Pulmonary hypertension in sickle cell disease children under 10 years of age

Abstract

SummaryDespite the finding of elevated Tricuspid Regurgitant Velocity (TRV) in children below 5 years of age, the prevalence and evolution of Pulmonary Hypertension (PH) in young children with sickle cell disease (SCD) are unclear. In order to identify predictive factors of precocious PH development, SCD children ‡3 years old, at steady state, underwent annual echocardiography and Tissue Doppler Imaging (TDI). Patients receiving chronic transfusion were excluded. Thirty-seven of seventy-five patients were ‡3 years, with measurable TRV. In our young population (mean age 6AE2 years) of mainly African, HbS/HbS patients, 8/37 (21AE6%) had TRV ‡2AE5 m/s, 8% being only 3 years old. Significant correlation was found between precocious TRV elevation and high platelet and reticulocyte counts and frequent acute chest syndromes (ACS). In multivariate analysis, ACS was the only variable predicting TRV ‡2AE5 m/s. TDI of the 37 patients showed signs of diastolic dysfunction of the left ventricle. At follow-up all eight patients with high TRV displayed further increase and seven more developed TRV ‡2AE5 m/s. PH seems to begin in children earlier than expected. Factors involved in its early onset might be different from the ones causing its development in older children or adults. African children might benefit from early screening and re-assessment once a year.

Tricuspid regurgitant jet velocity and hospitalization in Tanzanian children with sickle cell anemia

“…In this first report of a large population of children with SCA resident in Africa, the prevalence of high TRV is similar to that observed in the US and Europe, [5][6][7][8][9]12 despite the fact that study subjects had had no hydroxyurea exposure, fewer blood transfusions (cross-sectional data from same aged children in the Muhumbili Sickle Cohort: 80% none, 13% 1, 6% 2-5; Makani and Cox, unpublished data, 2013) and higher burden of infectious diseases. The high TRV cut off generated from our controls was similar to that from American age-matched controls (>=2.6 m/s).…”

“…This is in contrast to the PUSH study 5,14,15 in which all assessed hemolytic markers were associated with TRV over 2.6 m/s (unconjugated bilirubin not reported) but in line with two smaller studies. 7,9 In a study of adolescent and adult Nigerian patients, combined 16 LDH, but not total bilirubin (unconjugated bilirubin not reported) was associated with elevated TRV. We did not have reticulocyte counts available and could not calculate a hemolysis index.…”

“…Elevated tricuspid regurgitant velocity (TRV) measured by echocardiogram predicts death in adult sickle cell anemia (SCA) [1][2][3][4] and occurs in children, [5][6][7][8][9] although etiology and association with survival and complications requiring hospitalization are unknown. In children, hemolysis is associated with TRV in some 5,6 but not all 7,9 studies.…”

Hematopoietic Stem Cell Transplantation for Sickle Cell Disease: Current Practice and Emerging Trends

“…Tricuspid regurgitation measured as a precursor to pulmonary hypertension was noted in more than 20% of children at a mean age of 6.2 years. 15 The debilitation of recurrent vasoocclusive crises is harder to define precisely for a transplantation threshold, but they significantly impair quality of life. 16 Other severe complications include sickle nephropathy, avascular necrosis, silent stroke with cognitive impairment, priapism, and red cell alloimmunization.…”

Vascular risk assessment in patients with sickle cell disease

“…Longitudinal follow-up of eight patients within this cohort revealed persistent and often increasing elevations in TRV suggesting that, even in early childhood, an abnormal echocardiogram can be a useful indicator of a higher risk population. 36 A correlation with right heart catheterization data, the gold standard diagnostic test for pulmonary hypertension, is not available for children, apart from in case reports. 37 However, the PUSH study demonstrates that an elevated TRV in children is associated with increased hemolytic rate, and oxygen desaturation during a 6-minute walk test.…”