Positive predictive value of clinically suspected ST-segment elevation myocardial infarction using angiographic verification

Fibrinolysis has not been used for the treatment of ST-segment elevation myocardial infarction (STEMI) in Denmark since 2005. We aimed to assess the positive predictive value of clinically suspected STEMI among consecutive patients in a real-world setting where all patients with suspected STEMI undergo acute coronary angiography. We evaluated the clinical diagnosis of consecutive patients with suspected STEMI admitted to Aarhus University Hospital between September 1, 2010, and August 31, 2011. Conclusive STEMI was defined as a patient with an identifiable culprit lesion by angiography. Of 615 patients with suspected STEMI, 483 (79%) had conclusive STEMI, and 132 (21%) did not have an identifiable culprit lesion. A higher proportion of patients with conclusive STEMI were men, whereas patients without conclusive STEMI were more likely to have diabetes mellitus (16% vs 10%; p = 0.04), left bundle branch block (24% vs 2%; p <0.001), hypertension (48% vs 36%; p = 0.01), or a history of coronary artery bypass surgery (8% vs 2%; p = 0.001). Compared with the overall 79% with conclusive STEMI, patients with left bundle branch block or a history of coronary artery bypass surgery had positive predictive values of only 26% and 41%, respectively. Our findings thus indicate that a substantial number of patients would have received fibrinolysis, without any potential benefit but with the inherent risk of bleeding complications, if acute angiography had not been an option.