Effect of diabetes mellitus on periprocedural myocardial infarction in patients undergoing coronary stent implantation

Background: Diabetic patients undergoing percutaneous coronary interventions are still regarded as a very high risk category because of an increased platelet reactivity and risk of complications, especially in patients with inadequate glycaemic control. However, although its prognostic effect on long-term outcome is well-defined, still unclear is the effect of diabetes on the risk of periprocedural myocardial infarction in patients undergoing percutaneous coronary interventions, which was therefore the aim of our study. Methods: Myonecrosis biomarkers were dosed at intervals from 6 to 48 h after nonemergent percutaneous coronary interventions. Periprocedural myocardial infarction was defined as creatine kinase-MB increase by three times the upper limit normal or by 50% of an elevated baseline value, whereas periprocedural myonecrosis as troponin I increase by three times the upper limit normal or 50% of baseline. Results: Of 1311 patients, diabetes mellitus was found in 458 patients (34.9%) and associated with age (p=0.03), hypertension (p<0.001), renal failure (p=0.01), previous MI (p=0.03), previous coronary revascularization (p<0.001), higher fasting glycaemia and lower haemoglobin (p<0.001), more severe coronary disease (p<0.001), multivessel percutaneous coronary interventions (p=0.03), coronary calcification (p=0.003) and in-stent restenosis (p<0.001) but lower presence of thrombus (p=0.03). Diabetic patients were receiving significantly more frequent specific pharmacological treatment at admission. Diabetic status did not influence the risk of periprocedural myocardial infarction or periprocedural myonecrosis [adjusted OR(95%CI)=0.90(0.64-1.27), p=0.57 and adjusted OR(95%CI)=0.92(0.70-1.21), p=0.55]. Amongst diabetic patients, we did not observe any effect of chronic glycaemic control on periprocedural myocardial infarction. Conclusions: Diabetic status, independent of chronic glycaemic control, is not associated with increased risk of periprocedural myocardial infarction and myonecrosis in patients undergoing percutaneous coronary interventions.