Discussion
The cardiovascular manifestations of patients with left atrial myxoma strongly depend on tumor size and localization2. The patient in the present case showed respiratory failure and acute pulmonary edema as the initial signs, which were probably caused by an acute enlargement of the myxoma due to an internal hemorrhage. Unfortunately, the diagnosis of myxoma was overlooked during the initial evaluation with bedside ultrasound. The probable reason is that emergency physicians have less training in ultrasonographic image acquisition and interpretation compared with sonographers or skilled physicians that are trained in echocardiography. In addition, it is challenging to differentiate myxomas from valve vegetations and left atrial clots under severe tachycardia. Therefore, it is important to consider cardiac myxoma in the differential diagnosis of respiratory failure and acute pulmonary edema in emergency departments, especially for those patients without a history of heart disease, as early consultation with experienced sonologists.
Despite early positive internal medicine treatment, the patient’s condition rapidly progressed to cardiopulmonary failure. At this time, it was discovered that the giant atrial myxoma was the cause and had to be operated immediately; however, the local hospital was unable to carry out the operation. As a result, VAV-ECMO was performed as an alternative intervention. ECMO is a rescue therapy that can stabilize patients with severe hypotension, with or without respiratory failure. In cardiology, the main indications for ECMO include cardiac arrest, cardiogenic shock, post-cardiotomy shock, refractory ventricular tachycardia, and acute management of complications of invasive procedures3. The use of ECMO as a bridge between the transfer and perioperative periods of patients with acute heart failure in cardiac surgery has been shown to be a viable strategy in the recent years; however, it is rarely reported for surgical treatment of atrial myxoma4. Therefore, the case suggests that atrial myxoma is prone to sudden death, and once diagnosed, it should be operated as soon as possible under the guidance of ECMO if necessary.