Compared with those on placebos, giving heparin to people who have heart conditions like unstable angina and some forms of heart attack reduces the risk of having another heart attack, concluded a Cochrane Systematic Review. However, heparin also increases the chance of suffering from minor bleeding. In each study the agents were given within 24 to 72 hours of the first symptoms, and were given for between two and eight days.

Taking heparin does not, however, decrease the overall risk of dying or reduce the chance of having further bouts of angina.

These conclusions were drawn after Cochrane Researchers considered the data within eight studies that included 3118 participants, comparing the effects of giving patients either heparin or a placebo.

Heparin effectively thins blood clotting by interfering with its clotting mechanism.

“Our research supports the use of heparins in the early treatment of acute coronary syndromes,” says lead researcher Dr Kirk Magee who works in the Department of Emergency Medicine at Dalhousie University in Halifax, Nova Scotia.