Causes & Risk Factors Of Wolff-Parkinson-White Syndrome

Ebstein's Anomaly

Ebstein's anomaly is a congenital heart defect that causes the tricuspid valve, which is located between the right ventricle and right atrium, to malfunction. This anomaly causes the tricuspid to be positioned lower than usual in the right ventricle and for its leaflets to be misshapen, leading to blood leaking back through the valve.

Ebstein's anomaly can also cause heart failure or be responsible for an enlarged heart. While it is not scientifically understood why this defect occurs, it appears in some cases of Wolff-Parkinson-White syndrome as well as in patients with holes in their hearts and those who have arrhythmias. There is some speculation about how pregnant women taking particular medications, such as lithium, could result in the child having Ebstein's.

A Heart Defect

It has been estimated somewhere between seven and twenty percent of patients with Wolff-Parkinson-White syndrome have some other type of heart defect. In fact, roughly fifteen percent of children with Wolff-Parkinson-White syndrome present with another type of congenital heart defect. Scientists are not yet quite sure precisely why this happens, but it is certainly regarded as a risk factor.

One of the most well-documented defects associated with Wolff-Parkinson-White syndrome is familial hypertrophic cardiomyopathy (FHC), which is an autosomal dominant condition that causes ventricular hypertrophy, a thickening of the left ventricle's walls. The reason for this condition is not yet scientifically known.