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In this anomaly, the left coronary artery usually arises from the main pulmonary artery, usually resulting in left, ventricular and septal ischemia and development of extensive collaterals between the right and left coronary arteries. Surgical repair is performed at any age immediately following the establishment of the diagnosis. Early repair is performed to avoid congestive heart failure and myocardial fibrosis caused by inadequate myocardial perfusion accentuated by a phenomenon with retrograde flow from the left coronary into the main pulmonary artery. Surgery should always establish a two-coronary system.

Total repair is carried out soon after establishing the diagnosis and medical stabilization of the patient. The procedure can be emergent shortly after birth when there is obstruction of the common pulmonary venous channel (as with a subdiaphragmatic connection), or in the early days of life when there is obstruction at the atrial septal level (supracardiac or intracardiac connection). When there is no obstruction to pulmonary venous return, surgery is required in the early weeks of life because the large left-to-right shunt causes congestive heart failure or failure to thrive with or without pulmonary artery hypertension.

In the presence of this rare anomaly, a membrane separates the left atrium into two chambers. The proximal chamber communicates with the pulmonary veins, while the distal chamber communicates with the atrial appendage and mitral valve.

Babies born with these anomalies have a deficiency of the atrial septum, ventricular septum, and/or abnormalities of the atrio-ventricular (AV) valves. In partial AV canal defect, there is absence of the septum primum and usually a cleft in the anterior mitral leaflet. This anomaly is synonymous with primum atrial septal defect. The intermediate form of AV canal encompasses a primum atrial septal defect, ventricular septal defect usually in the inlet position, and usually a cleft mitral valve. The annulus between tricuspid and mitral valves is intact. In complete AV canal, the primum atrial septal defect is in continuity with a high ventricular septal defect because there is no annular continuity of mitral and tricuspid valves. This results in a single intracardiac AV valve that functions as both mitral and tricuspid valves. All patients have a significant left-to-right intracardiac shunt and in the presence of complete AV canal there is always severe pulmonary hypertension with or without AV valve regurgitation. Early surgery is necessary because of congestive heart failure and, in the presence of pulmonary artery hypertension, to avoid early development of pulmonary vascular obstructive disease.

Arterial switch repair is the preferred operation for d-transposition of the great arteries without severe anatomic left ventricular outflow tract narrowing or when such narrowing can be treated with resection. Other surgical repairs are rearely performed. The traditional contraindication to its use is the presence of an abnormal pulmonary valve, which would become the aortic valve after repair, although today one would consider combining a form of the Ross procedure and arterial switch operations for management of such a patient. Unusual coronary artery anatomy or intramural course of a coronary are not contraindications. Arterial switch is usually performed in the first week of life because the preparation of the left ventricle may be unpredictable after 10 to 14 days of age. If the operation is delayed, staged repair may be performed with preparatory temporary pulmonary artery banding and Blalock shunt followed by arterial switch after adequate left ventricular hypertrophy has developed.

Although the circulation is normal in this anomaly, surgical repair of associated lesions may be necessary. Ventricular septal defect (VSD) and/or pulmonary stenosis is common, and technical aspects of repair of these problems are unusual because of differences in ventricular morphology. The double-switch operation is also gaining popularity in order to place the morphologic left ventricle in the systemic circulation, and the morphologic right ventricle in the pulmonary ciruclation.

Because of the direct aorta to pulmonary artery connection in this anomaly, pulmonary artery hypertension and excessive pulmonary blood flow are present from birth, necessitating total corrective surgery immediately after establishing the diagnosis and preferably in the first month of life.

In this anomaly, the left coronary artery usually arises from the main pulmonary artery, usually resulting in left, ventricular and septal ischemia and development of extensive collaterals between the right and left coronary arteries. Surgical repair is performed at any age immediately following the establishment of the diagnosis. Early repair is performed to avoid congestive heart failure and myocardial fibrosis caused by inadequate myocardial perfusion accentuated by a phenomenon with retrograde flow from the left coronary into the main pulmonary artery. Surgery should always establish a two-coronary system.

Survival in infants with this interrupted aortic arch depends on ductal patency for lower torso perfusion, so prostaglandin-E (PGE) infusion is always used during medical stabilization followed by immediate surgical repair. Repair of Type A interruption (interruption beyond the left subclavian artery) is performed through a left throacotomy. Associated anomalies [e.g., ventricular septal defect (VSD)] may be palliated with pulmonary artery banding through the same thoracotomy or repaired primarily working through a separate median sternotomy. Type B (interruption beyond left carotid artery) or Type C (interruption between innominate and left common carotid arteries) interruption and associated anomalies are repaired through a median sternotomy with cardiopulmonary bypass, deep hypothermia, and temporary low-flow cerebral perfusion.

There are many techniques to repair aortic coarctation, and each has advantages and disadvantages in accomplishing relief of the aortic obstruction with the lowest mortality and chance of recurrence. No single technique is superior for use in all patients.