Hypoplastic left heart syndrome is a condition where the left side of the heart is unable to do its normal work of pumping blood trough the body. One of the common features of HLHS is that the outlet valve from the left ventricle (the aortic valve) and the area just beneath (the left ventricular outflow tract) are very poorly developed and simply too small to work. There have been previous studied which have shown a clustering of problems with the aortic valve in relatives of children with HLHS. Despite this information, systematic screening of relatives of people with HLHS is not universally undertaken
Recent evidence has emerged that the incidence of cardiovascular malformations in first degree relatives (mother, father or siblings) of children with HLHS is relatively high. The key facts are:
- 11% of first degree relatives had a cardiovascular malformation and these included not only aortic valve problems but also dilatation of the ascending aorta, coarctation of the aorta and problems in the development of blood venous return from the lung.
- One in 3 families had at least another member of the family with a cardiovascular malformation.
- Most of the cardiovascular malformations (66% or 2 in 3) were previously undiagnosed.
- 13% of siblings had a cardiovascular malformation.
These results support the practice of routine family screening by a cardiologist of siblings and parents of children with HLHS.