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Blood Flow Patterns in the Heart: Normal

Normal blood flow is usually laminar, characterized by a smooth homogeneous color pattern. Aliasing will occur if the velocities exceed the Nyquist limit. You can image normal blood flow from any window that lets you see both proximal and distal to a valve. Normal Blood Flow: Normal Blood Flow Through the Mitral Valve You can see blood flow through the mitral valve (MV) from the parasternal, apical and subcostal views. Normal left ventricular inflow occurs in diastole, as blood moves from the left atrium to the left ventricle. This parasternal long-axis view, frozen in diastole, shows normal left ventricular inflow with an enhanced velocity map. The red flow area represents flow toward the transducer with the lower velocities, represented by darker reds, occur around the edges of the jet. The small patch of blue at the tip of the posterior MV leaflet represents the quick motion of the valve, which has moved away from the transducer. The red in the right ventricle (RV) represents blood flow moving in the right ventricular outflow tract (RVOT). This apical four-chamber view shows normal diastolic blood flow through the MV. An enhanced velocity map has primarily red colors due to the flow toward the transducer. Oranges and yellows indicate the higher velocities in the center of the jet. The smooth progression from red to yellow indicates laminar blood flow. Though it looks significantly different from the picture above, the diastolic left ventricular inflow depicted in this apical four-chamber view is normal. This image also has an enhanced velocity map. The smooth progresion from red to blue indicates laminar blood flow.