Criteria for direct myocardial revascularization in patients with left main coronary artery stenosis

Objective. To determine the objective indications and long-term outcomes of direct myocardial revascularization taking into account anatomy of left main coronary artery (LMCA) lesion. Material and methods. We analyzed baseline coronary angiography (CAG) data from 723 patients with LMCA disease (stenosis ≥50%) and long-term CAG results (67+9 months) in 283 patients who underwent surgery between 2010 and 2023. Severity of coronary artery disease was assessed using the DEFINITION and Syntax Score criteria. Results. The most common location of lesion was distal LMCA stenosis involving the bifurcation (250 (88.3%) cases). Complete revascularization (rSS-0) was achieved in 97.2% of patients. Analysis of two coronary artery (CA) lesion classifications (DEFINITION vs. Syntax Score) revealed that 30.6% of patients with Syntax score <22 had complex LMCA lesion involving the bifurcation as defined by the DEFINITION classification. These lesions make adequacy and long-term effectiveness of endovascular intervention questionable and are an indication for direct revascularization, as well as vice versa. Satisfactory conduit function was demonstrated in 85.4% of cases in long-term period. Furthermore, patency of the left and right internal mammary arteries, as well as venous bypass grafts was 92.2%, 88.4%, and 81.7%, respectively. Conclusion. The DEFINITION classification provides fundamentally important and comprehensive information on anatomy and topography of LMCA lesions. It may be included in descriptive examination program for patients with LMCA stenosis.