Two-dimensional speckle-tracking strain detects subclinical cardiotoxicity in older patients treated for acute myeloid leukemia.

BACKGROUND: Patients with acute myeloid leukemia (AML) are surviving longer. There are no data on changes in myocardial mechanics from standard of care low-dose anthracycline-based induction chemotherapy in older patients with AML. The aim of this study was to demonstrate the potential utility of strain imaging in detecting early changes in left ventricular function in this patient population after induction chemotherapy.

METHODS: Thirty two patients enrolled in the ECOG-ACRIN E2906 study (cytarabine and daunorubicin vs clofarabine [Genzyme/Sanofi]) from 2011 to 2014 were evaluated retrospectively. Two-dimensional transthoracic echocardiography (TTE) imaging with Doppler and two-dimensional speckle-tracking echocardiography (2DSTE) using EchoInsight software (Epsilon imaging) were performed before and after induction chemotherapy.

RESULTS: Eighteen patients received cytarabine and daunorubicin (7 + 3) and 14 received clofarabine. The clofarabine group was older than the 7 + 3 cohort (67.8 ± 4.0 vs 63.7 ± 3.8, P = .007). There were no other significant differences in cardiac risk factors between groups. The 7 + 3 group had a decrease in average peak systolic global longitudinal (-19.1 ± 2.8 to -17.2 ± 3.0, P = .01) and circumferential strain (-29.4 ± 6.3 to -23.9 ± 4.3, P = .011). These changes were not demonstrated in the clofarabine group and were not associated with a decline in left ventricular ejection fraction (LVEF).

CONCLUSIONS: In older AML patients, standard cytarabine and daunorubicin chemotherapy causes early changes in global longitudinal and circumferential strain not seen with clofarabine therapy. These findings demonstrate subclinical left ventricular dysfunction after exposure to low cumulative doses of anthracycline-based induction chemotherapy and may help us better identify those patients at risk for adverse long-term cardiovascular outcomes.