Preoperative predictability of right ventricular failure following surgery for Ebstein's anomaly

Postoperative right ventricular (RV) failure is a severe complication after tricuspid valve (TV) surgery in patients with Ebstein s anomaly. We investigated the preoperative predictability of postoperative mortality and morbidity by assessing the influence of age, RV size and RV function on in-hospital mortality and on the clinical course during the intensive care unit (ICU) stay. METHODS: We retrospectively analysed 189 patients who had undergone TV surgery for Ebstein s anomaly at our centre. For this study, only patients with preoperative cardiac magnetic resonance imaging (MRI) scans, who were operated on from 2005 to May 2018, were included. Three potential risk factors were proposed: (i) RV end-diastolic volume index 200ml/m2, (ii) RV ejection fraction (EF) 40% and (iii) age at operation 50years. Primary end points were death or the need for extracorporeal membrane oxygenation. Secondary end points were postoperative inotropic therapy, ventilation time, renal failure and duration of ICU stay and hospital stay. RESULTS: A total of 70 patients with preoperative cardiac MRI scans were included: 57 had undergone TV repair and 13 TV replacement. Thirty patients exhibited none of the defined risk factors, 24 patients exhibited 1 risk factor, 13 patients exhibited 2 risk factors and 3 patients exhibited 3 risk factors. There were 4 in-hospital deaths (6%): 3 of these patients had 3 risk factors, and 1 patient had 2 risk factors. In patients with 1 or more risk factors, the odds ratio for primary end point was 2.5 (P=0.43) and in patients with 2 or more risk factors, the odds ratio was 18.5 (P=0.001). Patients with at least 1 risk factor required prolonged inotropic drug administration and required a longer hospital stay (median 20days vs 14days, P=0.029). Patients with at least 2 risk factors showed a significantly prolonged ventilation time (median 10h vs 6h, P=0.001). Time in the ICU was longer in patients with 2 or more risk factors (median 9days vs 4.5 days, P=0.003). CONCLUSIONS: RV end-diastolic volume index 200ml/m2, RV-EF 40% and age 50years are helpful factors to identify patients with an increased perioperative risk. The results also suggest that earlier surgery may yield more favourable results in patients with Ebstein s anomaly..