Figure 4.

 Top: Model published in 1985 contrasting estimates of the survival curves for the normal population with patients committed to a Senning operation at age 1 month with a 2% operative mortality and an annual late hazard of 2% and for patients committed to a switch operation at birth with a 40% early mortality and a 0.3% annual late hazard. Bottom: Current model, with normal survival as above. The Senning operation is assumed to take place at age 4 months and be associated with a hazard of 16% (including preoperative deaths) and an annual late hazard of 0.7%. The switch is assumed to be done at age 2 weeks and be associated with a 6.2% mortality (including preoperative deaths) and a 0.16% annual late hazard