Bivalirudin? Heparin? Physicians Are Divided Over Antithrombotic Choices for PCI in STEMI, Survey Shows

Interventional cardiologists in the United States vary widely in their antithrombotic therapy preferences for primary PCI patients, according to new survey data.

In a nine-question survey sent to interventional cardiologists who were members of the Society for Cardiovascular Angiography and Interventions, Harsh Golwala, MD (University of Louisville School of Medicine, KY), and colleagues found that while more than half (53%) of the 393 respondents prefer to use bivalirudin with bailout glycoprotein IIb/IIIa inhibitor (GPI) for STEMI patients undergoing primary PCI, 32% primarily turn to heparin with bailout GPI and 15% prefer heparin with routine GPI.

“Despite however many trials and meta-analyses there are, I think that translation of those data streams into clinical practice remains problematic,” senior study author Ajay Kirtane, MD, SM (Columbia University Medical Center, New York), told TCTMD. “While some would argue that this is just an example of doctors doing whatever they think is right, I think the more mature way of looking at this is that clinical medicine is never a perfect science. No matter how many trials that get conducted, they don’t fully resolve the fundamental questions that clinicians are struggling with.”

Just under half of physicians surveyed said their choice of antithrombotic is unaffected by patient bleeding risk. However, access site seemed to weigh more heavily on their decision-making: 48% preferred bivalirudin for both radial and femoral access, 36% favored unfractionated heparin for radial and femoral access, and 15% preferred heparin for radial access and bivalirudin for femoral access.

There was also marked variability in dosing preferences regardless of antithrombotic strategy. More than half of respondents said they prefer a dose of 70 U/kg of unfractionated heparin with subsequent boluses based on activated clotting time, while 18% preferred doses of 70-100 U/kg with subsequent boluses. As for bivalirudin, 36% said they would stop administration at the end of the procedure, 34% said they would stop after the initial infusion bag ran out, and 21% preferred to continue with a prolonged infusion for up to 2 hours post-procedure.

Bivalirudin has been previously criticized for costing substantially more than heparin, but fewer than half of survey respondents (39%) reported that cost affected their choices. Clinical trial data were cited as a driving factor by 43% of physicians, who admitted to changing their preferences after reviewing recent study findings.

The study was published in the September 2016 issue of the Journal of Invasive Cardiology.

Not a Total Surprise

Kirtane said the variability observed in the survey responses wasn’t totally surprising given the wide range of clinical trial data presented within the last year or two. Also, even though the debate between physicians about bivalirudin versus heparin has been heated in the past, some of that has “died down” lately, he said.

The responses to how cost influences physician choices are notable, according to Kirtane. He believes that physicians should not think about cost “unless there’s some egregious difference” but conceded that others looking from a population health standpoint might disagree. Also, it’s likely that some physicians are factoring costs into their decision-making “if there is some question as to the degree with which one agent is that much better than another,” he said.

The implications of this survey reach further than simple anticoagulation decisions, Kirtane argued. Specifically, in modern cardiology “we have so many therapies that are pretty effective, [so] the degree with which we’re able to demonstrate significant incremental gains is limited,” he said. “When we start talking about pharmacological therapeutics and numbers needed to treat, we are getting into realms where it becomes harder to show demonstrable differences.”

Note: Kirtane is a faculty member of the Cardiovascular Research Foundation, the publisher of TCTMD.

Related Stories:

• Label Update for Bivalirudin Warns of Acute Stent Thrombosis With PCI for STEMI, Recommends Continued Infusion
• Meta-analysis Delves Into Bivalirudin Versus Heparin Debate in Primary PCI
• MATRIX Antithrombin: Bivalirudin Fails to Reduce Net Adverse Events vs Heparin in ACS Patients Undergoing PCI