Using traditional measurements of the left atrial diameter to predict the left atrial volume index

BACKGROUND: Left atrial enlargement by echocardiography is associated with adverse cardiovascular outcomes, yet the best method for assessing left atrial size has not been established. We sought to correlate the traditional left atrial diameter (LAD) measured in the parasternal view with the recently characterized left atrial volume index (LAVI). METHODS: 100 routine clinical patients who received a transthoracic echocardiogram for customary indications were studied. The LAD and LAVI were measured in each patient. RESULTS: The mean LAVI was 32.8 milliliters per square meter (ml/m(2)) and the LAD was 46.8 millimeters (mm). LAD > 4.7 centimeters (cm) was predictive of LAVI > 32 ml/m(2) (P < 0.001; OR 17.33; 95% CI = 5.96-50.44). CONCLUSION: LAD > 4.7 cm via the traditional method can be used to indicate left atrial enlargement. However, a LAD < or = 4.7 cm does not correlate well with the LAVI, and in such patients, extreme caution should be employed when using the LAD to estimate cardiac prognosis.