Left atrial myxoma: false negative echocardiographic findings in a tumor demonstrated by coronary arteriography.

A report of left atrial myxoma discovered at coronary arteriography by virtue of unusual tumor "vascularity" is presented in which establishing the diagnosis by means of echocardiography proved difficult. The difficulty may have been due to the highly vascular nature of the tumor with resultant loss of the acoustic reflectivity required for echocardiographic demonstration. Previous cases in which left atrial myxomas have shown arteriographically demonstrable "tumor vascularity" are reviewed.