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.