Objective: There is ample evidence that premature and low birth weight children have a poor outcome after congenital heart surgery. The aim of the present study was to characterize the perioperative factors which significantly influence the outcome of these babies following cardiac surgery, and to clarify whether the RACHS-1 and the Aristotle score are compatible for this complex kind of heart surgery.
Methods: During the past 10 years, 108 children with a body weight of less than 3000 g were operated, including 43 premature babies. Mean weight at operation was 2.5 +/- 0.5 kg, mean age was 36.8 +/- 55 days. Fifty percent of the treatments were categorized into risk groups 4 and 6 and 54 % belonged to the complexity levels 3 and 4. Eighty-one operations (75 %) were performed using extracorporeal circulation.
Results: The 30 day mortality rate was 18 %, and the overall mortality rate was 30 %. The correlation between mortality rates and risk groups was significant ( p < 0.001). Other significant factors were preoperative acidosis ( p = 0.026), preoperative catecholamine support ( p < 0.001), prolonged ICU stay (> 7 days) after operation ( p < 0.001), and postoperative infection ( p = 0.019). In addition, X-clamp time ( p = 0.029) and palliative procedures ( p < 0.001) were significant factors for poor outcome.
Conclusion: The results demonstrate that the mortality for correction of congenital heart defects in children weighing less than 3000 g depends on several factors. The risk groups of the RACHS-1 study and the complexity levels of the Aristotle score are useful tools to assess preoperative risk.