The effect of myocardial anisotropy on volume measurement using conductance catheter techniques in the right ventricle

The effect of myocardial anisotropy on ventricular volume measurements, taken using conductance catheter techniques in the right ventricle, is investigated using finite element models of the isolated heart. The governing equation is Poisson's equation. Model results show calculated volumes are more accurate if anisotropy is included in the model, due to increased confinement of current within the ventricle. This can lead to more accurate blood volume measurements in the right ventricle. References J. Baan, T. T. Aouw Jong, P. L. M. Kerkhof, R. J. Moene, A. D. Van Dijk, E. T. Van Der Velde, and J. Koops. Continuous stroke volume and cardiac output from intra-ventricular dimensions obtained with impedance catheter. Cardiovascular Research, 15:328--334, 1981. L. A. Geddes and L. E. Baker. The specific resistance of biological meterial: a compendium of data for the biomedical engineer and physiologist. Med. Biol. Eng., 5:271--293, 1967. B. Gopakumaran, J. H. Petre, S. Krucinski, and P. Murray. Real-time continuous measurement of right ventricular volume using a conductance catheter. Biom. Instrum. and Techno., 30(5):427--438, 1996. C. Johnson. Numerical solution of partial differential equations by the finite element method. Cambridge University Press, 1990. P. M. Nielsen, I. J. Le Grice, B. H. Smaill, and P. J. Hunter. Mathematical model of geometry and fibrous structure of the heart. American Journal of Heart and Circulatory Physiology, 260:H1365--H1378, 1991. P. P. Silvester and R. L. Ferrari. Finite elements for electrical engineer. Cambridge University Press, 1996. J. G. Stinstra, B. Hopenfeld, and R. S. Macleod. On the passive cardiac conductivity. Ann. Biomed. Eng., 33:1743--1751, 2005. C. Thaijiam and T. J. Gale. Analytical and numerical studies of volume measurement using conductance catheter techniques. In Proceedings of the 2005 IEEE Engineering in Medicine and Biology Society 27th Annual Conference, pages 2291--2294, 2005. C. Thaijiam and T. J. Gale. The effect studies of fiber orientation with volume measurement by using conductance catheter techniques. In Proceedings of the 2006 IEEE Engineering in Medicine and Biology Society 28th Annual Conference, pages 5981--5984, 2006. C. Thaijiam and T. J. Gale. Studies of single and dual excitation using conductance catheter techniques. In The Fourth IASTED International Conference on Biomedical Engineering, pages 294--299, 2006. P. A. White and A. N. Redington. Right ventricular volume measurement: can conductance do it better? Physio. Meas., 21:R23--R41, 2000. J. C. Woodard, C. D. Bertram, and B. S. Gow. Dectecting right ventricular volume changes using the conductance catheter. PACE, 15, 1992