Abstract 2008: Impact of Hyperglycemia on Myocardial Damage and its Prognostic Implications in Patients with Acute ST-Segment Elevation Myocardial Infarction (STEMI) Assessed by Contrast-Enhanced Cardiac Magnetic Resonance Imaging (CMR)
To investigate the impact of admission glucose levels on myocardial damage and long term outcome in patients with acute STEMI using contrast-enhanced CMR. 130 consecutive patients (104 males; mean age 59.4±11.8 years) with first reperfused STEMI were included. Hyperglycemia was defined as glucose levels above 7.8mmol/l. CMR was performed within 3.9±2.2 days after admission on a 1.5 Tesla MR System. The imaging protocol included SSFP cine sequences for the calculation of LV function, volumes and mass. Total no reflow volumes (NRV) and delayed enhancement volumes (DEV) were calculated from planimetry of the IR-SSFP stacks of short axis images by disc-summation performed early / late following administration of 0.2mmol/kg/BW of gadodiamid. NRV and DEV were expressed as percent of LV Mass (NR%, DE%). Continuous variables were compared by Mann-Whitney test. Correlation of admission hyperglycemia and NR% was tested by spearman rank test. Patients were prospectively followed for 30±9 months. A stepwise logistic regression model was used to analyze the impact of hyperglycemia and CMR parameters on NR% and outcome. 55 of 130 (42%) patients had hyperglycemia on admission. Patients with admission hyperglycemia had lower LV ejection fraction (38.6±12.9% vs. 47.7±11.9%, p=0.001), greater ESV (89.2±39.2ml vs. 71.7±34.1ml, p=0.002), greater LV Mass (156.7±40.4g vs. 136.3±36.7g, p=0.003), larger DE% (19.3±13.8% vs. 9.7±8.5%, p<0.001) and larger NR% (8.1± 9.2% vs. 2.3± 4.2%, p<0.001). Admission hyperglycemia correlated moderate but significant to DE% (r=0.386, p<0.001) and NR% (r=0.421, p<0.001). In a multivariable logistic regression model admission hyperglycemia was an independent predictor (OR 6.8; CI 2.8 −16.6) of extensive (> median) microvascular obstruction, extensive delayed enhancement (OR 3.2; CI 1.5–7.1) and was associated with an increased risk for death and reinfarction (OR 4.7; CI 1.2–18.3) during follow up. Admission hyperglycemia in acute, reperfused STEMI is independently related to the extent of microvascular obstruction on early contrast-enhanced CMR and is associated with worse long-term outcome. Thus, CMR may play a major role in monitoring effects of glucose control on myocardial damage in AMI.