Myocardial dysfunction after cardiopulmonary bypass (CPB) is a significant cause of morbidity and mortality after congenital cardiac surgery. The aim of this study was to evaluate myocardial function on sevoflurane anesthesia after CPB during ventricular septal defect repair.

Forty patients were randomly allocated into two groups: sevoflurane-fentanyl was used in group S, midazolam-fentanyl in group M. Myocardial performance index (MPI) and ejection fraction (EF) were measured by transesophageal echocardiography before incision and after operation. Serum cardiac Troponin-I (cTnI) levels were measured before incision, and at 0, 12, and 24 h after operation.

MPI increased after operation in both groups (S: 0.35 ± 0.06 vs. 0.43 ± 0.05, M: 0.36 ± 0.07 vs. 0.46 ± 0.06 [P < 0.05]), but there was no significant difference between groups. EF decreased after operation in both groups (S: 65.1 ± 5.5% vs. 62.7 ± 3.9%, M: 64.9 ± 5.3% vs. 61.4 ± 4.4% ([P < 0.05]), but there was no significant difference between groups. cTnI was markedly elevated after operation, and decreased thereafter. There was no significant difference between groups.

Both groups showed decreased myocardial function after CPB, but there were no difference between groups. Sevoflurane did not adversely affect intraoperative myocardial function compared to midazolam.