Findings published July 5 in Lancet show low-dose heparin alone to be at least as effective and safe as bivalirudin alone when used in radial PCI in acute MI patients presenting with STEMI, if not more so.

The HEAT-PPCI (How Effective are Antithrombotic Therapies in Primary Percutaneous Coronary Intervention) trial enrolled 1,812 patients preparing to undergo PCI at the Liverpool Heart and Chest Hospital in the  U.K. between February 2012 and November 2013 and randomized them equally into two interventions, low-dose heparin or bivalirudin (Angiomax, The Medicines Company). A GP IIb/IIIa inhibitor was used for rescue purposes as needed.

Lead author Adeel Shahzad, MBBS, MRCP, and colleagues found that outcomes were largely similar between the two groups. Approximately 13 percent of all patients required rescue GB IIb/IIIa inhibitors. Of those who did, reasons included high intracoronary thrombus burden, complex lesion or stent placement, slow flow or perceived failure of antiplatelet loading.

Major adverse cardiac event rates were higher in the bivalirudin group, occurring in 8.7 percent of patients as opposed to 5.7 percent patients in the heparin group. This heparin advantage occurred across all individual outcomes, with the exception of minor bleeds and any bleeds.

Death occurred in 5.1 percent of bivalirudin patients as opposed to 4.3 percent of heparin patients. A significant difference was seen between bivalirudin and heparin in new MI/reinfarction (2.7 percent vs 0.9 percent) and unplanned target lesion revascularization (2.7 percent vs 0.7 percent).

This finding is important, both for patient outcomes and procedural cost, according to the writers of an accompanying editorial.

“HEAT-PPCI provides strong evidence that bivalirudin alone compared with 70 U/kg of heparin alone (with infrequent bailout use of GP IIb/IIIA inhibitors in both arms), with radial access for STEMI percutaneous coronary intervention, seems to be inferior to heparin as administered in this trial,” wrote Peter B. Berger, MD, and James C. Blankenship, MD, of Geisinger Health System, in Danville, Penn. “Even if heparin alone had produced statistically similar outcomes to bivalirudin, it would have been a win for heparin. A drug that costs less than a 400th of another that has similar efficacy and safety ought [to] be used preferentially.”