Researchers have found that the blood-thinning drug Lovenox works as well as a standard artery-clearing drug in patients with severe heart-related chest pain, but neither reduced the risk of death after a year of treatment.

The study, funded by drug company Aventis Pharmaceuticals which makes Lovenox, involved nearly 10,000 patients at 487 hospitals in 12 countries who suffered from acute coronary syndromes such as severe angina that cannot be treated with surgery or angioplasty.

The patients had all undergone revascularization, a treatment in which small holes are laser-drilled in the heart tissue to improve blood flow.

In the study, which was over a year, the patients were treated with either enoxaparin, the generic name for Lovenox, or a form of heparin, the standard medicine used in many hospitals for artery-clearing.

According to the report from the Duke Clinical Research Institute, in Durham, North Carolina, after one year the death rates in the two treatment groups were similar.

The researchers concluded that high-risk patients with acute coronary syndromes remain susceptible to continued cardiac events despite aggressive therapies.

The report is published in the current edition of the Journal of the American Medical Association.