Normal and impaired development of the ostium primum type atrial septal defect

: We evaluate 48 patients who had catheterization-proved atrial septal defect ostium primum type. These patients are the 2% of the 2,322 children diagnosed of congenital heart disease by catheterization and angiography in our hospital at the 1971-1988 period. Of 48 children, 36 underwent corrective surgical repair at mean age of 6 years, with a surgical mortality rate of 11.1%. Our mortality rate total was 12.5% and the average follow-up was 9 years. The most recent evaluation in the 32 survivors of complete repair shows that 2 children had complete atrioventricular block and pacemaker implanted, and 26 children had residual mild to moderate mitral regurgitation. Two children are in the functional New York Heart Association class III and 24 children in the class I or II. The estimated actuarial survival rate at the 10-15 years is 86.3% in the total and 88.2% in the operated group.