Up to 30% of patients with atrial fibrillation (AF) have coronary artery disease (CAD).
Many undergo percutaneous coronary intervention (PCI), requiring antithrombotic therapy
(ATT) with acetylsalicylic acid (ASA) and a P2Y12 inhibitor to prevent stent thrombosis,
combined with warfarin or a direct oral anticoagulant (DOAC) for stroke prevention
(triple therapy). In the setting of acute coronary syndrome (ACS) with PCI, or elective
PCI with high-risk features, Canadian AF guidelines recommend limiting ASA to 30 days
post-PCI, as continuation of triple therapy beyond 30 days results in increased bleeding
without reduction in ischemic outcomes. They also recommend 1-12 months of clopidogrel,
and oral anticoagulation with doses that may change through the 12 months post-PCI.
The complexity of these regimens may contribute to unintended modifications, increasing
the risk of thrombosis and/or bleeding. Our goal was to describe patient experiences
with combination ATT, including unplanned modifications, after discharge from acute
METHODS AND RESULTS
This is a prospective, observational study of patients with documented AF requiring
OAC, who underwent PCI and were discharged on combination ATT. Patients were contacted
at 1-, 3-, 6-, and 12-months post-PCI. Fifty-eight patients have been enrolled (January
2020-April 2021) with data from at least 1 time point available for 55 patients (Table
1). Of these, 31 (56.4%) experienced at least one unplanned modification to ATT and
15 (27.3%) experienced more than one. Forty-five (81.8%) of the 55 patients were discharged
with a plan for triple therapy. In 18 patients (40.0%), the original plan was to stop
ASA at 1-month post-PCI; 7 (38.9%) did not stop as directed. Nine patients (20.0%)
had ASA stopped prior to the intended stop date by a prescriber. Of the 31 patients
with at least one modification, 9 (29.0%) experienced a modification to clopidogrel
which was a prolonged duration in 5 patients; prescriber-driven in 2. Eighteen (58.1%)
patients experienced modifications related to oral anticoagulants; 4 in 10 (40.0%)
warfarin-treated patients and 14 in 45 (31.1%) DOAC-treated patients. Of all patients
with at least one modification, 15 (48.4%) experienced a bleeding event that was either
a reason for, or due to, an unplanned ATT modification.
More than 1 in 2 patients with AF undergoing PCI experienced an unplanned modification
to their ATT and half of those were associated with bleeding. This underscores the
challenges of managing combination ATT for patients and clinicians alike and emphasizes
the need for follow up and patient support after discharge.