An accurate and simplified method to calculate left ventricular (LV) ejection fraction (EF) derived from the ellipsoidal formula for LV volume calculation is described. The LV minor axis (D) is obtained from the average of three equidistant LV diameters at end-diastole (Ded) and end-systole (Des), and the shortening fraction of D2 (%δD2) calculated as (D2ed – D2es)/D2ed. EF is calculated as EF = [ δD2 + ([1 – δD2] × δL)] × 100, where δL = the shortening fraction of the long axis. The coefficient of correlation between the EF by this method and the EF derived from measurements of LV volumes with the area-length method was 0.98, SEE = 3.57% (n = 50). No significant over- or underestimation was observed according to the regression equation Y = 0.922x + 0.82. Thus, this simplified method allows accurate LVEF calculation without the need for planimetry of LV area.