The symptoms associated with Shone’s Complex include lack of appetite, coughing, respiratory infections (e.g. pneumonia), paleness (resulting from anemia), fatigue, water retention, swelling of the extremities, heart murmur, shortness of breath, enlargement of the heart, pulmonary hypertension, and congestive heart failure.
The severity of the symptoms and the prognosis depend largely on how much obstruction of blood flow through the mitral valve into the left ventricle is caused by the supravalvar mitral membrane (SVMM). It is typical of this disease that the obstruction and resulting symptoms will grow worse with the passage of time.
Frequently, coarctation of the aorta is recognized before the other defects are detected. The coarctation may mask the effects of the other lesions and some patients with Shone’s Complex are only diagnosed when symptoms persist after coarctation surgery.