Depression or anxiety can increase your risk of heart disease, or dying from the disease if you already have it.
In one study, people were asked whether they had felt so sad, discouraged, or hopeless during the past month that they had wondered if anything was worthwhile. Those who answered yes had more than double the risk for coronary artery disease. Other studies suggest that chronic anxiety can increase the risk for sudden cardiac death.
Depression and anxiety are highly treatable with psychotherapy and medication. The most important step is to seek treatment when you think you might need it.