Objectives: Preoperative liver dysfunction is a well-known risk factor for adverse events after major surgery. However, there is only little data regarding the precise role of the Model of End-Stage Liver Disease (MELD) score and the De Ritis ratio (DRR, alanine transaminase/aspartate aminotransferase) as a predictor for outcome after left ventricular assist device (LVAD) implantation.
Methods: A retrospective analysis of all patients undergoing LVAD implantation at our institution between January 2012 and August 2014 was performed. The primary outcome was survival at 180 days after surgery.
Results: During the observation period, 63 patients underwent LVAD implantation (mean age 59.9 ± 8.3 years, 50% male). Mean preoperative ejection fraction was 16.3 ± 7.7, 13 patients required preoperative renal replacement therapy and 9 patients were on extracorporeal life support. Mean Interagency Registry for Mechanically Assisted Circulatory Support level was 2.8 ± 1.3, mean preoperative MELD was 12.7 ± 7.2, mean preoperative DRR was 2.01 ± 4.4. Aspartate aminotransferase (102 ± 220.8 vs 57.8 ± 123.4 U/l, P = 0.041), MELD score (16.1 ± 8.8 vs 11.4 ± 6.1, P = 0.017) and DRR (4.2 ± 7.8 vs 1.1 ± 1.1, P = 0.001) were significantly higher in non-survivors than in survivors after 180 days. Using logistic regression analyses, a DRR >1.37 was an independent predictor for 30-day mortality [odds ratio (OR) 4.5] and 180-day mortality (OR 4.1). In addition, the DRR was associated with postoperative acute kidney injury with need for renal replacement therapy (OR 4.2) and prolonged postoperative ventilation time >72 h (OR 3.8). Using receiver operator characteristics analyses, DRR showed a sensitivity of 0.80 and a specificity of 0.81 (area under the curve 0.834, cut-off 1.37) for 180-day mortality.
Conclusions: The DRR is predictive of early and mid-term mortality as well as relevant morbidities in patients undergoing LVAD implantation. Therefore, the DRR should be considered within the preoperative risk stratification and patient selection for LVAD implantation.
Keywords: Alanine transaminase; Aspartate aminotransferase; DeRitis ratio; Left ventricular assist device; Liver dysfunction; MELD.
© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.