ApPropRiateness - Stanetic of myOcardial revascUlarization assessed by SYNTAX Scores in patients with type 2 diabetes melliTus: the PROUST study*

Introduction
Results of currently available trials have shown divergent outcomes in diabetic patients undergoing percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Current guidelines do not recommend PCI in patients with diabetes and a SYNTAX score ≥ 23.

Aim
To compare all-cause 4-year mortality after revascularization for complex coronary artery disease (CAD) in diabetics.

Material and methods
The study group comprised consecutive patients with three-vessel CAD 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.

Results
Out of 342 diabetics, 177 patients underwent PCI and 165 patients were referred for CABG. The incidence of all-cause death was different between diabetics treated with PCI or CABG at 4 years (16/177, 9.0% vs. 26/165, 15.8%, respectively, p = 0.03). The difference was not evident in non-diabetics (PCI: 41/450, 9.1% vs. CABG: 19/249, 7.6%, p = 0.173). In diabetics, there was a higher incidence of all-cause mortality in PCI patients with intermediate-high (≥ 23) SYNTAX scores compared with those with low (0–22) SYNTAX scores (10/56, 17.9% vs. 6/121, 5.0%, respectively, p < 0.01). On the other hand, diabetics who underwent CABG showed similar mortality rates irrespective of the SYNTAX scores (SYNTAX 0–22: 3/29, 10.3%; SYNTAX ≥ 23: 23/136, 11.9%, p = 0.46). In the subgroup analysis, there was no interaction according to presence or absence of left main CAD (p for interaction = 0.12) as well as according to diabetes status (p for interaction = 0.38), whereas gender and SYNTAX scores were differentiators between PCI and CABG with a p for interaction < 0.1.

Conclusions
Our analysis supports recent evidence that diabetes is not a differentiator between PCI and CABG.