In patients with prior coronary artery bypass graft (CABG) surgery, revascularization yielded worse outcomes if done in the graft rather than a native coronary artery, a multicenter study suggested, although the predominance of saphenous vein grafts treated might have had a role.
Although patients undergoing bypass graft percutaneous coronary intervention (PCI) had higher risk characteristics to begin with, the poorer outcomes persisted after multivariable adjustment. Compared with native artery PCI patients, more had persistent blockage with no reflow achieved in-hospital (3.37% versus 0.40%, odds ratio [OR] 7.0, 95% confidence interval [CI] 4.8-10.3) and periprocedural myocardial infarction (MI, 1.00% versus 0.43%, OR 2.3, 95% CI 1.1-4.7).
Risks continued after discharge as well, Emmanouil S. Brilakis, MD, PhD, of University of Texas Southwestern Medical Center in Dallas, and colleagues reported online in JACC: Cardiovascular Interventions. Over a median follow-up of 3.11 years, graft versus native artery PCI showed:
- More deaths (hazard ratio [HR] 1.30, 95% CI 1.18-1.42)
- More MIs (HR 1.61, 95% CI 1.43-1.82)
- More repeat revascularization (HR 1.60, 95% CI 1.50-1.71)
“The improved short- and long-term outcomes observed suggest that native coronary arteries should be the preferred PCI target vessels for prior CABG patients, whenever possible,” the authors reported
Yet the results may not be all too surprising given that the bypass grafts treated were largely saphenous vein graft (SVG) lesions, according to the investigators.
“SVG lesions are often degenerated, complex lesions that may predispose to distal embolization. Indeed SVG PCI was associated with higher risk of no reflow and periprocedural myocardial infarction in our study, even though embolic protection devices are used more commonly in the Veterans Affairs system,” Brilakis and colleagues wrote.
Even with the use of second-generation drug-eluting stents, repeat revascularization after SVG PCI is “likely due to higher rates of inflammation and thrombus formation,” they added.
Brilakis’ retrospective investigation included a cohort of 11,118 patients, those identified in the national Veterans Affairs Clinical Assessment, Reporting, and Tracking program as prior CABG recipients. Participants had subsequent PCI between 2005 and 2013.
The target vessel was a native coronary artery in 73.4% of patients and a bypass graft in 26.6%. Those getting bypass graft PCI were older and more likely to have diabetes, chronic kidney disease, and acute coronary syndromes.
Brilakis disclosed relationships with Abbott Vascular, Boston Scientific, Elsevier, InfraRedx, Somahlution, St. Jude Medical, and Terumo. His spouse is an employee of Medtronic.
JACC: Cardiovascular Interventions
Brilakis ES, et al “Percutaneous coronary intervention in native coronary arteries vs. bypass grafts in patients with prior coronary artery bypass graft surgery: insights from the veterans affair CART program” JACC Cardiovasc Interv 2016.