Perioperative Risk Factors for Mortality in Patients Undergoing Surgery for Ebstein's Anomaly at a Single Institution: A Retrospective Analysis

BACKGROUND: Mortality after cardiac surgery for Ebstein's anomaly ranges from 2.5% to 31%. Independent predictors for mortality and morbidity remain poorly defined because of the low incidence of this congenital anomaly. To identify potentially modifiable factors, this retrospective study investigates the prognostic value of perioperative variables for mortality and morbidity. METHODS: We reviewed the charts of 171 patients with Ebstein's anomaly who were at one point in follow-up at our center. Only patients who underwent cardiac surgery for this anomaly were included. The primary endpoint was a composite of mortality or rehospitalization for cardiac reasons within 1 year of surgery. Logistic regression and Cox regression models were used to study the predictive value of various variables. RESULTS: We identified 32 patients (median age 12 years; range 7 days to 70 years) who underwent a total of 49 surgical procedures for Ebstein's anomaly at our institution between November 1987 and March 2015. The following variables were significantly associated with the primary outcome: increased severity of tricuspid valve stenosis (odds ratio 2.089; 95% confidence interval 1.175 to 3.713) and right ventricular dysfunction (1.826; 1.109 to 3.006), partial corrective surgery (versus corrective surgery) (6.709; 1.436 to 31.344), occurrence of major postoperative complications (5.460; 1.419 to 21.008), and increased length of stay in the intensive care unit (1.051; 1.010 to 1.093). A better outcome was observed with the use of intraoperative cardioplegic arrest (0.185; 0.063 to 0.550), atrial septal defect closure during surgery, and longer duration of surgery (0.991; 0.984 to 0.998). CONCLUSION: Several patient-specific characteristics and perioperative characteristics were associated with a poorer outcome after cardiac surgery for Ebstein's anomaly. The outcome seems to be primarily determined by the severity of the valve dysfunction and right ventricular performance, with only a minor role for perioperative surgical or anesthetic technical determinants.status: publishe