Heart Function Disorders In Sickle Cell Disease

Sickle cell disease (SCD) is a hereditary anemia characterized by chronic hemolytic anemia and vaso-occlusive episodes, associated with a high susceptibility for infections and damage to all vital organs. Cardiologic effects of SCD are dilatation and hypertrophy of the left ventricle and pulmonary hypertension. The prevalence of these cardiac complications in children with SCD living in the Netherlands is unknown. The role of hemolysis in this process is still unclear. Therefore, the objectives of this study are: 1) to evaluate the prevalence of cardiac abnormalities in children with SCD living in the Netherlands, 2) to analyse the association between cardiac abnormalities and the severity of anemia and hemolysis.

Cross-sectional study, including 92 children with SCD (genotype HBSS, HBSC or HBS-beta 0) treated at the Emma Children's Hospital AMC. None of the children had cardiac abnormalities unrelated to SCD. Echocardiograms and electrocardiograms were performed in a stable state. All cardiac values were corrected for BSA. Echocardiographic values 20% above or under the average of an age matched control group were considered abnormal. Laboratory hematological parameters were obtained within one year of the cardiac imaging. All statistical analyses were performed with SPSS 18 software, using Pearson correlations and T-tests. Forced-entry multivariate regression analysis was conducted with hematological parameters, age and SCD genotype as independent variables and cardiologic parameters as dependent variables.

The study group had a mean age of 13 years (SD 5,5) and contained 49 boys (53,3%). All children had a normal shortening fraction. Almost half of the children (39%) had a dilated left ventricular internal diameter in diastole and systole. Dilatation was inversely correlated with the Hb level. When analysed with multivariate analysis, both Hb and bilirubin were independently associated with left ventricular dilatation, suggesting that hemolysis deteriorates cardiac structure by a mechanism separate from the effect of anemia. There was no association between the left ventricular dilatation and age.

Pediatric sickle cell patients have significant dilatation of the left ventricle, an abnormality that is significantly and independently associated with the severity of anemia and bilirubin levels, but in spite retain a normal shortening fraction.

No relevant conflicts of interest to declare.