Apixaban plus P2Y12 inhibitor likely best for AF after ACS or PCI

Reuters Health - 31/01/2022 - In patients with atrial fibrillation (AF) after acute coronary syndromes (ACS) and/or percutaneous intervention (PCI), antithrombotic therapy with apixaban plus a P2Y12 inhibitor without aspirin is likely best, regardless of bleeding risk, researchers say.

In the AUGUSTUS trial, "we showed that a regimen that includes apixaban plus a P2Y12 inhibitor like clopidogrel without aspirin is effective and the safest strategy for these patients," Dr. Renato Lopes of Duke University School of Medicine in Durham told Reuters Health by email.

"In the current analysis," he said, "we extended these results, demonstrating that this regimen provides the greatest benefit to patients, irrespective of their stroke and bleeding risks (and) can be effectively and safely used across the spectrum of risks, according to the CHADSVASC and HASBLED scores."

As reported in the Journal of the American College of Cardiology, Dr. Lopes and colleagues conducted a non-prespecified post hoc analysis of the safety and efficacy of antithrombotic regimens according to HAS-BLED and CHA2DS2-VASc scores in AUGUSTUS participants with AF and ACS and/or PCI. (https://bit.ly/3soS4Mb)

The primary endpoint was major or clinically relevant nonmajor bleeding over six months of follow-up.

Of 4,386 patients with calculable scores (overall, mean age, 71; 30%, women; 93%, white) 66.8% had a HAS-BLED score of 3 or more and 81.7% had a CHA2DS2-VASc of 3 or more.

Bleeding rates were lower with apixaban than with a vitamin K antagonist (VKA), regardless of baseline risk: HR, 0.57 for HAS-BLED 2 or less; HR, 0.72 for HAS-BLED 3 or more.

Aspirin increased bleeding irrespective of baseline risk: HR, 1.86 for HAS-BLED 2; HR, 1.81 for HAS-BLED 3 or more.

Apixaban led to a lower risk of death or hospitalization than VKA, without a significant interaction with baseline stroke risk: HR, 0.92 for a CHA2DS2-VASc score of 2 or less; HR, 0.82 for a CHA2DS2-VASc of 3 or more.

Dr. Lopes said, "We plan to develop dedicated risk scores for this special population with AF and PCI so we can try to identify patients who are at high risk of stent thrombosis and who might benefit from triple therapy with aspirin, at least for some period of time after the PCI."

Dr. Pascal Vranckx of Jessa ziekenhuis in Hasselt, Belgium, coauthor of a related editorial, commented in an email to Reuters Health, "In the era of precision medicine, particularly in the setting of complex patients such as those (in the study), personalizing antithrombotic treatment regimens based on calibrated risk scores is an unmet need and warrants future investigation."

"Yet, the findings (of this study) must be considered in light of a number of considerations," he noted. "The CHA2DS2-VASC or the HAS-BLED risk scores were not developed to guide an antithrombotic regimen in patients with AF who underwent PCI or experienced an ACS. The use of a different score - i.e., the PRESISE-DAPT score, at a standard bleeding risk cut-off ≥25 - which weighed similar baseline covariates differently in similar populations, led to different conclusions."

"Bleeding and thrombotic complications overlap," he said. "When both ischemic and bleeding risk factors are present, the risk factors for bleeding emerged as most impactful on decision making regarding DAPT duration among patients without an indication for oral anticoagulants (OAC). In patients with AF undergoing PCI, OAC treatment by itself, may already be considered a major bleeding risk!"

"The Academic Research Consortium High Bleeding Risk consensus criteria may be valuable to further stratify and individualize bleeding risks," he said. "In validation studies, with incremental risk criteria, beyond OAC use, a further increase in bleeding risk is noted."

"Categorizing a patient as having high bleeding risk is challenged by the notion that the risk for bleeding is dynamic by nature and might change over time," he added. "In general, risk scores based on baseline variables, even when useful to improve the accuracy of the prognostic assumptions affecting clinical decisions, cannot be considered a clear-cut decision rule or a substitute for case-by-case critical judgment."

The AUGUSTUS trial and the study were supported by Bristol Myers Squibb and Pfizer. Dr. Lopes and many coauthors have received fees from the company. Dr. Vranckx has also received fees from Bristol Myers Squibb.

SOURCE: https://bit.ly/3L0Powm and https://bit.ly/3IMUhqY Journal of the American College of Cardiology, online January 31, 2022.

By Marilynn Larkin

© 2023 The Author(s). Published by Medicom Medical Publishers.
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Posted on 31 January, 20228 February, 2022