Fig. 2From: Reliability of three-dimensional color flow Doppler and two-dimensional pulse wave Doppler transthoracic echocardiography for estimating cardiac output after cardiac surgeryCO assessment using 3DCF transthoracic echocardiography. 3DCF images were obtained in the apical long axis view (panel a). With the aortic valve (AV) at the center (green dot line in panel b and c), the reference images were rotated and adjusted to clearly show the region of interest from the left ventricular outflow tract to the proximal part of the aorta; systole, diastole, timing of AV opening (AVO) and closing (AVC) were automatically recognized by the software according to the ECG (panel d); panels a and e show that the 3D volume color flow passes vertically through the sampling plane (the yellow line in panels b and c, the yellow plate in panel a), and the size of the sampling plane is just big enough for all of the outflow color signals to pass through; panel d shows the flow–time curves of three consecutive cardiac cycles generated by the softwareBack to article page