Non-diabetic patients with multivessel coronary artery disease (CAD) do better long-term with coronary artery bypass graft (CABG) surgery than with percutaneous coronary intervention (PCI), according to pooled patient-level trial data.
Compared with patients who got PCI with drug-eluting stents (DES), CABG recipients had a lower 5-year risk of death (6.7% versus 10.0%, hazard ratio [HR] 0.65, 95% CI 0.43-0.98), especially cardiac death (HR 0.41, 95% CI 0.25-0.78).
No clinical subgroup within the non-diabetic population showed a survival advantage with stenting, Cheol Whan Lee, MD, of Asan Medical Center in South Korea, and colleagues reported online in the Journal of the American College of Cardiology.
“There was no between-group difference within the first few months after randomization, but the difference progressively increased over time, demonstrating a clear survival advantage for CABG,” they wrote. Surgery is already recommended for diabetic patients with multivessel CAD at acceptable surgical risk, based on several trials favoring it over stenting.
The CABG cohort also had fewer cases of myocardial infarction (3.4% versus 8.9%, HR 0.40, 95% CI 0.24-0.65) and less need for repeat revascularization (HR 0.55, 95% CI 0.40-0.75) during follow-up. Stroke, on the other hand, occurred at similar frequency between groups (3.2% for CABG versus 2.9% for stenting, HR 1.13, 95% CI 0.59-2.17).
Myocardial infarction “tended to reach a plateau soon after CABG, whereas it continued to accrue over time after PCI with DES,” Lee’s group noted. “These findings are compatible with those from previous studies, supporting the idea that CABG may bypass the vulnerable segments of a coronary artery. Whereas DES treats the focal area of tight stenosis, CABG avoids touching risky sites and builds healthy connections that prevent future coronary events,” they suggested.
Their patient-level meta-analysis included 1,275 non-diabetic patients from the SYNTAX and BEST trials.
Those with SYNTAX scores from 23 to 32 had a clear survival advantage with CABG, whereas PCI appeared to perform similarly as well for those with higher and lower scores.
“Decision making for nondiabetic patients with multivessel CAD should be individualized. If equipoise between CABG and PCI exists, decision-making can be improved by engaging a local multidisciplinary CAD heart team,” Farouc A. Jaffer, MD, PhD, of Massachusetts General Hospital, and Patrick T. O’Gara, MD, of Brigham and Women’s Hospital, both in Boston, wrote in an accompanying editorial.
Also, “an informed patient’s values and preferences should be clearly identified and respected,” they added. “Younger patients may be more willing to accept the upfront risks associated with CABG to realize a long-term mortality benefit. In contrast, elderly or frail patients may prefer to focus on a shorter time horizon and prefer the lower upfront risks often available with PCI.”
The editorialists also emphasized fair, careful discussion with patients about their revascularization strategy, because “bias can easily be introduced as reflected in a tone of voice, body language, or pre-conceived notions of a superior approach.”
One potential confounder in the study was that optimal medical therapy was used less often after CABG than PCI, Lee and colleagues acknowledged.
Jaffer and O’Gara pointed out other limitations for the meta-analysis. Besides the exclusion of patients with complex disease, they noted that the majority of the study population was derived from the SYNTAX trial, which used first-generation paclitaxel DES that are associated with more complications than the newer-generation stents.
The investigators, however, wrote that subgroup analysis showed no interaction between previous and newer-generation DES on survival. “In this regard, CABG seems to maintain a comparative advantage over PCI, even in the era of newer-generation DES,” they concluded.
But for the editorialists, it’s not just about the type of stent used — PCI approaches seem to be evolving for the better as well.
“Although complete revascularization was more frequently obtained with CABG in the SYNTAX and BEST trials, current PCI approaches are narrowing this gap with chronic total occlusion PCI techniques and temporary hemodynamic support when needed.”
The study was supported by a grant from Korea’s CardioVascular Research Foundation (CVRF).
Lee and O’Gara reported no relevant conflicts of interest.
Jaffer declared receiving research grants from Siemens and Kowa.
Journal of the American College of Cardiology
Chang M, et al “Long-term mortality after coronary revascularization in nondiabetic patients with multivessel disease” J Am Coll Cardiol 2016; DOI: 10.1016/j.jacc.2016.04.034.
Journal of the American College of Cardiology
Jaffer FA, et al “Multivessel CAD in nondiabetic patients: to operate or to dilate?” J Am Coll Cardiol 2016; DOI: 10.1016/j.jacc.2016.05.008.