Mitral prosthetic replacement in small left atria

An exceptionally giant left atrial myxoma: a case report and literature review

Background

Cardiac myxomas are considered the most common benign heart tumours. The clinical manifestations mainly depend on the size of the tumour. They usually vary from asymptomatic, mild non-specific symptoms, to severe obstructive cardiac and systemic findings. We describe herein a significantly large left atrial myxoma in a patient misdiagnosed with respiratory asthma.

Case summary

A 54-year-old lady, was diagnosed previously with asthma, presented with a history of dyspnoea on exertion, palpitations, and mild peripheral oedema. Chest X-ray suggested pulmonary congestion. Due to high suspicion of cardiac issues, transthoracic echocardiography was done revealing giant left atrial mass. Consequently, the mass was approached and excised surgically through the inverted T biatrial incision. Grossly, the mass measured 10 × 8 × 6 cm, and it had a smooth surface and was filled with gelatinous material. The histopathology confirmed benign myxoma without malignant features.

Discussion

Our article mainly focuses on the diagnostic challenges of a patient with atrial myxoma. The major discrepancy between the tumour size and the severity of the patient’s symptoms should draw physicians’ attention to consider atrial myxoma over a long list of differentials, in order to take immediate action to reduce the mortality and improve the overall prognosis.

Inverted T-shaped biatral incision for large left atrial myxoma

Various surgical approaches for a left atrial myxoma have been developed to provide optimal exposure and to allow radical excision of the tumor. However, when a myxoma occupies most of the left atrium, it is difficult to remove the friable tumor without fragmentation. The inverted T-shaped biatrial incision is a modified transseptal approach to expose the mitral valve. Using this approach, we can extirpate even a huge tumor without fragmentation. A horizontal incision of the left atrium is made, followed by a vertical incision into the right atrium. A careful assessment is made as to whether or not this biatral approach is sufficient to remove the large left atrial myxoma. If exposure is considered inadequate, the interatrial groove is divided. The incision is continued distant from the pedicle, if possible, more than 5 mm away. The tumor is excised, including tissue around the base of the tumor, with wide margins.

A new technique for performing mitral valve repair in a small left atrium

A simple approach for exposing a difficult mitral valve within a small left atrium is described herein through the report of case. Mobilization of the superior vena cava with direct venous cannulation and extended dissection of the interatrial groove provide excellent mitral valve exposure, even in patients with a small left atrium.

Optimal approach to the mitral valve: dissection of the interatrial groove

Surgical exposure of the mitral valve has challenged surgeons for more than 30 years. Many ingenious, but often complex approaches have been devised during this time. Using the dissection of the interatrial groove to bring the left atrial incision more anterior and medial, we have achieved excellent exposure in more than 300 mitral valve procedures. This simple technique does not lengthen the procedure and is not associated with an increased risk of either early or late morbidity.