Cirrhosis as a Moderator of Outcomes in Coronary Artery Bypass Grafting and Off-Pump Coronary Artery Bypass Operations: A 12-Year Population-Based Study

Background Cirrhosis substantially affects morbidity and mortality in patients who undergo complex surgical procedures. However, cirrhosis is not included as a parameter in standardized perioperative cardiac risk assessment models. We sought to identify the impact of cirrhosis on coronary artery bypass grafting (CABG) and off-pump CABG (OPCAB) outcomes. Methods Using the 1998 to 2009 Nationwide Inpatient Sample databases, we identified 3,046,709 patients who underwent CABG procedures, 744,636 (24.4%) of which were OPCAB; 6,448 (0.3%) had cirrhosis. Using hierarchical multivariable regression models, we analyzed the impact of cirrhosis on in-hospital outcomes: mortality, morbidity, length of stay, hospital charges, and disposition. Severity of liver dysfunction was assessed by the Deyo-Charlson comorbidity index. Results In the overall CABG group, cirrhosis was independently associated with increased mortality (adjusted odds ratio [AOR] 6.9, 95% confidence interval [CI] 2.8 to 17), morbidity (AOR 1.6, 95% CI 1.3 to 2.0), length of stay (+1.2 days; p < 0.001), and hospital charges (+$22,491; p < 0.001). The prevalence of cirrhosis in the OPCAB group was 0.3% (n = 2,246); the OPCAB subgroup analysis revealed that the presence of cirrhosis did not affect mortality or morbidity unless there was severe liver dysfunction (mortality AOR 5.1, 95% CI 3.7 to 6.9; morbidity AOR 2.1, 95% CI 1.6 to 2.4). However, in the on-pump CABG patients, cirrhosis was associated with increased mortality and morbidity regardless of the severity of liver dysfunction. Conclusions The impact of cirrhosis on perioperative outcomes and health care costs is significant; CABG should be performed on carefully selected cirrhotic patients and, whenever possible, without the use of cardiopulmonary bypass.