From the Guidelines
After coronary artery bypass grafting (CABG), cholesterol levels should be rechecked within 4-6 weeks post-surgery and then every 3-6 months until targets are achieved, followed by annual monitoring, with a primary target of LDL cholesterol below 70 mg/dL, as recommended by the most recent guidelines 1. The management of hyperlipidemia after CABG is crucial to reduce the risk of future cardiovascular events. According to the 2011 ACCF/AHA guideline for coronary artery bypass graft surgery, all patients undergoing CABG should receive statin therapy, unless contraindicated, with an adequate dose to reduce low-density lipoprotein cholesterol to less than 100 mg/dL and achieve at least a 30% lowering of low-density lipoprotein cholesterol 1. However, more recent guidelines suggest a more aggressive approach, with a target LDL-C level of less than 70 mg/dL, and consideration of combination therapy with ezetimibe and PCSK9 inhibitors for high-risk patients 1. Some key points to consider in the management of hyperlipidemia after CABG include:
- High-intensity statin therapy, such as atorvastatin 40-80 mg daily or rosuvastatin 20-40 mg daily, starting as soon as the patient can take oral medications after surgery
- Addition of ezetimibe 10 mg daily if LDL targets are not achieved with maximum tolerated statin therapy
- Consideration of PCSK9 inhibitors (evolocumab or alirocumab) for patients still not at goal
- Monitoring of non-HDL cholesterol (target <100 mg/dL) and triglycerides (<150 mg/dL) The most recent guidelines emphasize the importance of early and aggressive lipid-lowering therapy in patients with established atherosclerotic cardiovascular disease, including those who have undergone CABG, to reduce the risk of recurrent events and improve outcomes 1.
From the Research
Guidelines for Rechecking Cholesterol Levels
- The European dyslipidaemia guidelines (2019 and 2016) define target LDL-C as <1.4 mmol/L (54 mg/dL) and <1.8 mmol/L (70 mg/dL), and target non-HDL-C as <2.2 mmol/L (85 mg/dL) and <2.6 mmol/L (100 mg/dL) 2.
- Patients undergoing coronary artery bypass graft (CABG) surgery should have their lipid profiles checked at least 3 weeks post-operatively, with follow-up lipid results available for analysis 2.
Targets for Cholesterol Levels
- The goal of LDL-C <1.4 mmol/L was attained in only 14.9% of patients 1 year after CABG, and the goal of LDL-C <1.8 mmol/L was attained in 47.7% of patients 2, 3.
- Non-HDL-C levels <2.2 mmol/L and <2.6 mmol/L were attained in 28.9% and 49.0% of patients, respectively 2.
Medical Therapy after CABG
- Statin therapy is the mainstay of secondary prevention after CABG, with high-intensity statins prescribed for 90.6% of patients 2, 4.
- PCSK-9 inhibitors should be used in patients with elevated LDL cholesterol despite maximally tolerated statin therapy, and icosapent ethyl should be considered in patients with elevated triglycerides despite maximally tolerated statin therapy 5.
- Long-acting GLP-1 receptor agonists or SGLT-2 inhibitors should be used in all post-CABG patients with type 2 diabetes 5.
Association between LDL-C Levels and Long-Term Outcomes
- The LDL-C levels at 1-year post-CABG were independently associated with long-term major adverse cardiovascular and cerebrovascular events (MACCEs) 3.
- Patients with LDL-C ≥2.60 mmol/L had a higher risk of long-term MACCEs, cardiac death, nonfatal myocardial infarction, nonfatal stroke, revascularization, and cardiac rehospitalization compared to patients with LDL-C <1.40 mmol/L 3.