P4587Impact of diabetes mellitus on myocardial revascularisation method in the light of the 2018 ESC/EACTS guidelines: Results from the PROUST Study

Results of currently available randomized trials have shown divergent outcomes in diabetic patients undergoing percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). The 2018 ESC/EACTS guidelines on myocardial revascularization do not recommend PCI in patients with diabetes and SYNTAX score ≥23. We aimed to compare the all-cause 4-year mortality after revascularization for complex coronary artery disease (CAD) in diabetics. The study group comprised consecutive diabetics with angiographically proven three-vessel CAD (≥50% diameter stenosis) and/or unprotected left main CAD (≥50% diameter stenosis) without major hemodynamic instability, who were treated in two institutions with PCI or referred for CABG between 2008 and 2010. All-cause mortality was ascertained by telephone contacts and/or from Mortality Registries. Using the hospital data system, 5145 patients were screened and 4803 elected not to follow the inclusion criteria. Out of 342 included patients, 177 patients underwent PCI and 165 patients were referred for CABG. Patients with whom CABG was performed were significantly older (64.69±8.8 vs. 62.6±9.4, p=0.03), more often on insulin treatment (91/165=55.2% vs. 26/177=14.7%, p<0.01), had more complex anatomical characteristics i.e. higher SYNTAX scores (32.5 IQR (15) vs. 18.0 IQR (15), p<0.01) and with left main stenosis (70/165=42.4% vs. 7/177=4.0%, p<0.01), compared to patients treated with PCI. The cumulative incidence rates of all-cause death were significantly different between PCI and CABG at 4 years (16/177=9.0% vs. 26/165=15.7%, respectively, log-rank p=0.03). There was a higher incidence of all-cause mortality in PCI patients with intermediate (23–32) and high (≥33) SYNTAX scores compared with those with low (0–22) SYNTAX scores (6/32=18.8% vs. 6/124=4.8%, log-rank p=0.01; 4/21=19.1% vs. 6/124=4.8%, log-rank p=0.02, respectively). On the contrary, patients who underwent CABG displayed similar morality rates irrespective of the SYNTAX scores (SYNTAX 0–22: 5/34=14.7%; SYNTAX 23–32: 9/54=16.7%; SYNTAX ≥33: 12/77=15.6%; log-rank p=0.9). Finally, when compared with CABG, more deaths were observed following PCI with intermediate and high SYNTAX scores (intermediate SYNTAX (23–32) PCI: 6/32=18.8% vs. CABG: 26/165=15.8%, log-rank p=0.94; high SYNTAX (≥33) PCI: 4/21=19.1% vs. CABG 26/165=15.8%, log-rank p=0.87). During a 4-year follow-up, CABG in comparison with PCI was associated with a higher rate of all-cause death, which can be accounted for by older age and comorbidities. In diabetics, our analysis is suggestive that PCI probably should be avoided in patients with SYNTAX ≥23, which is in concordance with the most recent guidelines. Individualized risk assessment as well as quantification of CAD by SYNTAX score remains essential in choosing appropriate revascularization method in patients with diabetes and complex CAD. None