Renal Disease is Associated with Poor Outcomes Following Isolated Coronary Artery Bypass Grafting

Abstract

Background: People with renal disease have a markedly higher risk of cardiovascular disease as well as morbidity and mortality after cardiac surgery. Little is known regarding the post-operative adverse outcomes following isolated coronary artery bypass graft (CABG) in the Australian population with renal disease. Objectives: The aim of this study was to examine the effect of different stages of renal disease on patients' risk of post-operative mortality and complications following isolated CABG in an Australian cohort. Methods: Using the ANZSCTS (Australian and New Zealand Society of Cardiac and Thoracic Surgeons) registry, data from 44,968 patients who underwent isolated CABG between 2001 and 2014 were used. The effect of renal disease stages on short-and long-term outcomes were examined using multivariable logistic and Cox's regression methods respectively. Results: Three of 4 Australian patients (74.6%) who underwent isolated CABG had some degree of renal disease: 50.2% mild; 20.9% moderate; 2.1% severe; and 1.6% dialysis-dependent. Adjusted risk of 30-day mortality increased with deteriorating renal disease from mild (1.6-fold) to dialysis-dependent (4.6-fold). Worsening renal disease was also associated with higher risk of post-operative complications. Hazard ratio for long-term survival shows steady increase of mortality risk with worsening renal disease categories from 1.1fold for mild to 3.9-fold for patients on dialysis. Conclusions: Pre-existing renal disease is significantly associated with 30-day and long-term mortality, length of intensive care unit and hospital stay as well as several other post-operative complications.

Future insights of pharmacological prevention for AKI post cardiopulmonary bypass surgery (based on PK/PD approach)

“…In a retrospective study involved 3889 patients, present a correlation between duration use of CPB and incidence of acute kidney injury after cardiac surgery ( Axtell et al, 2020 ), it was part of the intraoperative factors that causes incidence of AKI post-CPB through several mechanisms of action, namely hemodynamic perturbation, mechanical factors, oxygen delivery, carbon dioxide production, and inflammation ( de Somer et al, 2011 ). In addition to those intraoperative factors, there is another condition of preoperative factor that also possible to increase the incidence of AKI post-CPB which commonly caused by the presence of pre-existing kidney disease ( Alramadan et al, 2019 ), pulmonary disease, obesity ( Thakar et al, 2005 ; Fu et al, 2021 ) and older age ( Thakar et al, 2005 ; Chronopoulos et al, 2010 ). Various strategies were made to prevent incidence of AKI related to CPB utilization.…”

Coronary artery bypass grafting: Factors affecting outcomes

“…Systolic dysfunction is represented clinically by decreased ejection fraction (<50%), with or without diastolic dysfunction 28 . The degree of left ventricular dysfunction is a predictor of mortality in patients undergoing coronary artery bypass grafting; with higher mortality and perioperative complications seen in patients with decreasing left ventricular function 28 . Kay et al, 29 investigated the influence of ejection fraction on mortality, morbidity and overall costs on healthcare.…”

“…These include diabetes mellitus, hypertension, hyperlipidaemia, and peripheral vascular disease 34 . The severity of renal disease is an independent risk factor for adverse outcomes to coronary artery bypass grafting surgery 28,35 . The adverse outcomes studied were for increased mortality, bleeding risks, prolonged intensive care unit (ICU) stay, cerebrovascular accidents, and repeat revascularization.…”

“…28 The degree of left ventricular dysfunction is a predictor of mortality in patients undergoing coronary artery bypass grafting; with higher mortality and perioperative complications seen in patients with decreasing left ventricular function. 28 Kay et al, 29 investigated the influence of ejection fraction on mortality, morbidity and overall costs on healthcare. They analyzed 1,354 patients undergoing isolated CABG and noted five times increase in all-cause hospital mortality in patients with an ejection fraction (EF) <30% compared to those with EF ≥≥ 40% (p < .001).…”

“…Left ventricular dysfunction can be further classified as systolic or diastolic. Systolic dysfunction is represented clinically by decreased ejection fraction (<50%), with or without diastolic dysfunction 28 . The degree of left ventricular dysfunction is a predictor of mortality in patients undergoing coronary artery bypass grafting; with higher mortality and perioperative complications seen in patients with decreasing left ventricular function 28 .…”