Before the 1980’s, most children with significant congenital heart defects were treated with palliation only. Since then, advances in diagnosis, treatment and perioperative management have radically changed the outcome of this constellation of disease. Major advances include the development of prostaglandin E1 designed to keep the ductus arteriosus open, bedside diagnosis by echocardiogram, improved techniques in cardiopulmonary bypass, the development of interventional catheterization and improved perioperative management.

Roughly 25% of those with congenital heart disease will need intervention in the neonatal period. Conditions that are more serious and more prone to require early intervention include critical aortic stenosis, critical pulmonary stenosis, interruption of the aortic arch, transposition of the great arteries, truncus arteriosus, total anomalous pulmonary venous return, and hypoplastic left heart syndrome .

Preoperative mortality is difficult to assess secondary to the paucity of literature available on the subject. Preoperatively, major complications include acidosis and cyanosis due to circulation deficits. Management of these conditions have improved. However, the decline in preoperative mortality is most likely due to other factors. Advances in diagnosis, including prenatal and perinatal ultrasonography have lead to earlier intervention. This is most likely the major factor in the decline of preoperative mortality as permanent damage to the systemic or pulmonary circulation is averted.

Several studies have found that the greatest mortality risk occurs in the thirty days following surgery. Mortality rates for this period has also decreased significantly, with many anomalies associated with less than five percent mortality. Truncus arteriosus was first repaired in 1968. A study from 1993 showed the mortality rate for this condition to be 11-17%. A recent study from the same group showed the mortality to be 4%, a wonderful improvement .

For transposition of the great arteries , the survival rates range from 93-97% in two recent studies. Those with low birth weights have been shown to have reduced perioperative survival. In most cases, the risk of delaying intervention outweighs the risk of surgery, and the defect is repaired.

There are several noncardiac complications that occasionally occur in the perioperative period. The first is necrotizing enterocolitis , which has a frequency of roughly 3.3% after repair of a congenital heart defect. The frequency in the general population is 0.3-3 per 1,000 newborns. Another complication is transient kidney failure , with a frequency of 5% in the perioperative period. This is thought to be associated with bypass effects and the potential for hypotension (low blood pressures) or inadequate perfusion of bodily organs during cardiopulmonary bypass.

Late outcomes in children with congenital heart disease are difficult to assess for the recent period as long-term study results are not available yet. Most patients who survive the perioperative period have an excellent chance of survival. There is, however a significant increase in neurodevelopmental complications in these children. One study compared the effects of deep hypothermic circulatory arrest versus deep hypothermic low flow cardiopulmonary bypass . The study found that those undergoing circulatory arrest had an increased incidence of postoperative seizures, a decrease in psychomotor developmental scores at one year, and an increase in gross and fine motor abnormalities in childhood. 68% of children in this study had definite or possible abnormal neurodevelopment, most of which was classified as mild. As such, our current methods of body organ protection during cardiopulmonary bypass and circulatory arrest need to be constantly reevaluated, updated and improved in order to reduce these developmental disorders. There is good news however, as most major centers performing a large volume of congenital heart surgery are involved in research efforts to improve techniques of cardiopulmonary bypass and protection of the central nervous system during hypothermic circulatory arrest.

Overall, survival in the preoperative and perioperative period after congenital heart surgery have improved. Improvements in early postoperative outcomes and long-term outcomes is related to advances in diagnosis and treatment. It is logical to postulate that this trend will continue as technology and treatments continue to advance.

Reference:
Outcome of Neonates with Congenital Heart DIsease, diagnosisheart.com

McElhinney DB, Wernovsky G; Outcomes of neonates with congenital heart disease. Current Opinions in Pediatrics 2001, 13:104-110.