Children with sickle cell disease who also have lower blood oxygen levels while both asleep and awake are likely to have heart abnormalities, researchers at Washington University School of Medicine in St. Louis and other institutions have found.
Heart problems are fairly common in young adults with sickle cell disease, but physicians don't fully understand why. The researchers demonstrated that lower oxygen saturation in the blood was linked to the heart structure seen in the 44 children studied.
Sickle cell disease is an inherited blood disorder affecting red blood cells, which contain hemoglobin, the substance that carries oxygen from the lungs to all parts of the body. In patients with this disease, red blood cells contain an abnormal type of hemoglobin that causes the normally round, flexible red blood cells to become stiff and sickle- or crescent-shaped. The sickle cells can't pass through tiny blood vessels, which can prevent blood from reaching some tissues and can result in tissue and organ damage, pain and stroke.
In addition, sickle cells are short lived and lead to a shortage of red blood cells and anemia, which make the heart grow bigger because it has to work harder, says Mark C. Johnson, MD, associate professor of pediatrics at Washington University School of Medicine and first author of the study.
In this study, the first to analyze sleep studies and echocardiograms of children with sickle cell disease, these heart abnormalities were found in the left pumping chamber, or left ventricle, of the children's hearts. The findings included an enlarged left ventricle, called ventricular hypertrophy, and abnormal blood filling of the left ventricle, called diastolic dysfunction. Both are associated with early death in adults with sickle cell disease, but the meanings of the same results in children are unclear.
"This suggests that the beginning of adult heart disease may start in children, but we need to follo
|Contact: Beth Miller|
Washington University School of Medicine