No significant difference was observed in all-cause mortality at 10 years between PCI and CABG in patients with unprotected left main coronary artery disease (CAD) and no additional complex lesions, according to the final results of the NOBLE study published April 4 in The Lancet.

In the prospective, open-label noninferiority NOBLE trial, 1,201 eligible patients were randomly assigned to either PCI (n=598) or CABG (n=603) from Dec. 9, 2008, through Jan. 21, 2015. Eligibility was defined by clinical criteria (chronic or acute coronary syndrome and a life expectancy of more than one year) and angiographic criteria (left main coronary artery diameter stenosis ≥50% or fractional flow reserve ≤0.80 in the left main ostium, mid-shaft or bifurcation). Of note, researchers excluded patients with STEMI within 24 hours and patients considered too high-risk for either treatment.

Conducted at 36 hospitals in northern Europe, patients were stratified by site, sex, diabetes and distal left main coronary artery bifurcation lesions. Emil Nielsen Holck, MD, PhD, et al., used Kaplan-Meier estimates and unadjusted Cox regression to analyze the primary outcome of the difference in 10-year all-cause mortality in the intention-to-treat (ITT) population. Variation in all-cause mortality was assessed in prespecified subgroups.

Seventeen patients were lost to follow-up before one year, leaving 592 patients per group in the ITT population. The mean age was 66 years in both groups, and 78% of participants were male.

At the 10-year follow-up, all-cause mortality did not differ significantly between the PCI and CABG arms (23% vs. 25%; hazard ratio, 0.93, 95% CI, 0.74-1.18; p=0.56). Additionally, no significant interaction between SYNTAX score and all-cause mortality was observed.

“…this long-term follow-up study might affect future guidelines for patients with acute and chronic coronary syndrome by supporting more nuanced patient-centered decisions,” write Nielsen and colleagues. “These results will aid heart teams in developing an individualized patient-centered strategy and inform shared decision making and future guideline recommendations.”

In an accompanying editorial, Kuniaki Takahashi, MD, and William F. Fearon, MD, FACC, note that “these final results from NOBLE provide valuable long-term insight and rather than resolving the debate, these data refine it.” They emphasize that the central task for physicians is “to individualize the treatment strategy based on anatomical complexity, clinical presentation, comorbidity profile, patient preferences, operator expertise and local volumes through multidisciplinary heart team discussions.”