Huge Left Atrial Myxoma Presenting as Pulmonary Embolism on a CT Pulmonary Angiogram

Atrial myxomas are the most common benign primary cardiac tumours. Despite their benign nature, they can significantly increase morbidity and mortality. The majority occur in the left atrium, although familial myxoma syndromes may present in atypical locations. Patients may present with symptoms related to intracardiac obstruction or embolic phenomena or remain asymptomatic. A 76-year-old woman presented to her general practitioner with shortness of breath and features consistent with pulmonary embolism. Computed tomography pulmonary angiography (CTPA) revealed a large filling defect within the left atrium. Subsequent transthoracic echocardiography confirmed the presence of a large left atrial myxoma attached to the atrial base. Intraoperative transoesophageal echocardiography (TOE) further demonstrated the attachment site. The patient underwent successful surgical excision via a median sternotomy and trans-septal approach. Several modalities are available for diagnosing left atrial myxomas, with TOE providing excellent diagnostic accuracy. However, CTPA can also detect atrial myxomas with the additional advantage of being non-invasive. While TOE remains the preferred modality for diagnosis of left atrial myxomas, CTPA can be a useful complementary investigation. It may help distinguish atrial myxomas from pulmonary embolism, as demonstrated in this case, while offering the added benefit of being non-invasive. It is extremely useful for differentiating atrial myxomas from pulmonary embolism, as discussed in the case, with the added benefit of being non-invasive.