OBJECTIVE To determine the frequency and type of cardiac manifestations in children with systemic lupus erythematosus (SLE) and investigate whether cardiac involvement of SLE in children was associated with any autoantibody pattern. METHODS Retrospective analysis of the medical records of all children with SLE (31 patients) seen between January 1984 and January 1994 by the paediatric rheumatology service at Children's Hospital in New Orleans. All patients satisfied the American College of Rheumatology criteria for the diagnosis of SLE. Paediatric SLE patients with cardiac manifestations based on echocardiogram were identified. Autoantibody tests at diagnosis were identified retrospectively by chart review, and the correlation between autoantibodies and cardiac involvement was analysed using the two tailed Fisher's exact test. RESULTS Thirteen (42%) of 31 SLE patients had cardiac manifestations of SLE. Seven (22%) had pericarditis without myocarditis, five (16%) had pericarditis and myocarditis, and one (3%) had myocarditis without pericarditis. Two patients (6%) with pericarditis had cardiac tamponade. Cardiac manifestations of SLE usually occurred at the time of diagnosis or within six months. Anti-Ro/SS-A antibodies were present in serum samples of nine of 11 (82%) patients with cardiac involvement and in five of 15 (33%) without cardiac involvement (p = 0.02). Anti-La/SS-B antibodies were present in serum samples of six of 10 (60%) patients with cardiac involvement and two of 15 (13%) without cardiac involvement (p = 0.03). Anti-Sm and anti-RNP antibodies showed no correlation with the presence of cardiac disease. CONCLUSIONS Cardiac involvement in our paediatric SLE population was frequently found and correlated significantly with the presence of anti-Ro/SS-A and anti-La/SS-B antibodies.