From Pages to Practice
Published December 15, 2021
A 65-year-old man with a history of hypertension, overweight, and three-vessel coronary artery disease (CAD) is being evaluated for revascularization. Which surgery would reduce his risk of death most: percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) surgery?
Revascularization of coronary arteries can be performed electively or urgently for CAD with either PCI or CABG. In PCI, a catheter is typically accessed via the femoral or radial artery to provide access to coronary arteries, an expandable balloon is used to dilate the vessel by inflating the balloon at the site of the occlusion, and a stent (drug-eluting or bare metal) is placed at the site of the occlusion to maintain vessel patency. Various methods are used to assess the significance of stenosis during PCI. Fractional flow reserve (FFR)–guided PCI is the gold-standard for assessing the degree of coronary artery stenosis during coronary artery angiography and whether the degree of stenosis leads to symptoms of ischemia. FFR is the ratio of the blood flow in the presence of the stenosis to the theoretical normal blood flow of the coronary artery. A FFR measurement of ≤0.8 is considered functionally significant stenosis.
The selection of CABG versus PCI depends on a number of patient factors and including the number of vessels affected and the severity of stenosis. In patients with three-vessel coronary artery disease, CABG is considered superior to PCI. However, data on FFR-guided PCI is lacking.
In a noninferiority multicentered trial, Fearon and colleagues randomized 1500 patients with three-vessel disease to undergo CABG or FFR-guided PCI with drug-eluting stent. Noninferiority of FFR-guided PCI to CABG was prespecified as an upper limit of <1.65 for the 95% confidence interval (CI). The 1-year incidence of the primary composite endpoint (death, major cardiovascular event, or repeat revascularization) was higher (or not noninferior) with FFR-guided PCI versus CABG (10.6% vs. 6.9%; hazard ratio, 1.5). However, CABG was associated with a higher incidence of procedural complications (major bleeding 3.8% vs. 1.6%, acute kidney injury 0.9% vs. 0.1%, arrhythmia 14.1% vs. 2.4%, and 30-day rehospitalization, 10.2% vs. 5.5%).
In the case above, CABG generally would be preferred because it is associated with lower 1-year incidence of death, myocardial infarction, stroke, or repeat revascularization.
The following NEJM Journal Watch summary provides additional details of the study.
Howard C. Herrmann, MD, reviewing Fearon WF et al. N Engl J Med 2021 Nov 4
The advantages of coronary artery bypass graft (CABG) over percutaneous coronary intervention (PCI) have been most apparent in patients with the most-complex coronary artery disease (CAD). In this contemporary comparison, investigators assessed whether PCI with current drug-eluting stents and guided by fractional flow reserve (FFR) assessment could narrow this gap.
The industry-funded trial included 1500 patients with three-vessel CAD (without left main involvement) randomly assigned to CABG or FFR-guided PCI with zotarolimus-eluting stents. Their mean age was 65 years, 18% were women, 29% had diabetes, and 39% had acute coronary syndrome. Patients had an average of 4.3 lesions (22% of patients had at least 1 chronic total occlusion) and a mean SYNTAX score of 26. The mean numbers of stents (PCI) and distal anastomoses (CABG) received were 3.7 and 3.4, respectively.
At 1 year, the primary endpoint of death, myocardial infarction (MI), stroke, or repeat revascularization occurred in 10.6% of PCI patients and 6.9% of CABG patients. A secondary endpoint of death, MI, or stroke occurred in 7.3% and 5.2%, respectively. There was a trend toward better outcomes with PCI compared with surgery among patients with the lowest SYNTAX scores (<23). Patients undergoing CABG had higher rates of major bleeding, arrhythmia, acute kidney injury, and rehospitalization.
Comment: This study was designed to improve the results of PCI observed in prior comparisons with CABG in patients with complex CAD by using contemporary stents and practice with FFR guidance. However, PCI failed to meet noninferiority criteria at only 1 year of follow-up (3- and 5-year comparisons are planned). Surgical treatment was also improved from prior studies in the more-frequent use of arterial grafts and effective postoperative medical therapies. Overall, these results reinforce other studies demonstrating the superiority of surgery in patients with the most-complex CAD.