Fig. 1
From: The use of MRI in quantification of the atrial fibrosis in patients with rheumatic mitral disease
Measurement of left atrial volume from the area-length method using the apical four-chamber (a) and apical two-chamber (b) views. The length (L) is measured from the back wall to the line across the hinge points of the mitral valve (arrow). The shorter (L) from either the A4C or A2C is used in the equation