The most commonly recommended age for correction of a tetralogy of Fallot (TOF) is:
However, systemic-to-pulmonary shunts, generally a B-T shunt, may still be preferred with an unstable neonate younger than 3 months, when an extracardiac conduit is required because of an anomalous left anterior descending coronary artery, or when pulmonary atresia, significant branch pulmonary artery hypoplasia, or severe noncardiac anomalies coexist with TOF.
Which of the following is the most common type of ventricular septal defect (VSD) to require surgical correction?
Perimembranous ventricular septal defects (VSDs) are the most common type requiring surgical intervention, comprising approximately 80% of cases. These defects involve the membranous septum and include the malalignment defects seen in TOF.
What is the best predictor of spontaneous closure of a VSD?
VSDs may dose or narrow spontaneously, and the probability of closure is inversely related to the age at which the defect is observed. Thus, infants at 1 month of age have an 80% incidence of spontaneous closure, whereas a child at 12 months of age has only a 25% chance of closure. This has an important impact on operative decision making, because a small or moderate-size VSD may be observed for a period of time in the absence of symptoms. Large defects and those in severely symptomatic neonates should be repaired during infancy to relieve symptoms because irreversible changes in pulmonary vascular resistance may develop during the first year of life.
Which of the following cardiac abnormalities, all of them well-tolerated during fetal life, becomes a serious problem at birth?
In fetal life, blood reaching the right atrium has been oxygenated by the placenta. This blood bypasses the high-resistance pulmonary circulation to enter the systemic circulation through septal defects and the ductus arteriosus. When the child is born, the pulmonary circulation becomes important. Septal defects and the ductus arteriosus can be tolerated by the newborn child, but tricuspid atresia, pulmonic valve stenosis, or other right ventricular outflow obstruction forces a right-to-left shunt, with development of cyanotic heart disease.
Cor triatriatum is:
Cor triatriatum results in obstruction of pulmonary venous return to the left atrium with a diaphragm dividing the chamber receiving pulmonary return from the camber in continuity with the mitral valve and LV. The degree of obstruction is variable and depends on the size of fenestrations present in the left atrial membrane, the size of the ASD, and the existence of other associated anomalies. If the communication between the superior and inferior chambers is less than 3 mm, patients are symptomatic during the first year of life. The afflicted infant will present with the stigmata oflow cardiac output and pulmonary venous hypertension, as well as congestive heart failure and poor feeding.
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