On Mitral Valve Dynamics and its Connection to Early Diastolic Flow
In the field of cardiology, the current ability to accurately detect diastolic dysfunction is unsatisfactory due to the lack of an effective diagnostic index. Isolated indexes obtained from echocardiography are all restricted to a certain aspect of ventricular diastolic function only, and individually cannot be regarded as a global representative for the left heart diastolic function. Due to complexity of cardiac motion, a reliable measure for diastolic performance should be a parameter that independently correlates with several aspects of cardiac function. The presence of trans-mitral vortex ring and its influence on dynamics of the mitral valve is a topic that has been recently received more attention in cardiovascular research. One obvious reason for this attention is to find better solutions to overcome our inability in interpretation of Doppler mitral inflow patterns for distinguishing a normal trans-mitral flow from a pseudonormal pattern. In the present study, we investigated the relationship among the ventricular early pressure drop, trans-mitral thrust as a force generated during diastolic filling and mitral annulus recoil through the index of vortex formation time. As a result, we found that vortex formation time is independently correlated to trans-mitral thrust, minimal ventricular pressure and pressure drop time-constant of isovolumic relaxation phase. Results also showed that trans-mitral thrust is maximized when the non-dimensional vortex formation time is in the range of 4 and 5.5 regardless of the shape of the waveform or the value of the pressure drop time-constant. In conclusion, this study confirms that vortex formation time, a non-dimensional measure for duration of E-wave, can be used as an index to assess diastolic ventricular function.
KeywordsVortex formation time Left ventricle Trans-mitral thrust Mitral annulus recoil
Authors would like to acknowledge Edwards Lifesciences Corporation for providing the bioprosthetic heart valves for this study.
- 1.Alam M., Höglund C. Assessment by echocardiogram of left ventricular diastolic function in healthy subjects using the atrioventricular plane displacement. Am. J. Cardiol. 1992; 69:505–565Google Scholar
- 5.Dincer I., Kumbasar D., Nergisoglu G., Atmaca Y., Kutlay S., Akyurek O., Sayin T., Erol C., Oral D. Assessment of left ventricular diastolic function with Doppler tissue imaging: effects of preload and place of measurements. Int. J. Cardiovasc. Imaging 2002; 18(3):155–160PubMedCrossRefGoogle Scholar
- 8.Fukuda K., Oki T., Tabata T., Luchi A., Ito S.. Regional left ventricular wall motion abnormalities in myocardial infarction and mitral annular descent velocities studied with pulsed tissue Doppler imaging. J. Am. Soc. Echocardiogr. 1998; 11(9):841–848. doi: 10.1016/S0894-7317(98)70003-3 PubMedCrossRefGoogle Scholar
- 15.Hung M. J., Cherng W. J., Kuo L. T., Wang C. H., Chern M. S.. Analysis of left atrial volume change rate during left ventricular diastolic phase with M-mode echocardiography for differentiation between normal and pseudonormal mitral inflow. Am. J. Cardiol. 2002; 89(5):552–556 doi: 10.1016/S0002-9149(01)02295-0 PubMedCrossRefGoogle Scholar
- 17.Kheradvar, A., R. Assadi, K. R. Jutzy, and R. Bansal. Transmitral vortex formation: a reliable indicator for pseudonormal diastolic dysfunction. J. Am. Coll. Cardiol. 51(10) supplement A: A104, 2008Google Scholar
- 25.Nagueh S. F., Middleton K. J., Kopelen H. A., Zoghbi W. A., Quinones M. A. Doppler tissue imaging: a noninvasive technique for evaluation of left ventricular relaxation and estimation of filling pressures. J. Am. Coll. Cardiol. 1997; 30:1527–1533. doi: 10.1016/S0735-1097(97)00344-6 PubMedCrossRefGoogle Scholar
- 27.Ommen S. R., Nishimura R. A., Appleton C. P., Miller F. A., Oh J. K., Redfield M. M., Tajik A. J.. Clinical utility of Doppler echocardiography and tissue Doppler imaging in the estimation of left ventricular filling pressures: a comparative simultaneous Doppler-catheterization study. Circulation 2000; 102(15):1788–1794PubMedGoogle Scholar
- 29.Poerner T. C., Goebel B., Unglaub P., Sueselbeck T., Strotmann J. M., Pfleger S., Borggrefe M., Haase K. K. Detection of a pseudonormal mitral inflow pattern: an echocardiographic and tissue Doppler study. Echocardiography 2003; 20(4):345–356. doi: 10.1046/j.1540-8175.2003.03040.x PubMedCrossRefGoogle Scholar
- 30.Poirier P., Bogaty P., Garneau C., Marois L., Dumesnil J. G.. Diastolic dysfunction in normotensive men with well-controlled type 2 diabetes: importance of maneuvers in echocardiographic screening for preclinical diabetic cardiomyopathy. Diabetes Care 2001; 24(1):5–10. doi: 10.2337/diacare.24.1.5 PubMedCrossRefGoogle Scholar
- 31.Rivas-Gotz C., Khoury D. S., Manolios M., Rao L., Kopelen H. A., Nagueh S. F.. Time interval between onset of mitral inflow and onset of early diastolic velocity by tissue Doppler: a novel index of left ventricular relaxation: experimental studies and clinical application. J. Am. Coll. Cardiol. 2003; 42(8):1463–1470. doi: 10.1016/S0735-1097(03)01034-9 PubMedCrossRefGoogle Scholar
- 40.Yellin E. L., Hori M., Yoran C., Sonnenblick E. H., et al. Left ventricular relaxation in the filling and nonfilling intact canine heart. Am. J. Physiol. (Heart Circ. Physiol.) 1986; 250:H620–H629Google Scholar