Counterpoint: Left ventricular volume during diastasis is not the physiological in vivo equilibrium volume and is not related to diastolic suction.

rat cardiac myocytes. Circ Res 79: 619–626, 1996. 14. Jobsis PD, Ashikaga H, Wen H, Rothstein EC, Horvath KA, McVeigh ER, Balaban RS. Visceral pericardium: macromolecular structure and contribution to passive mechanical properties of the left ventricle. Am J Physiol Heart Circ Physiol 293: H3379–H3387, 2007. 15. Katz LN. The role played by the ventricular relaxation process in filling the ventricle. Am J Physiol 95: 542–553, 1930. 16. Kovács SJ Jr, Barzilai B, Perez JE. Evaluation of diastolic function with Doppler echocardiography: the PDF formalism. Am J Physiol Heart Circ Physiol 252: H178–H187, 1987. 17. Kovács SJ, Meisner JS, Yellin EL. Modeling of diastole. Cardiol Clin 18: 459–487, 2000. 18. Little WC. Diastolic dysfunction beyond distensibility: adverse effects of ventricular dilatation. Circulation 112: 2888–2890, 2005. 19. Little WC, Oh JK. Echocardiographic evaluation of diastolic function can be used to guide clinical care. Circulation 120: 802–809, 2009. 20. Nagueh SF, Appleton CP, Gillebert TC, Marino PN, Oh JK, Smiseth OA, Waggoner AD, Flachskampf FA, Pellikka PA, Evangelisa A. Recommendations for the evaluation of left ventricular diastolic function by echocardiography. J Am Soc Echo 22: 107–133, 2009. 21. Nikolic S, Yellin EL, Tamura K, Vetter H, Tamura T, Meisner JS, Frater RW. Passive properties of canine left ventricle: diastolic stiffness and restoring forces. Circ Res 62: 1210–1222, 1988. 22. Omens JH, Fung YC. Residual strain in rat left ventricle. Circ Res 66: 37–45, 1990. 23. Robinson TF, Factor SM, Sonnenblick EH. The heart as a suction pump. Sci Am 254: 84–91, 1986. 24. Rothfeld JM, LeWinter MM, Tischler MD. Left ventricular systolic torsion and early diastolic filling by echocardiography in normal humans. Am J Cardiol 81: 1465–1469, 1998. 25. Shmuylovich LS, Kovács SJ. Load-independent index of diastolic filling: model-based derivation with in vivo validation in control and diastolic dysfunction subjects. J Appl Physiol 101: 92–101, 2006. 26. Siegel RE. Galen’s System of Physiology and Medicine. Basel, Switzerland: Karger, 1968. 27. Yellin EL, Meisner J. Physiology of diastolic function and transmitral pressure-flow relations. Cardiol Clinics 18: 411–433, 2000. 28. Yotti R, Bermejo J, Antoranz JC, Rojo-Álvarez JL, Allue C, Silva J, Desco MM, Moreno M, Garcia-Fernandez MA. A noninvasive method for assessing impaired diastolic suction in patients with dilated cardiomyopathy. Circulation 112: 2921–2929, 2005. 29. Zhang W, Chung CS, Shmuylovich L, Kovács SJ. Is left ventricular volume during diastasis the real equilibrium volume and, what is its relationship to diastolic suction? J Appl Physiol 105: 1012–1014, 2007. 30. Zhang W, Kovács SJ. The diastatic pressure-volume relationship is not the same as the end-diastolic pressure-volume relationship. Am J Physiol Heart Circ Physiol 294: H2750–H2760, 2008.