Myocardial function in children after fetal chemotherapy exposure. A tissue Doppler and myocardial deformation imaging study

Abstract

Chemotherapy and particularly anthracycline exposure are associated with acute and chronic cardiotoxicity. Few data exist on the effect of cardiac function after in utero exposure to maternal chemotherapy. Our recently published multicenter prospective study showed no significant changes in systolic function using conventional echocardiographic parameters. The purpose of this study was to further investigate whether early functional changes can be detected using tissue Doppler imaging (TDI) and two-dimensional (2D) speckle tracking echocardiography (STE). Sixty-two children (median/range age 1.7 (1-9.8) years) exposed to chemotherapy during fetal life were enrolled and compared to 62 age- and gender-matched controls. TDI velocities were measured at the basal interventricular septum (IVS) and right and left ventricular (LV) free walls. LV global longitudinal and circumferential systolic strains were derived using 2D STE. We found small but significant differences between the groups (patients versus controls) in LV fractional shortening [35 (29-46)% versus 39 (28-53)%, p < 0.001], LV ejection fraction [66 (57-79)% versus 70 (57-83)%, p < 0.001], LV posterior wall thickness z score [-0.15 (-2.32-1.81) versus -0.10 (-1.9-2.0), p < 0.001], and IVS thickness z score [-1.06 (-2.6-1.3) versus -0.5 (-2.1-1.7), p < 0.001]. No significant differences in TDI velocities or LV global strains were observed. Within the patient group, the cardiac functional parameters did not correlate to the number of cycles of anthracycline or the cumulative anthracycline dose. Children exposed to fetal chemotherapy have a lower normal fractional shortening and mildly lower left ventricular wall thickness. Tissue Doppler and strain measurements are within normal range and not statistically different from normal controls. The long-term implications of these findings will be further studied in this prospective cohort study.