Bypass Graft PCI Shows Higher Adverse Event Rate Compared to Native Artery PCI in Patients With Previous CABG

April 19, 2016—Emmanouil S. Brilakis, MD, et al conducted an investigation of percutaneous coronary intervention (PCI) in native coronary arteries versus bypass grafts in patients with previous coronary artery bypass graft (CABG) surgery. The study was published online ahead of print in the Journal of the American College of Cardiology (JACC): Cardiovascular Interventions. 

The aim of the study was to examine the frequency, associations, and outcomes of native coronary PCI versus bypass graft PCI in patients who underwent previous CABG in the Veterans Affairs (VA) integrated health care system. The national cohort of 11,118 veterans with previous CABG who underwent PCI between October 2005 and September 2013 at 67 VA hospitals was examined. The investigators compared the outcomes of patients who underwent native coronary PCI versus bypass graft PCI. 

As summarized in JACC: Cardiovascular Interventions, logistic regression with generalized estimating equations was used to adjust for correlation between patients within hospitals. Cox regressions were modeled for each outcome to determine the variables with significant hazard ratios (HRs).

During the study period, patients with previous CABG represented 18.5% of all patients undergoing PCI (11,118 of 60,171). The PCI target vessel was a native coronary artery in 73.4% of cases. The target vessel was the bypass graft in 26.6% cases: 25% in a saphenous vein graft and 1.5% in an arterial graft. 

The investigators reported that compared with patients undergoing native coronary artery PCI, those patients undergoing bypass graft PCI had higher risk characteristics and more procedure-related complications. During a median follow-up period of 3.11 years, bypass graft PCI was associated with significantly higher mortality (adjusted HR, 1.30; 95% confidence interval [CI], 1.18–1.42), myocardial infarction (adjusted HR: 1.61; 95% CI, 1.43–1.82), and repeat revascularization (adjusted HR: 1.6; 95% CI, 1.5–1.71).

In this national cohort of veterans, approximately three-quarters of PCIs performed in patients with previous CABG involved native coronary artery lesions. Compared with native coronary PCI, bypass graft PCI was significantly associated with higher incidence of short- and long-term major adverse events, including more than double the rate of in-hospital mortality, concluded the investigators in JACC: Cardiovascular Interventions.