Cardiac catheterization in infants weighing less than 1,500 grams

Background: The improved survival of very low-birth-weight (<1,500 g) infants justifies more aggressive attempts to treat underlying congenital heart disease than in the past. Methods: We retrospectively reviewed all catheterizations performed at our institution between January 1, 1990 and June 1, 2004 in infants weighing <1,500 g. We performed a 3:1 case-control study. Comparisons were randomly selected from a group of patients catheterized within 6 months of the cases and weighing 2-3 kg. All catheterization data, angiograms, and hospital charts were reviewed. Results: Eighteen patients weighing <1,500 g underwent catheterization. Fifty-four patients were selected as comparisons. There were no significant differences in the age at catheterization, procedure time, fluoroscopy time, or contrast amount (cc/kg). The lower-birthweight infants were more likely to be premature (median age 29 vs. 37 weeks, P < 0.001), and to have left-sided obstructive lesions including aortic stenosis or coarctation. The comparison patients were more likely to be postoperative (28% vs. 0%, P = 0.02), and included a higher number with hypoplastic left heart syndrome. There was an increased incidence of interventions performed in the lower-birth-weight infants (83% vs. 41%, P = 0.002). There was a difference in the interventions performed between the two groups: the comparisons had more atrial septal procedures, and the lower-birth-weight infants had more coarctation dilations and aortic valve dilations. There were no significant differences in the acute success rate of the procedures (100% vs. 95%), overall complication rate (56 vs. 57%), incidence of blood transfusions (44 vs. 30%), or major complications (11 vs. 13%) between the lower-birth-weight and comparison groups respectively. There was a trend towards higher survival rate in the comparison group in this small study population, but it did not reach significance (80 vs. 61%, P = 0.13). Conclusions: Cardiac catheterization in neonates <1,500 g is more likely to include percutaneous intervention, especially on the left side, but is generally successful with a complication rate similar to procedures performed in larger infants. Although these procedures are rare, improved miniaturization of equipment would facilitate safer interventions.