Outcome of the unoperated adult who presents with congenitally corrected transposition of the great arteries.

Objectives: The goal of this study was to determine the presentation and outcome of the unoperated adult with congenitally corrected transposition of the great arteries.
Background: The presentation of this disorder and the outcome in unoperated adults have not been well defined.
Methods: All unoperated patients > or =18 years old were evaluated for spectrum of disease, hemodynamic severity, timeliness of diagnosis and referral, and outcome.
Results: Forty-four patients aged 20 to 79 years (mean, 44) were followed up to 144 months. In 29 (66%), the correct diagnosis was first made at age > or =18 years; the diagnosis was missed in seven of these patients in a prior cardiology consultation, despite cardiac imaging. Systemic atrioventricular valve (SAVV) regurgitation (grade > or =3/4) was noted in 26 patients (59%). Thirty (68%) had surgical intervention, including SAVV replacement in all, with no early mortality. Preoperatively, this subset had significant dysfunction of the systemic ventricle (SV) (ejection fraction [EF], 40 +/- 10%), and most had advanced symptoms (25 with ability index > or =2/4). In 16 (53%), SAVV regurgitation > or =3/4 and ventricular dysfunction had been documented for >6 months. The mean EF of the SV decreased significantly postoperatively (34 +/- 11%, p = 0.006). Four patients (13%) eventually required cardiac transplantation. Poor preoperative EF of the SV predicted eventual need for transplantation (p = 0.001).
Conclusions: Patients with unoperated congenitally corrected transposition of the great arteries are often misdiagnosed in adulthood and are referred late despite symptomatic SAVV regurgitation and significant SV dysfunction. Although excellent early surgical results can be achieved, significant residual dysfunction of the SV is common.