The wall-thinning to transmitral flow-velocity relation:: Derivation with in vivo validation

Motion of the endocardial surface in diastole is the resultant effect of wall thinning. Endocardial wall motion to transmitral flow (Doppler E-wave) relations that predict wall thinning are derived using conservation of myocardial volume, two simplified (spatiotemporally homogeneous) left ventricular (LV) geometric models and the constant-volume pump attribute of the heart. For validation, model-predicted vs. color hi-mode recorded maximum rate of wall thinning was compared in (n = 15) normal controls. Excellent agreement for both models (r = 0.84, r = 0.86) was observed. For abnormal LV function (n = 15), model-predicted vs. M-mode recorded maximum rate of wall-thinning correlated poorly (r = -0.28, r = -0.22). We conclude that, in normal ventricles, the Doppler E-wave and wall thinning are related through the constant-volume attribute of the heart and its geometry. Pathologic cases are governed by the same principles, but the filling to wall-thinning relation is altered by spatiotemporal inhomogeneities in geometry and wall motion. (E-mail: sjk@wuphys.wustl.edu) (C) 2002 World Federation for Ultrasound in Medicine Biology.