Blood Flow Obstructions
The heart has two bottom chambers: the left ventricle and the right ventricle. Ventricles pump blood away from the heart. The left ventricle pumps blood out through the aortic valve, to the aorta, and on to the rest of the body. The right ventricle pumps blood out though the pulmonary valve, to the pulmonary artery, and on to the lungs.
Children can be born with an obstruction, or stenosis, in one of the outlet valves from the ventricles. Depending on the location of the obstruction, these are called:
Children can also be born with atresia, or a complete closure or absence of an outlet valve.