LA mass shadow after removal of LA myxoma.

Inverted left atrial tissue is mostly identified when the heart is empty while coming off bypass. During echocardiography a new, echodense mobile mass in the left atrium without attachment is visualized. Such a picture can easily produce not only confusion in the diagnosis but also mitral valve obstruction, hemodynamic instability, and a possibility of appendage necrosis. Inability to identify such inverted tissue can lead to unwanted interventions with additional cardiopulmonary bypass time.

A 30-year-female patient presented with history of shortness of breath on moderate exertion. Transthoracic echocardiography showed large left atrial (LA) mass bouncing in left atrium and protruding into left ventricle in diastole. All the coagulation parameters and thrombophilic profile of the patient were normal. Presuming the mass to be LA myxoma, the patient was scheduled for surgery for removal of LA myxoma. Intraoperative transesophageal echocardiography (TEE) revealed a large, homogenous, mobile LA mass with fimbricated appearance measuring 4.2 cm × 3.8 cm, with stalk attached to interatrial septum protruding into LV cavity during diastole (Fig. 1). Moderate eccentric mitral regurgitation was also observed. After establishing cardiopulmonary bypass and cardioplegic arrest, tumor along with its attached stalk was removed and mitral valve annuloplasty was also done. The defect in atrial septum was closed with autologous pericardial patch. While coming off cardiopulmonary bypass, TEE revealed echodense shadow mimicking small LA mass just above mitral valve (Fig. 2, Fig. 3). What was this shadow – the remnant or second LA myxoma which went unnoticed during surgery or anything else?

Fig. 1

Transesophageal echocardiography midesophageal 4-chamber view showing left atrial myxoma.

Fig. 2

Transesophageal echocardiography midesophageal 4-chamber view showing inverted left atrial tissue appearing as echodense mass.

Fig. 3

Transesophageal echocardiography midesophageal long-axis view showing inverted left atrial tissue appearing as echodense mass.

The surgeon examined the lateral wall of left atrium and found left atrial tissue inverted into LA. Echodense shadow in LA was actually because of inversion of LA tissue. During weaning from bypass, this inverted LA part gradually vanished as LA started filling (Fig. 4). Inverted left atrial tissue is mostly identified when the heart is empty during coming off bypass.1, 2 Echocardiography gives the picture of new, echodense mobile mass in the left atrium without attachment. Such a picture can easily produce not only confusion in the diagnosis but also mitral valve obstruction, hemodynamic instability, and possibility of appendage necrosis.1, 3 Inability to identify such inverted tissue can lead to unwanted interventions with additional cardiopulmonary bypass time.4, 5 Introperatively recognized inverted tissue can be everted with traction and ligated. Postoperatively detected inversion can be treated conservatively or reoperation has also been reported. In the present case, inversion got spontaneously corrected as LA started filling. Awareness of possibility of inverted tissue can help resolve the diagnosis and suggest its treatment.

Fig. 4

Transesophageal echocardiography midesophageal 4-chamber view showing disappeared left atrial mass shadow.

Conflicts of interest

The authors have none to declare.