QT dispersion and T wave peak-to-end in pediatric patients with sickle cell disease

The aim of the study was to detect cardiac repolarization changes and the risk of arrhythmias in children with sickle cell disease (SCD) and sickle thalassemia using echocardiography and electrocardiography (ECG).

This is an observational case-control study that compared 20 patients with SCD and 20 patients with sickle thalassemia who regularly follow in the outpatient hematology clinic of Fayoum University Hospital with 40 healthy controls with history of non-hematological or cardiac illness who attended the general outpatient clinic from November 2022 to July 2023. All patients were evaluated clinically and by routine echocardiography, tissue Doppler imaging (TDI), and long-strip ECG.

The QT, QT corrected (QTc), and QT dispersion (QTd) intervals were significantly higher in the case groups (all p = 0.001). There was a significantly higher T-wave peak-to-end interval (Tp-e) among sickle patients in comparison to controls. There was a statistically significant higher level of Tei index and velocity of the e' wave among each case group in comparison to the control group (p < 0.05). As regards QTc and QTd intervals, there was a statistically significant positive correlation with each of estimated pulmonary artery pressure (ESPAP), isovolumetric contraction time (IVCT), Tei index, and velocity of the s' wave among study groups.

The risk of malignant arrhythmia and sudden cardiac death may occur in children with SCD and sickle thalassemia. They had longer QTc, QTd, and Tp-e intervals than healthy individuals. Prolonged QTc was significantly associated with increased left ventricular dimensions, pulmonary hypertension, and global myocardial dysfunction.