Adult patients with congenital heart disease are presenting more frequently for cardiac surgery. Frequently, pediatric congenital heart surgeons perform these procedures at pediatric hospitals. Between July 1995 and June 2000, a retrospective review of adult patients (> or = 18 years old) who had undergone cardiothoracic operations was performed. A total of 112 operations were performed and divided into two groups--81 cardiac operations in 79 patients and 31 noncardiac operations in 23 patients. One patient had a cardiac and noncardiac operation performed. The overall early operative mortality was 6% (6/101). There were 3 late deaths. New-onset cardiac arrhythmias requiring treatment were diagnosed after 5/81 (6%) cardiac operations. Six of 79 (7%) patients were diagnosed with postoperative clinical depression. An acceptable mortality can be achieved when adult patients undergo cardiothoracic operations at a pediatric facility. New-onset arrhythmias necessitating treatment are relatively common, and postoperative clinical depression should be anticipated.