Presentations of acute myocardial infarction (MI) can be divided into diagnostic subcategories that require different treatments. This article reports the results of a study that explored and compared patientsʼ perceptions of their illness and motivation for behavioural change after different treatments for MI. Results suggest that patients who have had non-ST elevation MI (NSTEMI) and whose initial diagnosis is uncertain take their condition less seriously than those who have had STEMI and invasive or ‘urgent’ treatments. This tendency can make them less motivated to change their lifestyles. Healthcare professionals in emergency departments should be aware of, and address, patientsʼ misconceptions and provide clear and consistent advice to improve their long-term outcomes.Lisa Dullaghan and colleagues discuss how patients with non-ST elevation myocardial infarction perceive their illness and the treatments they have received