The impact of infarct type on the reliability of early oral glucose tolerance testing in patients with myocardial infarction

Abstract Background Previously unknown glucose perturbations are common in patients with myocardial infarction (MI). We evaluated the accuracy of an early oral glucose tolerance test OGTT in relation to the extent of the MI. Material and methods An OGTT was performed in 134 patients with MI without known diabetes (DM) after 4–5days (predischarge) and 3months. The MI was classified as transmural (TMI; n =70) or subendocardial (SEMI; n =102). Results Predischarge TMI-patients had normal GT, impaired GT or DM in 31%, 33% and 36%. These proportions were 35%, 39% and 26% after 3months. The corresponding proportions in SEMI-patients were 35%, 35% and 30% and 35%, 40% and 25%. At admission and the first 2days fasting glucose was higher in TMI than SEMI-patients. Conclusion The outcome of an early OGTT is valid but the test should not be performed earlier than 4–5days after the event especially in patients with extensive infarctions.