For noncomplex, unprotected left main coronary artery disease (CAD), the choice between coronary artery bypass grafting (CABG) and drug-eluting stents (DES) can be a toss-up, a single-center study suggested.
Stenting and surgery yielded similar combined rates of death, nonfatal myocardial infarction, and nonfatal stroke (7.5% versus 9.4%, HR 0.94, 95% CI 0.82-1.09), Sheng-Shou Hu, MD, PhD, of China’s Fuwai Hospital, and colleagues reported online in JACC: Cardiovascular Interventions.
After adjustment for baseline differences, stenting was associated with higher odds of death (3.8% versus 2.5% with CABG, hazard ratio [HR] 1.71, 95% CI 1.32-2.21) and repeat revascularization by 3 years (9.9% versus 2.1%, HR 4.91, 95% CI 3.91-6.16).
But it was only for those with a SYNTAX score above 32 that percutaneous coronary intervention (PCI) was tied to an increased risk of mortality (HR 3.10, 95% CI 1.84-5.22) and combined events (HR 1.82, 95% CI 1.36-2.45).
Patients scoring below 32 saw no difference in risk of death between stenting and surgery but were less likely to have combined 3-year adverse events when they got stenting with DES (6.6% versus 9.7% for CABG, HR 0.74, 95% CI 0.59-0.94). On the other hand, these patients had more repeat revascularizations with PCI (9.9% versus 2.4%, HR 4.10, 95% CI 2.92-5.75).
“With optimal clinical judgment and appropriate strategy selection in unprotected left main disease treatment setting, satisfactory 3-year outcomes could be achieved with either CABG or PCI in contemporary practice,” they wrote. Yet “for patients with less complex disease (low or intermediate SYNTAX scores), PCI is a reasonable alternative treatment to CABG whereas greater survival benefit of CABG over PCI was found in patients with high SYNTAX scores.”
Survival rates greatly favored CABG for those with left ventricular ejection fractions under 50% (10.3% mortality rate for PCI versus 1.6% for surgery, HR 6.99, 95% CI 2.48-19.7), as well as those with unprotected left main bifurcations (4.3% versus 3.6%, HR 2.48, 95% CI 1.66-3.72).
Stroke, however, was less common after PCI (1.1% versus 4.4%, HR 0.18, 95% CI 0.13-0.26).
“The survival benefit after CABG needs to be balanced against the risk of stroke,” Hu and colleagues wrote. “The cause of stroke after revascularization is multifactorial, and the low rate of stroke among patients who underwent PCI might have resulted from the use of highly effective dual antiplatelet therapy, which prevents thromboembolic events.”
In accompanying editorial, Cheol Whan Lee, MD, of Asan Medical Center, and Mineok Chang, MD, of Seoul St. Mary’s Hospital, both in Korea, proposed that “PCI with DES is the better treatment option for selected patients with less complex left main CAD.”
“Significant left main CAD may potentially increase the risk for early and late cardiovascular events following CABG,” according to the duo. “Hemodynamic instability after surgical manipulation and early graft failure might be catastrophic to patients with left main CAD because a large area of the left ventricle is affected by disturbance in the left main coronary flow. Likewise, severe left main CAD may progress to total occlusion after CABG surgery because of low and oscillating shear stress, which might make graft failure more catastrophic because of large ischemic burden.”
Hu’s observational study included 4,046 consecutive patients who got stenting or surgery between 2004 and 2010. SYNTAX scores exceeded 32 for 31.2% of the cohort.
Diabetes patients had similar mortality rates no matter the treatment they received (2.9% for PCI versus 3.0% for CABG, HR 1.10, 95% CI 0.70-1.75), but after stenting showed fewer combined events (7.3% versus 11.7%, HR 0.66, 95% CI 0.51-0.87) and more repeat revascularizations (12.2% versus 1.9%, HR 6.74, 95% CI 4.38-10.37).
The authors counted the observational, single-center nature of their study among its caveats due to the potential for unmeasured confounders. Repeat revascularization without further information about the vessel targeted was another limitation, they added, and certain subgroups were underrepresented.
Hu, Lee, and Chang disclosed no relevant conflicts of interest.
JACC: Cardiovascular Interventions
Zheng Z, et al “Coronary artery bypass graft surgery and percutaneous coronary interventions in patients with unprotected left main coronary artery disease” JACC Cardiovasc Interv 2016; DOI: 10.1 016/j.jcin.2016.03.039.
JACC: Cardiovascular Interventions
Lee CW and Chang M “A simple, effective, and durable treatment choice for left main coronary artery disease: stents or surgery?” JACC Cardiovasc Interv 2016; DOI: 10.1016/j.jcin.2016.04.015.