Doppler color flow "proximal isovelocity surface area" method for estimating volume flow rate: effects of orifice shape and machine factors

Department of Medicine, University of California, Irvine.

Previously described Doppler color flow mapping methods for estimating the severity of valvular regurgitation have focused on the distal jet. In this study, a newer Doppler color flow technique, focusing on the flow proximal to an orifice, was used. This method identifies a proximal isovelocity surface area (PISA) by displaying an aliasing interface. Volume flow rate (cm3/s) can be calculated as PISA (cm2) x aliasing velocity (cm/s). For planar circular orifices, a hemi-elliptic model accurately approximated the shape of PISA. Clinically, however, orifice shapes may be noncircular. In vitro flow experiments (n = 226) using orifices of various shapes (ellipse, square, triangle, star, rectangle) were performed. Volume flow rate calculated using a hemi-elliptic model for PISA was accurate, with average percent differences from actual flow rate = +4.3% for a square, -4.2% for a triangle, -4.7% for a star, -4.5% for an ellipse and -2.8% for a rectangle. However, average percent differences for calculated volume flow rates using a hemispheric model for PISA shape ranged from -11.6% (square) to -34.8% (rectangle). In addition, to evaluate whether PISA is influenced by machine factors, in vitro studies (n = 83) were performed.(ABSTRACT TRUNCATED AT 250 WORDS)

This article has been cited by other articles:

				X. Zeng, R. A. Levine, L. Hua, E. L. Morris, Y. Kang, M. Flaherty, N. V. Morgan, and J. Hung Diagnostic Value of Vena Contracta Area in the Quantification of Mitral Regurgitation Severity by Color Doppler 3D Echocardiography Circ Cardiovasc Imaging, September 1, 2011; 4(5): 506 - 513. [Abstract] [Full Text] [PDF]

				S. Chandra, I. S. Salgo, L. Sugeng, L. Weinert, S. H. Settlemier, V. Mor-Avi, and R. M. Lang A three-dimensional insight into the complexity of flow convergence in mitral regurgitation: adjunctive benefit of anatomic regurgitant orifice area Am J Physiol Heart Circ Physiol, September 1, 2011; 301(3): H1015 - H1024. [Abstract] [Full Text] [PDF]

				N. A. Marsan, J. J.M. Westenberg, C. Ypenburg, V. Delgado, R. J. van Bommel, S. D. Roes, G. Nucifora, R. J. van der Geest, A. de Roos, J. C. Reiber, et al. Quantification of Functional Mitral Regurgitation by Real-Time 3D Echocardiography: Comparison With 3D Velocity-Encoded Cardiac Magnetic Resonance J. Am. Coll. Cardiol. Img., November 1, 2009; 2(11): 1245 - 1252. [Abstract] [Full Text] [PDF]

				T. Buck, B. Plicht, P. Kahlert, I. M. Schenk, P. Hunold, and R. Erbel Effect of Dynamic Flow Rate and Orifice Area on Mitral Regurgitant Stroke Volume Quantification Using the Proximal Isovelocity Surface Area Method J. Am. Coll. Cardiol., August 26, 2008; 52(9): 767 - 778. [Abstract] [Full Text] [PDF]

				A. S. Lambert Proximal Isovelocity Surface Area Should Be Routinely Measured in Evaluating Mitral Regurgitation: A Core Review Anesth. Analg., October 1, 2007; 105(4): 940 - 943. [Abstract] [Full Text] [PDF]

				R. A. Levine and E. Schwammenthal Ischemic Mitral Regurgitation on the Threshold of a Solution: From Paradoxes to Unifying Concepts Circulation, August 2, 2005; 112(5): 745 - 758. [Full Text] [PDF]

				T. Buck, B. Plicht, P. Hunold, R. A. Mucci, R. Erbel, and R. A. Levine Broad-beam spectral Doppler sonification of the vena contracta using matrix-array technology: A new solution for semi-automated quantification of mitral regurgitant flow volume and orifice area J. Am. Coll. Cardiol., March 1, 2005; 45(5): 770 - 779. [Abstract] [Full Text] [PDF]

				M. Ishii, K. Hashino, G. Eto, T. Tsutsumi, W. Himeno, Y. Sugahara, H. Muta, J. Furui, T. Akagi, Y. Ito, et al. Quantitative Assessment of Severity of Ventricular Septal Defect by Three-Dimensional Reconstruction of Color Doppler-Imaged Vena Contracta and Flow Convergence Region Circulation, February 6, 2001; 103(5): 664 - 669. [Abstract] [Full Text] [PDF]

				T. Buck, R. A. Mucci, J. L. Guerrero, G. Holmvang, M. D. Handschumacher, and R. A. Levine The Power-Velocity Integral at the Vena Contracta : A New Method for Direct Quantification of Regurgitant Volume Flow Circulation, August 29, 2000; 102(9): 1053 - 1061. [Abstract] [Full Text] [PDF]

				J. Hung, Y. Otsuji, M. D. Handschumacher, E. Schwammenthal, and R. A. Levine Mechanism of dynamic regurgitant orifice area variation in functional mitral regurgitation: Physiologic insights from the proximal flow convergence technique J. Am. Coll. Cardiol., February 1, 1999; 33(2): 538 - 545. [Abstract] [Full Text] [PDF]

				T. Shiota, M. Jones, A. Delabays, X. Li, I. Yamada, M. Ishii, P. Acar, S. Holcomb, N. G. Pandian, and D. J. Sahn Direct Measurement of Three-dimensionally Reconstructed Flow Convergence Surface Area and Regurgitant Flow in Aortic Regurgitation : In Vitro and Chronic Animal Model Studies Circulation, November 18, 1997; 96(10): 3687 - 3695. [Abstract] [Full Text]

				P. A. Grayburn and R. M. Peshock Noninvasive Quantification of Valvular Regurgitation: Getting to the Core of the Matter Circulation, July 15, 1996; 94(2): 119 - 121. [Full Text]

				T. Shiota, M. Jones, I. Yamada, R. S. Heinrich, M. Ishii, B. Sinclair, S. Holcomb, A. P. Yoganathan, and D. J. Sahn Effective Regurgitant Orifice Area by the Color Doppler Flow Convergence Method for Evaluating the Severity of Chronic Aortic Regurgitation : An Animal Study Circulation, February 1, 1996; 93(3): 594 - 602. [Abstract] [Full Text]