November 26, 2008 - Patients prescribed clopidogrel (Plavix) and other anti-clotting medications after undergoing interventional cardiology procedures should continue taking their medicines unless their cardiologist tells them to stop, despite conflicting data from two studies presented at the 2008 American Heart Association Scientific Sessions concerning possible interaction between clopidogrel and heartburn medication proton pump inhibitors (PPI; common brands include Prilosec, Prevacid and Nexium).
The studies do not provide sufficient evidence to change clinical practice, says The Society for Cardiovascular Angiography and Interventions (SCAI). Guidelines authored by SCAI and other cardiovascular organizations recommend dual antiplatelet therapy, typically clopidogrel plus aspirin, for no less that one year following implantation of stents, the tiny devices that keep arteries open following angioplasty procedures. Clinical trials have shown this drug regimen effectively prevents blood clots that can lead to rare but potentially life-threatening cardiac events.
“The key message for physicians is to follow the indications and the guidelines,” said Dr. Steven R. Bailey, SCAI president-elect. “All patients who have received a stent in the past year should be on dual antiplatelet therapy. And, if there is a good indication for specific patients to take one of the heartburn medications, then physicians should prescribe them. At this time, there is no compelling evidence to change clinical practice.”
In addition to clopidogrel and aspirin, physicians sometimes prescribe PPIs to take along with these medications after procedures such as angioplasty to lessen the possibility of gastric (stomach) bleeding. Two studies presented earlier this month came to opposite conclusions concerning adverse effects when patients take both clopidogrel and PPIs. The first study, a database analysis, found an increase in cardiac events in patients taking clopidogrel along with PPIs. The second study, called CREDO, found no adverse effect when clopidogrel was taken along with a PPI. Patients in this study who were taking a PPI had similar rates of adverse events whether they took clopidogrel or a placebo with a PPI.
Based on these conflicting findings and the previously published literature, SCAI recommends physicians continue prescribing dual antiplatelet therapy after stent implantation according to the guidelines and prescribe a PPI medication when there is a clinical indication for it.
SCAI is eager for the findings of ongoing studies, including the large, randomized study COGENT-1, which is expected to clarify the possible interactions between clopidogrel and PPIs.
“The medical community is actively engaged in a number of studies looking at how heartburn medications do or do not interact with clopidogrel and other antiplatelet medications,” said Dr. Paul Gurbel, SCAI member. “As we learn more, SCAI will review the guidelines and other clinical statements and keep them current with the data.”
For more information: www.scai.org