Geographic disparity in 10-year mortality after coronary artery revascularization in the SYNTAXES trial

Aims: To investigate geographic disparity in long-term mortality following revascularization in patients with complex coronary artery disease (CAD). Methods and results: The SYNTAXES trial randomized 1800 patients with three-vessel and/or left main CAD to percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) and assessed their survival at 10 years. Patients were stratified according to the region of recruitment: North America (N-A, n = 245), Eastern Europe (E-E, n = 189), Northern Europe (N-E, n = 425), Southern Europe (S-E, n = 263), and Western Europe (W-E, n = 678), which also served as the reference group. Compared to W-E, patients were younger in E-E (62 vs 65 years, p < 0.001), and less frequently male in N-A (65.3% vs 79.6%, p < 0.001). Diabetes (16.0% vs 25.4%, p < 0.001) and peripheral vascular disease (6.8% vs 10.9%, p = 0.025) were less frequent in N-E than W-E. Ejection fraction was highest in W-E (62% vs 56%, p < 0.001). Compared to W-E, the mean anatomic SYNTAX score was higher in S-E (29 vs 31, p = 0.008) and lower in N-A (26, p < 0.001). Crude ten-year mortality was similar in N-A (31.6%), and W-E (30.7%), and significantly lower in E-E (22.5%, p = 0.041), N-E (21.9%, p = 0.003) and S-E (22.0%, p = 0.014). Compared to W-E, adjusted mortality in N-E (HR 0.85, p = 0.019) and S-E (HR 0.72, p = 0.043) remain significantly lower after adjustment for pre- and peri-procedural factors, but no significant interaction (P_interaction = 0.728) between region and modality of revascularization was seen. Conclusion: In the era of globalization, knowledge, and understanding of geographic disparity are of paramount importance for the correct interpretation of global studies.