Bett J H, Graff R F, Stafford E G, Dryburgh L
Aust N Z J Med. 1978 Aug;8(4):428-30. doi: 10.1111/j.1445-5994.1978.tb04917.x.
M-mode echocardiography displayed abnormal echoes in the left atrium and posterior to the mitral leaflets in a child with severe heart failure. Cor triatriatum was demonstrated by angiography and cured by surgical excision. Subsequent echo studies no longer showed the abnormal structure.