Transseptal biopsy of a left atrial mass with 3-dimensional transesophageal echocardiographic guidance

A 31-year-old man presented with a large cardiac mass that originated from the basal posterior left atrial wall and occupied most of the dilated atrium. Minimally invasive studies yielded inconclusive results, but the patient was considered at high risk for an open cardiac biopsy due to the size of the mass. To establish a tissue diagnosis for definitive treatment, we performed a transseptal cardiac biopsy guided by 3-dimensional transesophageal echocardiography. We thereby determined that the mass was a primary left atrial sarcoma. To the best of our knowledge, this is the first report concerning the use of 3-dimensional transesophageal echocardiography for biopsy of a left atrial mass.

Pseudo-false-positive exercise treadmill testing caused by systolic anterior motion of the anterior mitral valve leaflet

Subendocardial ischemia as indicated by electrocardiography during exercise, in association with severe systolic anterior motion of the anterior mitral valve leaflet without left ventricular hypertrophy, has not been well described. We report the case of a 42-year-old man who presented with symptoms of exertional angina and 2-mm ST depression on treadmill electrocardiography but had a normal perfusion scan and coronary angiogram. Initially the negative angiographic results caused us to regard the treadmill results as false-positive. Subsequently, low-dose dobutamine echocardiography showed severe systolic anterior motion of the anterior mitral valve leaflet with a >144-mmHg left ventricular outflow tract gradient; we then recognized the original treadmill results to be pseudo-false-positive. Electrocardiographic changes in association with the above-described motion of the anterior mitral valve leaflet and increased left ventricular outflow tract gradient were verified by use of treadmill and supine bicycle stress echocardiography.