Résumé
Myxomas are rarely associated with congenital cardiac anomalies. We report a case of a young female presenting with symptoms of atrial myxoma but having co-existing ASD visualized on 64 slice multidetector computed tomography [MDCT] prior to cardiac surgery. Patient had a successful resection of biatrial myxoma and ASD repair. This case is unique as the myxoma originated from the inferior margin of the ASD straddling the inferior limbus. Over the years due to the left to right shunt at the ASD, the myxoma was initially prolapsing and oscillating between the two atria. As it grew larger it obliterated the ASD and got stuck in the right atrium [RA] and continued to grow giving false impression of a right atrial mass. Multi detector computed tomography is an alternative diagnostic modality to the gold standard transesophageal echo-cardiograph for detection of an ASD in the presence of atrial myxoma. Biatrial myxoma with associated atrial septal defect has optimal postoperative results