Updated Guidelines: Coronary Artery Bypass Grafting and Percutaneous Coronary Intervention

Background and Purpose: These new coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) guidelines update versions from 2004 and 2007, respectively. Unique to the revisions is a joint set of recommendations produced collaboratively to address the question of which patients should undergo which procedure. Additional input was also provided by the authors of the ACC/AHA guidelines on management of stable ischemic heart disease (JW Cardiol Dec 12 2007; revision expected in 2012) and unstable angina/non-ST-segment-elevation myocardial infarction (JW Cardiol Apr 20 2011).

Key Points:

1. Because data from trial registries show lower mortality rates in patients referred for a specific procedure compared with patients in concurrent randomized cohorts, these guidelines contain a new Class I recommendation for a multidisciplinary heart team (MHT) to coordinate care of patients with left main or complex coronary artery disease (CAD). The MHT includes an interventional cardiologist and a cardiac surgeon who jointly develop a revascularization plan to present to the patient for a final decision. A new recommendation for the use of transesophageal echocardiography during CABG (Class IIa) supports the inclusion of a cardiac anesthesiologist on the MHT.

2. The authors encourage the use of the SYNTAX and STS scoring systems in formulating revascularization decisions (Class IIa). This recommendation reflects a trend away from simple angiographic criteria toward a more integrated approach that incorporates functional assessment of lesion severity with measures such as fractional flow reserve.

3. PCI is now recognized as a reasonable alternative to CABG for unprotected left main lesions (Class designation raised to IIa from IIb) when anatomy is favorable for PCI and surgical risk is high. CABG retains a Class I indication for unprotected left main lesions and is also preferred (Class IIa) for most patients with three-vessel disease.

4. In separating survival indications from symptom relief, the authors now recommend PCI for angina that persists despite “guideline-determined medical therapy” (Class I), on the basis of findings from the COURAGE trial (in which the term “optimal medical therapy” was used; JW Cardiol Mar 26 2007).

5. Many recommendations pertain to appropriate medical therapy before and after PCI and CABG:

• High-dose statin therapy is recommended before PCI (Class IIa).

• The recommended aspirin dose after PCI has been reduced to 81 mg per day (Class IIa).

• Ticagrelor now carries a Class I recommendation as an alternative to clopidogrel or prasugrel for 12 months after stenting.

• Aspirin and beta-blockers are recommended before CABG (Class I).

• Clopidogrel and ticagrelor should be discontinued 5 days before elective CABG and 24 hours before emergency CABG (Class I).

• After CABG, patients should receive beta-blockers, statins, and intravenous insulin to maintain a blood glucose of <180 mg/dL (Class I).

6. N-acetylcysteine is no longer recommended for PCI in patients at risk for acute kidney injury (Class III).

7. Hybrid revascularization, off-pump CABG, and use of robotic techniques are discussed. Hybrid revascularization is deemed reasonable in patients with aortic, target-vessel, or conduit constraints to traditional CABG (Class IIa).