A case of right atrial myxoma--effect of large myxoma in the right atrium studied by M-mode and Doppler echocardiography.

Doppler profiles are rarely used to assess cardiac function that has been partially impaired by a sizeable myxoma in the right atrium or to evaluate the improvement caused by extirpation of the tumor. In a 54-year-old man with a large right atrial myxoma (6.5 x 5.5 x 4.0 cm) along with first-degree atrioventricular (AV) block, M-mode and pulsed Doppler echocardiography were used to evaluate the left ventricular systolic and diastolic function before and 1 month after surgical removal of the myxoma. End-diastolic left ventricular (LV) and left atrial diameters increased postsurgically from 47 to 51 mm and from 38 to 41 mm, respectively, while end-systolic LV remained unchanged. In the LV inflow pattern, peak early filling velocity (E) increased substantially (preoperative 31, postoperative 58 cm/sec), with no change in peak late filling velocity (A) (53 cm/sec), which gave a favorable E/A ratio (from 0.58 to 1.09). First-degree AV block resolved after tumor resection (PR interval: 0.23 vs 0.20 sec). Improved LV diastolic function associated with natural recovery from the myxoma was ascribed to the restoration of preload and recovery of systolic function. The results of this study show that removal of a large myxoma in the right atrium is important not only for preventing possible obstruction of the tricuspid orifice, eliminating pulmonary emboli, and maintaining systolic function, but also for restoring LV diastolic function.