Left heart hypoplasia evolving up to 21 years, after total cavopulmonary operation performed at 5 years of age

Hypoplasia of the left heart is characterized by very small dimensions of the left cardiac cavities, represented by the left atrium, mitral valve, left ventricle, aortic ring and ascending aorta. Systemic circulation thus becomes dependent on the ductus arteriosus with reverse flow from the hypertensive pulmonary artery to the descending aorta, and also to the ascending aorta. Coronary circulation is also dependent on this reverse flow, which is why there is a high chance of myocardial infarction, even in the first days of life. It is easy to imagine that, on decreased pulmonary arterial pressure or ductus arteriosus caliber, there is an unfavorable evolution towards low cardiac output. The right heart is enlarged and atrial septal defect invariably accompanies this defect. When this atrial defect appears to be of reduced dimensions, known as restrictive, it causes retrograde pulmonary hypertension. On the other hand, when larger, it may favor the faster involution of pulmonary hypertension, with congestive symptoms and low output. In the rare cases of intact atrial septum, anomalous pulmonary vein drainage remains in order of maintenance and viability of circulation. Left heart hypoplasia is the fourth most common heart disease in the neonatal period, with high mortality, even in this period, and corresponds to 1.5% of all congenital heart diseases. (author)