Statistics from Altmetric.com
The cause of adult T cell leukaemia (ATL)1 is human T cell leukaemia virus type I (HTLV-I), which was discovered in 1980.2 This virus is endemic in southwestern Japan, the Caribbean, Africa, and South America. However, cardiac valve involvement by ATL cells is extremely rare3 and there is no previous echocardiographic evidence for this involvement. We present serial echocardiographic observations in a patient with chronic ATL in whom leukaemic involvement of the mitral valve showed pronounced improvement after chemotherapy.
A 58 year old woman was admitted because of two previous episodes of acute heart failure. On examination, generalised skin eruptions and lymphadenopathies were noted. Third and a fourth heart sounds (gallop rhythms) and a grade 3/6 pansystolic murmur were present at the apex. Transthoracic echocardiography showed extensively thickened mitral and tricuspid valves with moderate regurgitations. The left ventricle was mildly dilated with reduced wall motion. Transoesophageal echocardiography showed an echogenic endocardial lesion at the left atrial wall and appendage, which extended continuously to the bizarre mitral valve abnormality (fig 1). Gallium scintigraphy showed a significant cardiac accumulation.
Serological tests were positive for anti-HTLV-I antibodies by particle agglutination and immunofluorescence. ATL cell infiltration was found in lymph node and skin biopsy specimens. Leukaemic cells from the lymph node expressed T cell markers (CD2+, CD3+, CD4+, CD7+, CD8-, and HLA-DR+). Together with echocardiographic and gallium scintigraphic findings, valvar invasion of tumour cells was suspected, possibly with myocardial involvement. Combination chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisolone was started. After three chemotherapy sessions, the lesions in the mitral and tricuspid valves responded favourably with obvious reduction in thickness and improved flexibility in leaflet motion (fig 1). Repeated gallium scintigraphy demonstrated disappearance of the abnormal cardiac accumulation.
Despite these improvement the patient had an another episode of acute heart failure 10 months later and underwent mitral and aortic valve replacements. At surgery, the mitral valve was extremely thickened. Similar whitish thickenings were found in the left atrial wall and in the basal left ventricular wall. The diagnosis of valvar ATL cell infiltration was confirmed by histopathological examination of a surgically excised mitral valve.
This is the first echocardiographic documentation of cardiac valve involvement in ATL. The serial morphological changes of valvar lesions in response to chemotherapy have not been reported previously. This case has two important messages: first, it may at times be difficult to differentiate echocardiographically leukaemic valvar invasion from myxomatous valvar changes seen in patients with mitral valve prolapse, not only because of the similarity of echocardiographic valvar features but also because of the rarity of leukemic valvar invasion; second, it is important to raise the possibility of involvement of the myocardium by ATL cells when the echocardiographic valvar abnormality is detected in the presence of positive HTLV-I serology, as myocardial involvement is probably more common as suggested by this case as well as by previous pathological reports.4 5 We propose ATL associated cardiac valvulopathy as one of the important signs of cardiac invasion by ATL cells that may be detectable echocardiographically.