An 83-year-old woman underwent vascular salvage surgery for extensive embolic disease in her lower limbs. A transoesophageal echocardiography scan revealed a 4 × 2.5 cm, echogenic, ovoid, pedunculated, mobile mass attached to the interatrial septum (Panels A and B; see Supplementary data online, Movies S1 and S2) consistent with atrial myxoma. However, colour-flow Doppler echocardiography and contrast echocardiography (Definity contrast microbubbles, Lantheus Medical Imaging, North Billerica, MA, USA) showed an absence of vascular channels through the mass and no evidence of myxoma blush (Panels C and D; see Supplementary data online, Movies S3 and S4). Cardiac catheterization also showed no tumour blush (Panel E). The mass was resected and appeared myxomatous and mobile in situ (Panel F). However, histological sampling showed no evidence of myxoma, with the findings consistent with early organizing thrombus (secondary to permanent atrial fibrillation). The size, site, and specific features of this unusual-appearing thrombus led to its misdiagnosis as myxoma. Similar cases of a thrombus mimicking a myxoma have been reported, highlighting the need for diagnostic tools to separate between the two. This case demonstrates the potential value of tumour perfusion imaging with Definity contrast echocardiography as well as colour-flow Doppler and coronary angiography. All these modalities suggested the avascular nature of the tumour, as myxomas are mesenchymal tumours with vasoformative tendencies.
Conflict of interest: none declared.
Supplementary data are available at European Heart Journal—Cardiovascular Imaging online.
