Direct oral anticoagulants safer than warfarin for AFib patients with bioprosthetic heart valves
Direct oral anticoagulants (DOACs) and warfarin are equally effective as a treatment option for atrial fibrillation (AFib) patients with bioprosthetic heart valves (BHVs), according to a new study published in the American Journal of Cardiology.
However, DOACs appear to be safer for patients than warfarin, resulting in fewer intracranial bleeds.
“The COVID-19 pandemic has brought additional consideration to the care of patients receiving warfarin therapy,” wrote first author Lewei Duan, MS, department of research and evaluation for Kaiser Permanente Southern California in Pasadena, and colleagues. “For patients receiving warfarin therapy, frequent blood draws for international normalized ratio monitoring may be difficult because of lockdowns. Switching patients from warfarin to DOACs is a potential strategy to minimize patients’ need to leave their homes.”
DOACs have been approved for use in nonvalvular AFib, the researchers noted, but a bit of uncertainty remains when it comes to using them to treat patients with valvular heart disease. The team hoped its analysis could provide some improved clarity.
Duan et al. explored data from more than 2,600 patients with AFib and a BHV who were treated at the same large integrated healthcare delivery system in California. The presence of a BHV was confirmed for each patient through a manual review. At least six months of follow-up data were available for each patient.
Overall, more than 2,200 patients were given warfarin and the remaining participants were all given a DOAC. Among DOAC patients, a majority (362) received dabigatran. Some patients also received apixaban or rivaroxaban.
The study’s primary effectiveness outcome was ischemic stroke, systemic embolism and transient ischemic attack; “no significant association” was observed between patients given DOACs and patients given warfarin. Both treatment options, in other words, were effective when it came to preventing these ischemic events.
The study’s primary safety outcome, on the other hand, was intracranial hemorrhage, gastrointestinal bleeding and other bleeding events. The use of DOACs was consistently associated with a lower risk of experiencing these outcomes than warfarin.
“Intracranial bleeding is the most serious bleeding complication since mortality and morbidity associated with intracranial bleed is much higher than other types of bleeding,” the authors wrote. “Our finding that DOACs were associated with lower rates of intracranial hemorrhage is consistent with results from the pivotal clinical trials.”
The team did note that their study included certain limitations. The use of over-the-counter medications such as aspirin could not be tracked, for example, and much more dabigatran was used to treat patients than the other DOACs. Also, since study participations were all insured, “the results do not generalize to patients without insurance.”
Even with those things in mind, however, the team concluded that their work supports the use of DOACs for AFib in patients with BHVs.
Read the full study here.
Michael has more than 18 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.