Impact of Target Lesion Revascularization on Long-Term Mortality After Percutaneous Coronary Intervention for Left Main Disease.

Background: Although target lesion revascularization (TLR) after percutaneous coronary intervention (PCI) for unprotected left main coronary artery (LMCA) disease is not rare, its timing of occurrence and prognostic impact on long-term mortality is uncertain.

Objectives: This study sought to investigate TLR incidence over time and its impact on mortality after PCI with drug-eluting stents (DES) for LMCA disease.

Methods: Using a pooled data from 4 multicenter observational registries (IRIS-DES [Interventional Cardiology Research Incorporation Society-Drug-Eluting Stents], IRIS-MAIN [Interventional Cardiology Research Incorporation Society-Left MAIN Revascularization], MAIN-COMPARE [Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization], and PRECOMBAT [PREmier of Randomized COMparison of Bypass Surgery versus AngioplasTy Using Drug-Eluting Stent in Patients with Left Main Coronary Artery Disease]), we evaluated 1,397 patients with LMCA disease treated with DES and available long-term mortality data. The association between TLR and the 10-year risk of mortality was examined by multivariable Cox proportional hazards regression, with TLR as a time-varying covariate.

Results: During maximum follow-up of 10 years (median 6.8 years), TLR occurred in 118 patients and its 10-year cumulative incidence was 10.8%. TLR mostly occurred within 2 years after initial PCI and decreased over time: early-stage TLR (within 2 years) in 73 (61.9%) patients and late-stage TLR (beyond 2 years) in 45 (38.1%) patients. Among all TLR patients, 23 patients underwent coronary artery bypass grafting and 95 underwent repeat PCI. In the time-varying multivariable Cox model, the presence of TLR was not significantly associated with an increased risk of mortality (adjusted HR: 0.90; 95% CI: 0.50-1.63; P = 0.73).

Conclusions: Although the incidence of ischemia-driven TLR was mostly common within 2 years after left main PCI, TLR occurred steadily during the 10-year follow-up period. However, given that such patients were optimally revascularized, the prognostic impact of TLR on mortality was not substantial. (Evaluation of the First, Second, and New Drug-Eluting Stents in Routine Clinical Practice [IRIS-DES]; NCT01186133; Observational Study for Left Main Disease Treatment [IRIS-MAIN]; NCT01341327; Ten-Year Outcomes of Stents Versus Coronary-Artery Bypass Grafting for Left Main Coronary Artery Disease [MAIN COMPARE]; NCT02791412; Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease [PRECOMBAT]; NCT00422968).