Liver dysfunction as an important predicting risk factor in patients undergoing cardiac surgery: a systematic review and meta-analysis.

Liver function is not considered as a risk factor by current risk scores, such as EUROSCORE II or STS-Score for cardiac surgery. The aim of this study was to review the role of liver dysfunction, classified by the Child-Turcotte-Pugh classification or model for end-stage liver disease scores, as a risk factor for mortality and morbidity of patients following cardiac surgery. The Pubmed referencing library was searched. The rates of mortality and morbidity were calculated using SPSS software. The mortality rates in patients of Child class A, Child class B, and Child class C were pairwise compared respectively. A total of 22 reports including 939 patients from eight countries were reviewed. The mortality rate of patients increased in accordance with increased CTP classification. The lowest mortality rate was recorded in Child class A patients, followed by Child class B patients and the highest mortality rate was observed in Child class C patients. The mean complication rate ranged from 3.82% to 22.15%. Child class C patients should be considered unacceptable for cardiovascular surgery. As two studies revealed, patients with a higher MELD score had significantly higher mortality rates. Liver function should be viewed as an important risk factor for cardiovascular surgery, based on its strong association with mortality and morbidity.