The findings are based on a study of 2,755 male employees who had not had a heart attack at initial screening between 1992 and 1995 when the study began.
Participants were asked whether they used avoidance tactics, such as walking away from the situation or letting things pass without saying anything, and how often they did so.
They were also asked if they experienced any physical symptoms, such as headache as a result, and whether they instead vented their anger at home.
The researchers, led by Dr Constanze Leineweber from Stockholm University, found that up to 2003, 47 men had suffered a heart attack or died from ischaemic heart disease.
After adjusting for other risk factors, they found that men who persistently failed to openly express their anger were more than twice as likely to have a heart attack or die of serious heart disease as those who did show their anger.