Unprotected left main coronary artery (LMCA) disease remains one of the most severe forms of coronary artery disease, historically treated with coronary artery bypass grafting (CABG). However, with the advancement of drug-eluting stents (DES), percutaneous coronary intervention (PCI) has emerged as a valid alternative for selected patients. The NOBLE trial was designed to compare long-term outcomes between the two revascularization strategies in patients with significant unprotected LMCA disease.

This was a prospective, randomized, multicenter study conducted across 36 hospitals in Nordic and Baltic countries, the United Kingdom, and Germany, enrolling a total of 1,201 patients between December 2008 and January 2015. Inclusion criteria required LMCA stenosis ≥50% or FFR ≤0.80, with Heart Team consensus confirming that comparable revascularization could be achieved by either approach. Exclusion criteria included chronic total occlusions, bifurcations requiring double-stent technique, highly calcified or tortuous anatomy, ST-elevation myocardial infarction within 24 hours, and life expectancy <1 year. Patients were randomized to PCI (n = 598) with biolimus-eluting stent (BioMatrix, Biosensors) or to CABG (n = 603).
The primary endpoint was all-cause mortality at 10 years. Secondary endpoints included cardiovascular mortality, myocardial infarction (MI), repeat revascularization, and subgroup analyses based on acute coronary syndrome (ACS) or chronic coronary syndrome (CCS), along with stratification by SYNTAX score.
At 10 years, all-cause mortality was 23% in the PCI group vs 25% in the CABG group (HR 0.93; 95% CI 0.74–1.18; p = 0.56), showing no significant difference. Subgroup analyses revealed no differences in patients with chronic coronary syndrome (HR 1.04; 95% CI 0.80–1.34; p = 0.78), whereas in those with ACS, PCI showed lower mortality (HR 0.57; 95% CI 0.32–0.99; p = 0.047). There was no significant interaction with the SYNTAX score: <23 (HR 1.13; p = 0.51), 23–32 (HR 0.75; p = 0.10), and >32 (HR 0.94; p = 0.86).
Conclusion
At 10 years of follow-up, the NOBLE trial demonstrated similar overall mortality between PCI and CABG in patients with significant unprotected left main coronary artery disease. No differences were found in cardiovascular mortality or in the temporal evolution of adverse events, although PCI was associated with lower mortality among patients with ACS. These findings reinforce PCI as a valid alternative to surgery in selected cases.
Presented by Evald Christiansen on behalf of the NOBLE Study Group. Presented on October 27 at TCT 2025 (Late-Breaking Clinical Trials), San Francisco, USA.
Subscribe to our weekly newsletter
Get the latest scientific articles on interventional cardiology





