Incidence and clinical significance of interatrial shunting in patients with atrial septal aneurysm detected by contrast transesophageal echocardiography.

The prevalence of atrial septal aneurysm (ASA) in a general referral population of patients was investigated by use of transthoracic (TTE) and transesophageal echocardiographies (TEE). Contrast TEE was performed to detect interatrial shunting in patients with ASA. In this population, the prevalence of ASA as determined by TTE was 0.47% (24/5,079), and 0.78% (40/5,079) by TEE. Of these 40 patients 16 (40%) were judged to be normal by TTE. Of the forty patients who were positive for ASA, 50% demonstrated interatrial shunting (atrial septal defects, 10; patent foramen ovale, 10). The authors concluded that TEE is of significant value in detecting the presence of ASA and associated cardiac abnormalities. Contrast TEE further enhances the detection of interatrial shunting in patients with ASA.