Search

Elevated tricuspid regurgitant velocity (TRV) ≥2.5 m/s is a predictor of disease severity in adults and children with sickle cell anemia (SCA), but how disease-modifying therapies (DMTs) affect this biomarker is incompletely understood. We investigated the effect of DMTs on TRV elevation in children. In a prospective single-center study, 204 subjects with HbSS or HbSβ0 thalassemia (mean age, 10.6 years; range, 5-18) had echocardiograms with assessment of TRV, with repeat evaluations after 2 years of observation. One-hundred and twelve participants received DMTs (hydroxyurea, n = 72; monthly erythrocyte transfusions, n = 40), 58 did not receive any DMT, and 34 were begun on hydroxyurea during this observation period. In the entire cohort, an increase in hemoglobin of 1.0 g/dL was associated with a 0.03-m/s decrease in TRV (P = .024), and a decrease in absolute reticulocyte count of 1.0 × 106/mL was associated with a 0.34-m/s decrease in TRV (P = .034). Compared with baseline, hydroxyurea exposure (continuous or newly started) was associated with an average 5% decline in mean TRV at the 2-year evaluation. Among participants newly started on hydroxyurea (mean treatment duration 1.2 ± 0.6 years), an increase in hemoglobin of 1.0 g/dL was associated with a 0.06-m/s decrease in TRV (P = .05). We conclude that hydroxyurea therapy may mitigate TRV elevation in children with SCA, possibly as a result of a reduction in hemolysis and improvement in anemia., (© 2021 by The American Society of Hematology.)

Cardiac disease is the primary cause of death in sickle cell disease (SCD). Right and left ventricular global longitudinal strain (RVGLS, LVGLS) are early markers of systolic dysfunction but are not well investigated among children with SCD. One hundred and forty-three patients with HbSS or HbSβ 0 -thalassaemia (median age 11 years, range 5-19 years) and 71 controls matched for age and sex were compared. RVGLS and LVGLS were measured and compared with conventional measures of echocardiography and markers of haemolysis and inflammation. RVGLS was higher in children with SCD than in controls (-25·72% ± 3·45% vs. -24·54% ± 2·41%, P = 0·005); LVGLS was not different. RVGLS decreased with older age in children with SCD (ρ = 0·338, P < 0·001) but not among controls. Decreased RVGLS was associated with increased left atrial end diastolic volume (ρ = 0·181, P = 0·04); RVGLS increased with cardiac output (r = -0·279, P = 0·01). RVGLS and LVGLS were not associated with disease-modifying therapies, degree of anaemia or haemolysis markers. Elevated RVGLS may indicate an early RV compensatory mechanism in response to upstream myocardial insults and elevated cardiac output. Global longitudinal strain may serve as an early marker of altered myocardial function in children with SCD., (© 2018 British Society for Haematology and John Wiley & Sons Ltd.)