Results of a post-hoc subanalysis from the phase III ARISTOTLE trial have shown that stroke or systemic embolism and major bleeding were uncommon within 30 days in non-valvular atrial fibrillation patients who undertook a medical procedure. Data were reported at the European Cardiology Association (ESC) Congress (31 August – 4 September, Amsterdam, The Netherlands).
The results showed that in the 30-day period following a procedure, rates of clinical events (stroke or systemic embolism, major bleeding, and all-cause death) were comparable in the apixaban and warfarin treatment arms.
Among patients treated with apixaban, event rates in the 30-day period following a procedure were similar whether was stopped prior to the procedure or continued during the procedure. In patients taking warfarin, there was at least a twofold higher rate of major bleeding and death during the 30-day period following a procedure when warfarin was continued during the procedure compared to when warfarin was stopped prior to the procedure.
“For patients with non-valvular atrial fibrillation who undergo procedures, the rate of anticoagulation-related adverse events appears to be similar whether the patient is chronically anticoagulated with apixaban or warfarin,” said study lead investigator Renato Lopes of Duke University Medical Center in Durham, USA. “For non-valvular atrial fibrillation patients for whom interruption of anticoagulation for a procedure is required, these findings suggest that using apixaban instead of warfarin, which is more challenging to stop and restart, may simplify the management of peri-operative anticoagulation in non-valvular atrial fibrillation patients.”
There were 11,417 procedures in 6,162 patients from the 18,201 patients enrolled in the ARISTOTLE trial. The most common procedures were dental extraction/oral surgery, colonoscopy, upper endoscopy, and ophthalmic surgery. For 4,082 (35.8%) procedures, study drug was not stopped. In the 7,335 procedures (64.2%) where study drug was stopped, the median time of study drug stop was four days before the procedure for both apixaban and warfarin-treated patients. The procedures were classified as major if they required general anaesthesia, and procedures were also classified as emergent or non-emergent by investigators.
Among patients undergoing procedures in the ARISTOTLE trial, stroke and systemic embolism were uncommon and the 30-day post-procedure rates for these events were not statistically different in the two treatment arms (0.33% for apixaban vs. 0.53% for warfarin). Major bleeding occurred in a comparable number of patients 30 days post-procedure in the two treatment arms (1.57% for apixaban vs. 1.81% for warfarin). In patients taking apixaban, the rates of post-procedural stroke or systemic embolism and major bleeding were similar whether apixaban was interrupted or continued. In patients taking warfarin, the rates of post-procedure major bleeding and death appeared higher when warfarin was continued compared to when it was interrupted.
“The current results do not include analyses for individual procedure types and therefore decisions whether to interrupt apixaban or warfarin prior to procedures should be based on consideration of procedural bleeding risk and patient thrombotic risk,” said Lopes. “In addition, further analyses, including analyses according to type of procedures and timing, are ongoing to better define these relationships.”
The US Prescribing Information for apixaban states that apixaban should be discontinued at least 48 hours prior to elective surgery or invasive procedures with a moderate or high risk of unacceptable or clinically significant bleeding. Apixaban should be discontinued at least 24 hours prior to elective surgery or invasive procedures with a low risk of bleeding or where the bleeding would be noncritical in location and easily controlled.