Waterston anastomosis. Comparison of results of operation berfore and after age 6 months.

The results of 40 Waterston aortico-to-pulmonary anastomoses are reviewed from the experience at The Hospital for Sick Children, Toronto, between June 1966 and October 1969. Over the age of 6 months there was one death associated with the procedure in 12 cases. Under the age of 6 months the mortality associated with the operation in cases of tetralogy of Fallot was 50%. This represents the severer degree of defect as well as the increased technical difficulties in the younger age group.