Impact of bivalirudin therapy in high-risk patients with acute myocardial infarction: 1-year results from the HORIZONS-AMI (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction) trial.

Objectives: This study sought to assess the relationship between 1-year mortality and baseline patient risk in the HORIZONS-AMI (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction) trial.

Background: The HORIZONS-AMI trial showed that bivalirudin compared with unfractionated heparin (UFH) plus glycoprotein IIb/IIIa inhibitors (GPI) decreased major bleeding and 30-day and 1-year mortality in patients undergoing primary percutaneous intervention for acute myocardial infarction.

Methods: Patients in the HORIZONS-AMI trial were classified as low, intermediate, and high risk according to the CADILLAC (Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications) risk score based on 7 clinical variables.

Results: Among 2,530 CADILLAC-score evaluable HORIZONS-AMI trial patients, 1,522 (60%) were classified as low risk, 531 (21%) as intermediate risk, and 477 (19%) as high risk. The mortality rates in the bivalirudin and UFH plus GPI arms, respectively, were 0.4% and 1.2% (p = 0.09) in the low-risk group, 4.2% and 4.1% (p = 0.99) in the intermediate-risk group, and 8.4% and 15.9% (p = 0.01) in the high-risk group. Among high-risk patients, there was also a decreased rate of recurrent myocardial infarction in patients randomized to bivalirudin as compared to UFH plus GPI (3.6% vs. 7.9%, p = 0.04).

Conclusions: In high-risk patients undergoing primary percutaneous coronary intervention for acute myocardial infarction, bivalirudin compared with UFH plus GPI reduces 1-year mortality and recurrent myocardial infarction. (HORIZONS-AMI trial; NCT00433966).