin, S., J. Oshinski, and D. P. Giddens. Effects of wall motion and compliance on flow patterns in the ascending aorta. J. Biomech. Eng. 125:347–354, 2003.CrossRefPubMedGoogle Scholar
  20. 20.
    Keane, M. G., S. E. Wiegers, T. Plappert, A. Pochettino, J. E. Bavaria, and M. G. S. J. Sutton. Bicuspid aortic valves are associated with aortic dilatation out of proportion to coexistent valvular lesions. Circulation 102:35–39, 2000.Google Scholar
  21. 21.
    Kozerke, S., M. B. Scheidegger, E. M. Pedersen, and P. Boesiger. Heart motion adapted cine phase-contrast flow measurements through the aortic valve. Magn. Reson. Med. 42:970–978, 1999.CrossRefPubMedGoogle Scholar
  22. 22.
    Ku, D. N., C. L. Biancheri, R. I. Pettigrew, J. W. Peifer, C. P. Markou, and H. Engels. Evaluation of magnetic-resonance velocimetry for steady flow. J. Biomech. Eng. 112:464–472, 1990.CrossRefPubMedGoogle Scholar
  23. 23.
    La Canna, G., E. Ficarra, E. Tsagalau, M. Nardi, A. Morandini, A. Chieffo, F. Maisano, and O. Alfieri. Progression rate of ascending aortic dilation in patients with normally functioning bicuspid and tricuspid aortic valves. Am. J. Cardiol. 98:249–253, 2006.CrossRefPubMedGoogle Scholar
  24. 24.
    Lewin, M. B., and C. M. Otto. The bicuspid aortic valve: adverse outcomes from infancy to old age. Circulation 111:832–834, 2005.CrossRefPubMedGoogle Scholar
  25. 25.
    Nichols, W., and M. F. O’Rourke. McDonald’s Blood Flow in Arteries: Theoretical, Experimental and Clinical Principles. London: Hodder Arnold, p. 19, 2005.Google Scholar
  26. 26.
    Papaharilaou, Y., D. J. Doorly, and S. J. Sherwin. Assessing the accuracy of two-dimensional phase-contrast MRI measurements of complex unsteady flows. J. Magn. Reson. Imaging 14:714–723, 2001.CrossRefPubMedGoogle Scholar
  27. 27.
    Robicsek, F., M. J. Thubrikar, J. W. Cook, and B. Fowler. The congenitally bicuspid aortic valve: how does it function? Why does it fail? Ann. Thorac. Surg. 77:177–184, 2004.CrossRefPubMedGoogle Scholar
  28. 28.
    Silber, H. A., D. A. Bluemke, P. Ouyang, Y. P. P. Du, W. S. Post, and J. A. C. Lima. The relationship between vascular wall shear stress and flow-mediated dilation: endothelial function assessed by phase-contrast magnetic resonance angiography. J. Am. Coll. Cardiol. 38:1859–1865, 2001.CrossRefPubMedGoogle Scholar
  29. 29.
    Sluysmans, T., and S. D. Colan. Theoretical and empirical derivation of cardiovascular allometric relationships in children. J. Appl. Physiol. 99:445–457, 2005.CrossRefPubMedGoogle Scholar
  30. 30.
    Warren, A. E., M. L. Boyd, C. O’Connell, and L. Dodds. Dilatation of the ascending aorta in paediatric patients with bicuspid aortic valve: frequency, rate of progression and risk factors. Heart 92:1496–1500, 2006.CrossRefPubMedGoogle Scholar
  31. 31.
    Wilton, E., and M. Jahangiri. Post-stenotic aortic dilatation. J. Cardiothorac. Surg. 1:7–18, 2006.CrossRefPubMedGoogle Scholar
  32. 32.
    Womersley, J. R. Method for the calculation of velocity, rate of flow and viscous drag in arteries when the pressure gradient is known. J. Physiol. 127:553–563, 1955.PubMedGoogle Scholar
  33. 33.
    Yasuda, H., S. Nakatani, M. Stugaard, Y. Tsujita-Kuroda, K. Bando, J. Kobayashi, M. Yamagishi, M. Kitakaze, S. Kitamura, and K. Miyatake. Failure to prevent progressive dilation of ascending aorta by aortic valve replacement in patients with bicuspid aortic valve: comparison with tricuspid aortic valve. Circulation 108:291–294, 2003.CrossRefGoogle Scholar

Copyright information

© Biomedical Engineering Society 2009

Authors and Affiliations

  • Alex J. Barker
    • 1
  • Craig Lanning
    • 2
    • 3
  • Robin Shandas
    • 1
    • 2
    • 3
  1. 1.Department of Mechanical EngineeringUniversity of ColoradoBoulderUSA
  2. 2.Division of Pediatric CardiologyThe Children’s HospitalDenverUSA
  3. 3.Center for BioengineeringUniversity of Colorado Denver Medical CampusAuroraUSA

Personalised recommendations