Within a year after a heart attack, you're twice as likely to suffer severe depression, even if you've never had the problem before.
This, in turn, can increase your chances of angina, a new study has discovered. One in five heart attack patients will go on to suffer angina in the 12 months afterwards. Although depression is a major cause, researchers have discovered that many heart attack patients continue to smoke, which can also cause the angina.
(Source: Archives of Internal medicine, 2008; 168: 1310-16. http://archinte.ama-assn.org/cgi/content/short/168/12/1310)