Bad Temper? You May Be at Higher Risk of Heart Attack After angry outbursts, risk of heart attack, stroke increase: study By Evann Gastaldo, Newser Staff Posted Mar 5, 2014 2:00 PM CST 15 comments Comments (Shutterstock) (Newser) – Angry? You may want to calm down, or you could put yourself at higher risk of a heart attack or stroke, a new study finds. Researchers found that there's a two-hour "danger zone" following an outburst of rage during which people are nearly five times more likely to have a heart attack and more than three times more likely to have a stroke, the BBC reports. Risk of an irregular heartbeat also increased, CBS News reports. And the risk is cumulative—so the more often you lose your temper, the higher your risk may be. It's not clear why anger might be a trigger for heart attacks and strokes (the study did not actually establish cause and effect), though experts know that chronic stress can contribute to heart disease. "Anger causes our heart rate to increase through the sympathetic nervous system and causes our stress hormones to become elevated (the fight or flight mechanism)," says one expert, according to CNN. "We breathe faster, all of which may trigger undesirable reactions in our blood pressure or in our arteries," such as the heart or brain not getting the blood and oxygen they need.