[Differences in the treatment of patients with type 1 and type 2 myocardial infarction. Guidelines for the treatment of type 2 myocardial infarction are completely missing].

To study the differences between type 2 and type 1 infarction (AMI) regarding background variables and treatment a retrospective study was performed. A total of 200 patients with AMI hospitalized at the University Hospital in Uppsala during 2011 were included in the study. Half of the group was patients registered in the SWEDEHEART registry and the other half was patients not registered. The AMI diagnoses were validated and all AMI patients classified into AMI subtypes 1-5 by two independent researchers in accordance with the Universal definition of MI from 2007. Type 2 AMI was much more common among patients not registered in SWEDEHEART versus those registered (31 vs. 11%). Type 2 AMI was associated with higher age, female sex and comorbidities such as heart failure, atrial fibrillation and chronic kidney disease. The most common underlying mechanisms causing type 2 AMI were tachycardia and anaemia. Compared with type 1 AMI, patients with type 2 AMI had a smaller infarct size, had coronary angiography less often performed and were less often put on standard secondary preventive treatment.