Guidelines on triple therapy use in ACS need expansion
MedWire News: US researchers call for improved guidance on use of anticoagulation and dual antiplatelet agent regimens (triple therapy) in patients with acute coronary syndromes (ACS.
The team found patients with atrial fibrillation (AF) or atrial flutter were more likely to receive dual antiplatelet therapy plus warfarin than other individuals, but less than a fifth of AF or atrial flutter patients received this regimen.
“Efforts to define which patient should receive triple therapy are needed,” say Deepak Bhatt (Veterans Affairs Boston Healthcare System and Brigham and Women's Hospital, Boston, Massachusetts) and co-authors in the American Journal of Cardiology.
“As newer antithrombotic regimens are studied for ACS, it is important that clinical trials include patients taking oral anticoagulation and antiplatelet therapy to define more precisely the degree of benefit and risk.”
The team examined antithrombotic regimens in 86,304 ACS patients registered with the Get With The Guidelines Coronary Artery Disease national registry who were treated in the USA between 2004 and 2007.
The majority (70.4%) of patients received single antiplatelet therapy plus oral anticoagulation on discharge and 22.1% received a single antiplatelet agent alone, but 4.6% of patients were prescribed triple therapy, and 0.3% received only oral anticoagulation.
Over half (56.9%) of patients underwent percutaneous coronary intervention (PCI), 94.8% of whom received dual or triple therapy.
Analysis showed that patients with a history of AF, new-onset AF, or a history of atrial flutter were significantly more likely to receive triple therapy than those without, at odds ratios (ORs) of 7.01, 3.76, and 3.38, respectively.
In contrast, patients were significantly less likely to receive triple therapy if they had a history of stroke or a pacemaker, if they had ST-elevation myocardial infarction than stable angina, or if they had undergone PCI . Triple therapy was also negatively associated with anemia, greater ejection fraction, or discharge from hospitals in the Midwest, South or West compared with the Northeast.
However, the researchers note that although 7.9% of the patients had AF or atrial flutter that may require oral anticoagulation therapy, just 17.8% of these were prescribed triple therapy.
And while PCI with stenting was the strongest predictor of triple therapy in AF or flutter patients (OR=2.7), only 27.2% of patients who underwent PCI, with or without stenting, received triple therapy.
“Our study has highlighted the wide variability in discharge antithrombotic therapy in patients who might need concomitant oral anticoagulation after an ACS and/or PCI,” Bhatt et al conclude.
However, noting suggestions that antithrombotic therapy should be formally assessed by a patient’s risk for stroke and bleeding, the team cautions that “patients who have the greatest risk for bleeding often have the greatest risk for stroke.”
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By Lynda Williams