The early results of treatment of simple transposition in the current era.

A total of 187 neonates with simple transposition of the great arteries (TGA) have been entered into a twenty institution cooperative study between Jan. 1, 1985, and June 1, 1986. Eighty-two percent entered within the first 2 days of life. Seventy-six of the 187 patients were initially entered into a treatment protocol leading to an arterial switch repair, 45 into one leading to an atrial switch (Mustard) repair, and 49 into one leading to a Senning repair. Five (7%) of the patients entered initially into an arterial switch protocol later were crossed over to an atrial switch protocol, and 7% of those entered into an atrial switch (Mustard) protocol were crossed over to an arterial switch protocol. Formal follow-up information is available on all patients. Only 5% of patients entered into an arterial switch protocol were without repair 2 weeks after entry, whereas 96% and 100%, respectively, of those entered into a Mustard or Senning atrial switch protocol were without repair at that time. Ninety-seven percent of the first group had no preliminary procedures other than balloon atrial septostomy, which was true of only 76% and 90%, respectively, of the last two groups. No deaths before repair occurred in the first group, whereas five occurred in the latter two groups (P = 0.06). Overall survival rate among the 187 patients was 81% at 1 year. The only risk factors for death were birth weight, date of entry into the study, and an arterial switch protocol in the group of institutions at high risk for arterial switch repair; neither an arterial nor an atrial switch protocol was a risk factor per se. According to the multivariate equation, the 12-month predicted survival rate of a patient with a birth weight of 3.4 kg, entered currently into atrial or arterial switch protocols (except in the high risk for arterial switch group of institutions) is 92%.