Stroke: Stenting or Bypass Surgery?

November 11, 2016
Veronica Hackethal, MD

Patients with left main CAD of low or intermediate anatomical complexity were treated with PCI with everolimus-eluting stents or CABG.

For patients with low or intermediate anatomic complexity left main coronary artery disease (CAD), percutaneous coronary intervention (PCI) with everolimus-eluting stents may result in outcomes similar to coronary artery bypass graft (CABG), according to results from the XIENCe vs Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization (EXCEL) study published online in the New England Journal of Medicine.1

“The results of the EXCEL trial suggest that PCI with everolimus-eluting stents is an acceptable or perhaps preferred alternative to CABG in selected patients with left main coronary artery disease who are candidates for either procedure,” wrote first author Gregg Stone, MD, of Columbia University Medical Center (NYC, NY) and colleagues.

US and European guidelines recommend CABG for individuals with left main CAD.2,3 However, some randomized controlled trials (RCTs) have suggested that PCI using drug-eluting stents could be an alternative for some patients with low or intermediate anatomical complexity disease. Since those trials began, surgical techniques have continued to improve. Everolimus-eluting stents have also been introduced and have lower rates of thrombosis than paclitaxel-eluting stents, raising the question of whether PCI may now be a better alternative for some patients with left main CAD.

The open-label RCT included 1905 participants enrolled between September 2010 and March 2014 at 126 sites in 17 countries. Participants had left main CAD of low or intermediate anatomical complexity, as determined using the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score. Participants were randomized to PCI with fluoropolymer-based cobalt–chromium everolimus-eluting stents (XIENCE, Abbott Vascular) (n=948), or CABG (n=957). The primary endpoint consisted of composite rate of death from any cause, stroke, or myocardial infarction (MI) at 3 years. Secondary endpoints included a composite rate of death from any cause, stroke, or MI at 30 days, and the composite rate of death, stroke, MI, or ischemia-driven revascularization at three years.

Key Results:

• Primary endpoint at three years:

♦ PCI: 15.4%

♦ CABG: 14.7%

♦ Difference between the two groups met prespecified noninferiority criteria (P=0.02 for noninferiority; HR 1.00; 95% CI, 0.79 to 1.26; P=0.98 for superiority)

• Secondary endpoint for death, stroke, or myocardial infarction at 30 days:

♦ PCI group: 4.9%

♦ CABG group: 7.9%

♦ P<0.001 for noninferiority, P=0.008 for superiority

• Secondary endpoint for death, stroke, myocardial infarction, or ischemia-driven revascularization at 3 years:  

♦ PCI group: 23.1%

♦ CABG group: 19.1%

♦ P=0.01 for noninferiority, P=0.10 for superiority

The authors noted that PCI carried a three-year rate of revascularization that was 5% higher than CABG, although rates of early MI and major adverse events (bleeding, infection, major arrhythmia, and renal failure) were 15% lower with PCI compared to CABG.

PCI patients experienced significantly fewer periprocedural adverse events within 30 days after randomization, compared to CABG patients (8.1% vs 23.0%, P<0.001), mainly due to fewer major arrhythmias, fewer infections requiring antibiotics, and fewer blood transfusions.

Limitations include lack of blinding due to the nature of the procedures. Despite protocol, 24% of randomized patients had SYNTAX scores suggesting high anatomical complexity. Also, because of differences in practice patterns, long-term medication differed between the PCI and CABG groups. The authors noted that further studies are needed to determine the suitability of PCI as an acceptable alternative to CABG in patients with CAD of high anatomical complexity, and whether differences in medical management contributed to the results. 

Longer-term outcomes are also needed to determine whether these results persist over time. Researchers are currently conducting a five-year follow-up study.

Take-home Points

• Results from the EXCEL trial suggest that PCI with everolimus-eluting stents is an acceptable or perhaps preferred alternative to CABG in patients with low to intermediate anatomic complexity left main CAD.

• Results at three years showed that the composite rate of death from any cause, stroke, or myocardial infarction was not inferior for PCI with everolimus-eluting stents compared to CABG in these patients.

• Three-year rates of revascularization were higher with PCI vs CABG.

• Rates of early MI, major adverse events, and periprocedural adverse events were lower with PCI vs CABG.

• A five-year outcomes study is underway.

The trial was sponsored by Abbott Vascular.

One or more authors reports consulting fees, holding equity and/or stock, institutional and/or personal royalties, training fees, research funding, advisory board and/or executive committee membership, institutional and/or personal grant support, lecture fees from one or more of the following: Velomedix, Toray, Matrizyme, Miracor, TherOx, Reva, V-Wave, Vascular Dynamics, Ablative Solutions, Neovasc, Medical Development Technologies, Lupin Pharmaceuticals, MedFocus family of funds, Guided Delivery Systems, Micardia, Vascular Nanotransfer Technologies, Cagent, Qool Therapeutics, Caliber Therapeutics, Aria, and the Biostar family of funds, Abbott Vascular, Medtronic, the Sorin Group, Edwards Lifesciences, AstraZeneca, Biotronik, Cardialysis, GLG Research, Sinomedical Sciences Technology, Stentys France, Svelte Medical Systems, Volcano, St. Jude Medical, Boston Scientific, Cardiovascular Systems,  Scanlan, Biotronik, Medinol, Watermark Research Partners, Janssen Pharmaceuticals, Osprey Medical, the Medicines Company, Medscape, Merck, Cardiovascular Systems, Sanofi, Shanghai BraccoSine Pharmaceuticals, Eli Lilly/Daiichi-Sankyo, Bristol-Myers Squibb, AstraZeneca, the Medicines Company, OrbusNeich, Bayer, CSL Behring, Abbott Laboratories, Novartis Pharmaceuticals, and/or AUM Cardiovascular.  

Dr. Simonton has been an employee of Abbott Vascular.

References:

1. Stone GW, et al for the EXCEL Trial Investigators. Everolimus-eluting stents or bypass surgery for left main coronary artery disease. N Engl J Med. 2016 Oct 31.

2. Fihn SD, et al. 2014 ACC/AHA/AATS/PCNA/SCAI/STS focused update of the guideline for the diagnosis and management of patients with stable ischemic heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines, and the American Association for Thoracic Surgery, Preventive Cardiovascular Nurses Association, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. J Am Coll Cardiol 2014;64:1929-1949.

3. Windecker S, et al. 2014 ESC/EACTS Guidelines on myocardial revascularization: The Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS) developed with the special contribution of the European Association of Percutaneous Cardiovascular Interventions (EAPCI). Eur Heart J 2014;35:2541-2619.