A bedside ultrasound sign of cardiac disease: the left atrium-to-aorta diastolic diameter ratio.

Purpose: This study evaluated a simple ultrasound method to detect left atrial (LA) enlargement by comparing the diameters of the LA and aortic root.

Procedures: The LA and aortic diameters, the LA volume index (LAVI), and significant echo findings were analyzed in 101 consecutive echocardiograms. Mean LAVI and the prevalence of an abnormal echo were compared between groups in which the ratio of the LA diameter to aortic diameter in diastole was >1 vs < or = 1.