Vial of heparin
A new study suggests bivalirudin does not produce better outcomes than heparin in patients undergoing transradial primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI).
Researchers found no significant difference in the rate of a composite of death, myocardial infarction, and stroke in patients who received bivalirudin or heparin, with or without glycoprotein (GP) IIb/IIIa inhibitors.
Likewise, the incidence of bleeding was not significantly different between the heparin and bivalirudin groups.
However, the rate of stent thrombosis was significantly higher in patients who received bivalirudin.
Ion S. Jovin, MD, of Virginia Commonwealth University in Richmond, and colleagues reported these results in JACC: Cardiovascular Interventions.
Using data from the National Cardiovascular Data Registry CathPCI Registry, the researchers examined the records of 67,368 patients with STEMI. The patients underwent primary PCI via radial access at 1584 sites between 2009 to 2015.
Patients received anticoagulation with bivalirudin (n=29,660) or heparin (n=37,708). Twenty-three percent (n=6781) of patients on bivalirudin received GP IIb/IIIa inhibitors, as did 59% of patients on heparin (n=22,416).
Results
In an unadjusted analysis, the researchers found no significant difference in the rate of the composite endpoint, which included death, myocardial infarction, and stroke. The incidence was 4.6% with bivalirudin and 4.7% with heparin (P=0.47).
However, patients who received bivalirudin had a significantly higher rate of acute stent thrombosis—1.03%—than patients who received heparin—0.602% (P<0.001).
And there were significantly fewer bleeding episodes with bivalirudin than with heparin—6.8% and 8.1%, respectively, (P<0.001).
The researchers adjusted their analysis for multiple variables, including a propensity score reflecting the probability of receiving bivalirudin to account for patient differences between groups.
After these adjustments, the odds ratio (OR) of the composite endpoint for bivalirudin versus heparin was 0.95 (P=0.152).
The OR ratio for acute stent thrombosis was 2.11 (P<0.001), and the OR for bleeding was 0.98 (P=0.57).
The researchers did note that, among patients who were not receiving GP IIb/IIIa inhibitors, outcomes were better in patients who received bivalirudin. They had a significantly lower risk of bleeding and the composite endpoint than patients who received heparin.
“Our sensitivity analysis provides some insights into direct comparisons of bivalirudin and heparin when GPIIb/IIIa inhibitors are forced out of the equation and suggests that, in the direct comparison, bivalirudin may have superior outcomes,” Dr Jovin said.
“However, our study showed that, in the real world, over a third of the patients with STEMI undergoing transradial PCI who receive heparin and about a fifth of patients who receive bivalirudin also receive GPIIb/IIIa inhibitors.”
The researchers suggested a need for a randomized trial in patients treated exclusively via transradial primary PCI and anticoagulated with bivalirudin versus heparin as well as a cost-effectiveness analysis comparing heparin and bivalirudin.
