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Prolonged QTc interval in children and young adults with sickle cell disease at steady state

Robert I Liem1, Luciana T Young, Alexis A Thompson

  • 1Division of Hematology, Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA. rliem@childrensmemorial.org

Pediatric Blood & Cancer
|February 21, 2009
PubMed

Insights

QTc prolongation is common in sickle cell disease (SCD), affecting 38% of patients. This finding is linked to elevated pulmonary pressures, hemolysis, and acute chest syndrome, not left ventricular hypertrophy.

Area of Science:

  • Cardiology
  • Hematology
  • Pediatrics

Background:

  • QTc prolongation may be more prevalent in sickle cell disease (SCD) than previously recognized.
  • The clinical associations and natural history of QTc prolongation in SCD patients are not well understood.
  • This study aimed to determine the prevalence of prolonged QTc and its clinical correlates in young individuals with SCD.

Purpose of the Study:

  • To establish the prevalence of QTc prolongation in children and young adults with sickle cell disease.
  • To investigate the relationship between QTc prolongation and various clinical factors in this population.

Main Methods:

  • Analysis of data from 76 SCD patients aged 10-25 years.
  • Screening included echocardiography (ECHO), 12-lead electrocardiogram (ECG), and laboratory tests.
  • Prolonged QTc was defined as an interval >440 msec.

Main Results:

  • A significant prevalence of QTc prolongation was observed in 38% (29/76) of subjects.
  • Subjects with prolonged QTc showed higher mean tricuspid regurgitant jet velocity, lactate dehydrogenase, and aspartate aminotransferase levels.
  • A history of recurrent acute chest syndrome was more frequent in subjects with prolonged QTc.

Conclusions:

  • QTc prolongation is a frequent finding in sickle cell disease, independent of left ventricular hypertrophy.
  • Elevated pulmonary pressures, hemolysis, and acute chest syndrome are potential risk factors for QTc prolongation in SCD patients.
Abstract

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