The aim of the present study was to explore the association between outbursts of anger and acute myocardial infarction (AMI) risk. Outbursts of anger are associated with an abrupt increase in cardiovascular events; however, it remains unknown whether greater levels of anger intensity are associated with greater levels of AMI risk or whether potentially modifiable factors can mitigate the short-term risk of AMI. We conducted a case-crossover analysis of 3,886 participants from the multicenter Determinants of Myocardial Infarction Onset Study, who were interviewed during the index hospitalization for AMI from 1989 to 1996. We compared the observed number and intensity of anger outbursts in the 2 hours preceding AMI symptom onset with its expected frequency according to each patient's control information, defined as the number of anger outbursts in the previous year. Of the 3,886 participants in the Determinants of Myocardial Infarction Onset Study, 1,484 (38%) reported outbursts of anger in the previous year. The incidence rate of AMI onset was elevated 2.43-fold (95% confidence interval 2.01 to 2.90) within 2 hours of an outburst of anger. The association was consistently stronger with increasing anger intensities (p trend <0.001). In conclusion, the risk of experiencing AMI was more than twofold greater after outbursts of anger compared with at other times, and greater intensities of anger were associated with greater relative risks. Compared with nonusers, regular β-blocker users had a lower susceptibility to heart attacks triggered by anger, suggesting that some drugs might lower the risk from each anger episode.