Patients with unprotected left main disease were generally more likely to have repeat revascularization after percutaneous coronary intervention (PCI) instead of coronary artery bypass grafting (CABG), a study found, though investigators observed fewer deaths in select groups.
The rate of major adverse cardiac and cerebrovascular events within 5 years favored CABG recipients (23.0% versus 28.3% for PCI, HR 1.23, 95% CI 1.01-1.55), a result mostly driven by the link between repeat revascularization and PCI (HR 1.85, 95% CI 1.38-2.47), reported Patrick W. Serruys, MD, PhD, of Imperial College London, and colleagues in the Journal of the American College of Cardiology.
CABG and PCI groups had similar odds of combined death, myocardial infarction (MI), and stroke (16.8% versus 14.3%, HR 0.90, 95% CI 0.67-1.19). Individual endpoints yielded similar results at 5 years:
- All-cause death: 11.1% versus 9.4% (HR 0.83, 95% CI 0.59-1.16)
- Cardiac death: 6.8% versus 6.2% (HR 0.90, 95% CI 0.59-1.37)
- MI: 3.2% versus 5.2%, (HR 1.58, 95% CI 0.92-2.72)
- Stroke: 2.5% versus 1.1%, HR 0.42, 95% CI 0.17-1.02)
After PCI in lieu of CABG, patients with left main disease coupled with involvement of up to one other vessel did, however, have reduced odds of all-cause mortality (HR 0.40, 95% CI 0.20-0.83) and cardiac mortality (HR 0.33, 95% CI 0.12-0.88)
“Our results are reassuring in regard to equivalent long-term results between the 2 treatment strategies and potentially better outcomes in patients with isolated left main or left main + 1-vessel disease with PCI,” the authors concluded.
“The equipoise between PCI and CABG for the safety composite endpoint is clinically meaningful and reassuring as both myocardial infarction and stroke are associated with impaired prognosis, whereas repeat revascularization procedures mainly affect quality of life,” commented Stephan Windecker, MD, and Raffaele Piccolo, MD, both of Bern University Hospital in Switzerland, in an accompanying editorial.
“Of note, there was no specific subgroup in which CABG outperformed PCI with respect to long-term mortality,” Windecker and Piccolo wrote.
“Even 1 decade ago, PCI in patients with left main disease was not recommended by guidelines on both sides of the Atlantic, whereas more recently, PCI has emerged as a valid alternative to CABG among patients with low and intermediate anatomic complexity.”
Nonetheless, the editorialists wrote, “CABG will remain the treatment of choice among patients with advanced left main disease owing to the protection against proximal atherosclerosis progression, the remarkable decrease in the need for repeat revascularization (~70% relative reduction), and the more complete revascularization.”
“These long-term benefits clearly outweigh the risk of peri-procedural complications including the higher rate of stroke,” they noted.
Serruys and his group pooled data from patients with left main disease enrolled in the SYNTAX and PRECOMBAT trials (n=1,305). Patients were randomized to either PCI or CABG; in the PCI group, they got paclitaxel-eluting Taxus stents and sirolimus-eluting Cypher stents in the SYNTAX and PRECOMBAT trials, respectively.
SYNTAX II scores corresponded with rates of adverse events.
Among the limitations of the pooled analysis were the differing definitions of MI and stroke between the two trials.
In addition, the authors acknowledged the lack of newer-generation drug-eluting stents in both studies, while pointing out that the ongoing EXCEL and NOBLE randomized trials may provide clues on whether newer stents can do better.
Windecker and Piccolo called said these studies were “eagerly expected,” citing the inclusion only of patients with left main disease and simple-to-moderately complex disease.
Until the results are made public, “the selection of the most appropriate revascularization strategy among patients with left main disease disease should follow the principles outlined in recent guideline documents,” they suggested.
Serruys and most co-authors disclosed no relevant relationships with industry. One co-author disclosed a relevant relationship with Abbott Vascular.
Windecker disclosed support from Abbott, Boston Scientific, Biotronik, Medtronic, Edwards, and St. Jude Medical.
Piccolo disclosed support from the Veronesi Foundation.
Journal of the American College of Cardiology
Cavalcante R, et al “Outcomes after percutaneous coronary intervention or bypass surgery in patients with unprotected left main disease” J Am Coll Cardiol 2016; DOI: 10.1016/j.jacc.2016.06.
Journal of the American College of Cardiology
Windecker S, et al “Myocardial revascularization for left main coronary artery disease: a step toward individualized treatment selection” J Am Coll Cardiol 2016; DOI:10.1016/j.jacc.2016.06.043.