Ratio of left atrial to left ventricular size: an anatomical marker of the diastolic left ventricular pressure-volume relationship.

Background: Classification of diastolic heart function is best defined by the degree of leftward and upward shift of the diastolic pressure-volume relationship (DPVR). Direct measurement of DPVR, however, requires invasive techniques. Increased left atrial (LA) size is a marker of left ventricular (LV) diastolic hypertension, and so, the LA/LV diameter ratio has the potential to mark the degree of upward and leftward shift in the LV-DPVR.