OBJECTIVE Acute myocardial infarction is often accompanied by anxiety, but the effect of this emotion on recovery is unclear. The purpose of this study was to determine the association between patient anxiety early after acute myocardial infarction and the incidence of subsequent in-hospital complications. METHODS We assessed anxiety level within 48 hours of patient arrival at the hospital in 86 confirmed myocardial infarction patients. Anxiety was measured using the Brief Symptom Inventory. Myocardial infarction complications were defined as reinfarction, new onset ischemia, ventricular fibrillation, sustained ventricular tachycardia, or in-hospital death. RESULTS More complications were seen in patients with higher versus lower levels of anxiety (19.6% vs 6%; p = .001). Multiple logistic regression was used to control for those clinical and sociodemographic factors that can influence the incidence of complications and demonstrated that higher anxiety level was independently predictive of complications. Patients with higher anxiety levels were 4.9 times (p = .001) more likely to have subsequent complications. CONCLUSIONS Anxiety early after myocardial infarction onset is associated with increased risk of ischemic and arrhythmic complications. This finding suggests that anxiety should be considered among the conventional risk factors for in-hospital acute myocardial infarction complications.