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Figure 1 Diagram of mitral filling pattern, mitral annulus velocities, and corresponding four-chamber view during early diastole. (Left side) Left ventricular (LV) diastole is characterized by swift myocardial relaxation and elastic recoil. As a result, normal transmitral flow is characterized by a prominent and rapid early (E) filling wave (arrow) due to passive suction, and by a diminutive late (A) atrial filling wave due to atrial contraction. During diastole, the LV expands longitudinally resulting in a descent of the mitral valve annulus (open arrow) as opposed to the relatively fixed apex. As the velocity of the earliest diastolic motion of the mitral valve annulus (Ea) relates to the rate of myocardial relaxation, Ea is prominent in normal hearts. (Right side) When diastolic dysfunction occurs, myocardial relaxation is impaired; LV pressure falls slowly, reducing early transmitral driving pressure. As a result, E is decreased (arrow), and, because of increased atrial preload, A is increased. Due to decreased myocardial relaxation velocity, Ea is reduced (open arrow). As disease progresses, LV compliance also becomes impaired, and LV filling becomes dependent on increased left atrial (LA) or filling pressure (dashed arrow). This results in an increased E. As the underlying impaired relaxation is masked and because the pattern resembles the normal filling pattern, it is called pseudonormalized pattern. Combining E, which is dependent on both filling pressure and myocardial relaxation, with Ea, which is mainly dependent on myocardial relaxation, allows differentiation of a normal from a pseudonormal signal and better evaluation of filling pressures (see equation). E = peak mitral velocity in early diastole; Ea = early diastolic tissue velocity.
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