<P> Left atrial enlargement (LAE) or left atrial dilation refers to enlargement of the left atrium (LA) of the heart, and is a form of cardiomegaly . </P> <P> In the general population, obesity appears to be the most important risk factor for LAE . LAE has been found to be correlated to body size, independent of obesity, meaning that LAE is more common in people with a naturally large body size . Also, a study found that LAE can occur as a consequence of atrial fibrillation (AF), although another study found that AF by itself does not cause LAE . The latter study also showed that the persistent type of AF was associated with LAE, but the number of years that a subject had AF was not . </P> <P> Obstructive sleep apnea (OSA) may be a cause of LAE in some cases . When an OSA event occurs, an attempt is made to breathe with an obstructed airway and the pressure inside the chest is suddenly lowered . The negative intrathoracic pressure may cause the left atrium to expand and stretch its walls during each OSA event . Over time, the repetitive stretching of the left atrium may result in a persistent left atrial enlargement . </P> <P> Left atrial enlargement can be mild, moderate or severe depending on the extent of the underlying condition . Although other factors may contribute, left atrium size has been found to be a predictor of mortality due to both cardiovascular issues as well as all - cause mortality . Current research suggests that left atrium size as measured by an echo - cardiograph may have prognostic implications for preclinical cardiovascular disease . However, studies that have found LAE to be a predictor for mortality recognize the need for more standardized left atrium measurements than those found in an echo - cardiogram . </P>

What is the treatment for left atrial enlargement