Contrast transesophageal echocardiographic demonstration of coronary artery fistula within left atrial appendage thrombus in mitral stenosis.

Coronary neovascularization and fistula formation arising from the left circumflex artery demonstrated by coronary angiography is a specific sign for the presence of left atrial appendage thrombus in patients with mitral stenosis. However, the fistula drainage site in the left atrium in relation to the thrombus cannot be ascertained by the angiographic method. We performed transesophageal echocardiography simultaneously with coronary angiography in five patients with severe mitral stenosis and left atrial appendage thrombus. The angiography showed coronary neovascularization and fistula arising from the left circumflex artery in three patients. In these three patients, the transesophageal echocardiography confirmed the presence of a coronary fistula by identifying contrast exuding from the surface of the thrombus. Thus we have shown for the first time the usefulness of contrast transesophageal echocardiography in imaging the exact drainage site of coronary artery fistula from left atrial appendage thrombus.