Marked recovery of cardiac function by chemotherapy and autologous stem cell transplantation of a patient with heart failure with preserved ejection fraction due to primary amyloid light-chain amyloidosis: a case report

Abstract

Background Cardiac involvement of amyloid light-chain (AL) amyloidosis is strongly associated with poor outcome, but the early detection of cardiac involvement of AL amyloidosis can be challenging. Case summary We present a case of 49-year-old-female with heart failure with preserved ejection fraction. Echocardiography revealed normal left ventricular (LV) ejection fraction of 63% and an enlarged left atrium with a left atrial volume index (LAVI) of 54 mL/m2. Mild LV hypertrophy with an interventricular septum of 12.3 mm and posterior wall thickness of 11.0 mm was observed, and Doppler-derived LV diastolic filling showed a restrictive filling pattern. The conventional echocardiographic findings did not unequivocally indicate typical cardiac amyloidosis, but global longitudinal strain (GLS) was as low as 14.2%, and an apical sparing pattern was observed with relative apical longitudinal strain of 1.11. Finally, the patient was diagnosed as primary AL amyloidosis including histological examination of the endomyocardial specimen. After treatment with a regime of bortezomib and dexamethasone followed by high-dose melphalan followed by autologous peripheral blood stem cell transplantation (auto-PBSCT), Doppler-derived LV diastolic filling improved to normal filling pattern, and left atrial size had also decreased with an LAVI of 31 mL/m2. Moreover, GLS improved to 19.8%, and the apical sparing pattern had disappeared with relative apical longitudinal strain of 0.62. The patient has been asymptomatic during 18-month follow-up after auto-PBSCT, and recovered LV function has been maintained. Discussion An earlier diagnosis of cardiac amyloidosis by using apical sparing may therefore allow for earlier treatment intervention for AL amyloidosis.