Flow propagation. Top: colour M-mode from normal subject. The picture shows early filling (E) and atrial systole (A). The two phases of early filling phase I or column propagation and phase II or vortex propagation described by Steen & Steen (12) are also visible. Measurement of column flow propagation as the slope ΔL/Δt is shown. Middle: from a patient with delayed relaxation with normal LV diameter and EF. High flow velocity propagation of phase I, evidenced by the upright column is seen. In addition there is very little phase II propagation, indicating a narrow ventricle during early filling. Bottom: from a patient with slightly dilated LV of 65 mm and EF of 45%. The main velocity propagation is phase II, vortex propagation with a low propagation velocity. Phase I is hardly discernible.