Myocardial 2D Strain During Long-Term (>5 Years) Follow-Up of Childhood Survivors of Acute Lymphoblastic Leukemia Treated With Anthracyclines.

Anthracycline-induced cardiotoxicity can lead to clinical and subclinical heart failure. Decrease of global longitudinal strain is a predictor for heart failure. Early detection of subclinical cardiotoxicity is crucial for timely intervention and prevention of further progression. Cardiac function of 41 survivors of childhood acute lymphoblastic leukemia (ALL) was assessed. Values of cardiac troponin T, N-terminal-pro-brain natriuretic peptide, conventional and myocardial 2D strain echocardiography were measured before (T = 0), during (T = 1, cumulative dose of 120 mg/m), shortly after (T = 2) and long after anthracycline treatment (T = 3, ≥5 years after anthracycline exposure). Cardiac function of survivors at the latest follow up was compared with 70 healthy age-matched controls. None of the survivors showed clinical signs of cardiac failure at T = 3. Strain values decreased during anthracycline treatment and an ongoing reduction was seen at the latest follow-up (T = 3) with preserved cardiac function (normal ejection fraction and shortening fraction). At T = 1, a relative reduction in longitudinal strain (≥10% compared with baseline) was observed in 38% of the survivors, which increased to 54% at T=3. ALL survivors showed significantly lower conventional and myocardial 2D strain values, especially strain rate, compared with healthy age-matched controls. At T = 3, we did not find any abnormal cardiac troponin T levels. Six percent of the survivors showed abnormal N-terminal-pro-brain natriuretic peptide levels. This prospective study showed an ongoing reduction of 2D myocardial strain and strain rate, with preserved left ventricular ejection fraction (≤10% decrease compared with baseline) in asymptomatic ALL survivors at late follow-up.