Effect of Perioperative Lipid Status on Clinical Outcomes after Cardiac Surgery

Abstract

Patients undergoing cardiac surgery are at increased cardiovascular risk, which includes altered lipid status. However, data on the effect of cardiac surgery and cardiopulmonary bypass (CPB) on plasma levels of key lipids are scarce. We investigated potential effects of CPB on plasma lipid levels and associations with early postoperative clinical outcomes. This is a prospective bio-bank study of patients undergoing elective cardiac surgery at our center January to December 2019. The follow-up period was 1 year after surgery. Blood sampling was performed before induction of general anesthesia, upon weaning from cardiopulmonary bypass (CPB), and on the first day after surgery. Clinical end points included the incidence of postoperative stroke, myocardial infarction, and death of any cause at 30 days after surgery as well as 1-year all-cause mortality. A total of 192 cardiac surgery patients (75% male, median age 67.0 years (interquartile range 60.0–73.0), median BMI 26.1 kg/m2 (23.7–30.4)) were included. A significant intraoperative decrease in plasma levels compared with preoperative levels (all p < 0.0001) was observed for total cholesterol (TC) (Cliff’s delta d: 0.75 (0.68–0.82; 95% CI)), LDL-Cholesterol (LDL-C) (d: 0.66 (0.57–0.73)) and HDL-Cholesterol (HDL-C) (d: 0.72 (0.64–0.79)). At 24h after surgery, the plasma levels of LDL-C (d: 0.73 (0.650.79)) and TC (d: 0.77 (0.69–0.82)) continued to decrease compared to preoperative levels, while the plasma levels of HDL-C (d: 0.46 (0.36–0.55)) and TG (d: 0.40 (0.29–0.50)) rebounded, but all remained below the preoperative levels (p < 0.001). Mortality at 30 days was 1.0% (N = 2/192), and 1-year mortality was 3.8% (N= 7/186). Postoperative myocardial infarction occurred in 3.1% of patients (N = 6/192) and postoperative stroke in 5.8% (N = 11/190). Adjusting for age, sex, BMI, and statin therapy, we noted a protective effect of postoperative occurrence of stroke for pre-to-post-operative changes in TC (adjusted odds ratio (OR) 0.29 (0.07–0.90), p = 0.047), in LDL-C (aOR 0.19 (0.03–0.88), p = 0.045), and in HDL-C (aOR 0.01 (0.00–0.78), p = 0.039). No associations were observed between lipid levels and 1-year mortality. In conclusion, cardiac surgery induces a significant sudden drop in levels of key plasma lipids. This effect was pronounced during the operation, and levels remained significantly lowered at 24 h after surgery. The intraoperative drops in LDL-C, TC, and HDL-C were associated with a protective effect against occurrence of postoperative stroke in adjusted models. We demonstrate that the changes in key plasma lipid levels during surgery are strongly correlated, which makes attributing the impact of each lipid to the clinical end points, such as postoperative stroke, a challenging task. Large-scale analyses should investigate additional clinical outcome measures.

Impact of Lipoprotein(a) Levels on Perioperative Outcomes in Cardiac Surgery

“…However, this best reflects current therapeutic research to selectively target Lp(a) levels with antisense oligonucleotides [ 8 ]. The effects of perioperative lipid status on clinical outcomes after cardiac surgery for the same cohort are described by Mihalj et al [ 25 ].…”

Discovery of plasma proteome markers associated with clinical outcome and immunological stress after cardiac surgery

“…This study is an analysis of the Bern Perioperative Biobank ( ClinicalTrials.gov ; NCT04767685; Submitted: December 16, 2020; principal investigator: Markus M Luedi), a prospective cohort of 192 adult patients undergoing non-emergency cardiac surgery at the Bern University Hospital between January 2019 and December 2019, described elsewhere ( 14 , 15 ). In brief, all patients underwent elective cardiac surgery (coronary artery bypass grafting, replacement or repair of aortic, mitral or tricuspid valves, surgery of the ascending aorta or aortic arch) with the use of conventional extracorporeal circulation circuits or minimally invasive extracorporeal circulation circuits ( 16 ).…”

“…The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE ( 17 ) partner repository with the dataset identifier PXD046496. Blood samples (EDTA) were collected before induction of general anaesthesia (preoperative) and 24 h after surgery (postoperative) and stored at the Bern Liquid Biobank as described before ( 14 , 15 ). Samples were diluted 10-fold in 5% sodium dodecyl sulphate, 100 mM triethylammonium bicarbonate pH 7.5 then centrifuged at 2,500 rcf for 15 min at ambient temperature.…”

The Role of Preoperative Chronic Statin Therapy in Heart Transplant Receipts—A Retrospective Single-Center Cohort Study

“…Moreover, elevated LDL-c levels independently predicted long-term cardiac death after coronary artery bypass graft [ 18 ]. On the other hand, it has been observed that, during cardiac surgery, the level of plasma lipids falls, having a protective effect on the occurrence of postoperative stroke [ 19 ].…”