Case Study Highlights Risks for A-fib Patients Undergoing PCI in Absence of Evidence-Based Guidelines

In the absence of evidence-based guidelines, physicians need to pay close attention to preprocedural risk stratification and tailor drug therapy to individual patients, say the authors of a recently published case study of an A-fib patient on triple therapy who suffered bleeding complications following PCI.

Only 1 study—the randomized WOEST trial—has shown both an efficacy and a safety advantage for the combination of warfarin and clopidogrel vs triple therapy. But the sample size was small (n = 573), and only one-quarter of patients received PCI for ACS. Since then, registry studies have shown similar outcomes in real-world populations.

In a case study and discussion published online December 7, 2015, in Circulation: Cardiovascular Interventions, a team from the Montreal Heart Institute (Montreal, Canada) consisting of Fabien Picard, MD, MSc; Victor-Xavier Tadros, MD, MSc; and Anita W. Asgar, MD, describes a GI bleed in a 77-year-old woman with permanent A-fib 2 months after receiving PCI.

Given her CHA₂DS₂-VASc score of 4 and low bleeding risk, she was originally discharged on aspirin, clopidogrel, and warfarin for 6 months. But after the bleed—determined to be from a gastric ulcer—aspirin was discontinued and an oral proton pump inhibitor (PPI) was added. The patient was continued on dual therapy for 10 additional months and had no further complications.

Challenges of CHA₂DS₂-VASc

John C. Messenger, MD, of the University of Colorado School of Medicine (Aurora, CO), commenting on the case for TCTMD, said he would have also treated this patient with triple therapy because of her CHA₂DS₂-VASc score. But, he added, he would have originally discharged her on a PPI, according to current recommendations.

To prevent major bleeding events, Asgar says in the report, pretreatment with P2Y12 receptor antagonists should be withheld until the time of angiography and procedural details like radial access, smaller sheaths, and optimally deciding between DES and BMS can help. Also, antithrombotic therapy should be “tailored,” warfarin dose should be monitored, and routine PPI use is “highly recommended,” she advises.

“All of us have had patients come back with GI bleeding,” Messenger added. “It’s incumbent upon all of us to do a better job of doing preprocedural risk stratification for both stroke risk and bleeding risk, and optimize the treatment duration and the drugs used in the combination for each patient based on the limited data we have.”

The challenge, he said, is that simply being a woman gives her a CHA₂DS₂-VASc of 1. “How do you make decisions in someone whose only risk factor is them being a woman?” Messenger asked, adding that he would probably choose triple therapy “if they really had an indication,” but might consider dropping the oral anticoagulant for a period of time to avoid “overtreating.”

Patients with a CHA₂DS₂-VASc of 1 have a yearly stroke risk of between 1% and 1.5%, he reported, but their bleeding risk on triple therapy is “markedly higher.” Future studies should focus on ischemic and bleeding outcomes in patients who are at lower-bleeding risk to see whether their oral anticoagulant can be omitted for 6-12 months after stenting, Messenger said.

More Trials Coming, But Still No Complete Picture

Between 5% and 8% of patients receiving a stent are indicated for long-term oral anticoagulation, Asgar writes. While the top priority of a clinician is to prevent death and disability, “the challenge is finding the optimal balance between preventing thromboembolic events, such as thromboembolic stroke, without increasing bleeding risk post-PCI,” she says.

Doing so is hard, Messenger said, as “none of [the European Society of Cardiology recommendations] are based on evidence. It’s very frustrating when you try to talk to patients about what we know and what we don’t know.”

Moreover, Asgar thinks “actual guidelines are disparate and complex,” and the reluctance to change them is based on lack of randomized evidence and limitations of WOEST. Moreover, these patients are often so complex that an “individual patient-centered approach is preferred,” she adds.

Novel oral anticoagulants like prasugrel and ticagrelor are available, Asgar continues, but “their combination with antithrombotic therapy is not recommended and preference is generally given to use of clopidogrel.”

Multiple “beautifully designed randomized trials” are underway, Messenger notes—PIONEER AF-PCI, REDUAL-PCI, and AUGUSTUS—but all “conveniently” exclude the clopidogrel plus a vitamin K antagonist arm that did best in WOEST. “The rivaroxaban makers are keen to look at their drug, the apixaban folks want to look at apixaban, and the dabigatran people want to look at dabigatran,” he said, adding that science may never be able to provide the “right answer” about safety of generic medications.

 

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Source: 
Picard F, Tadros V-X, Asgar AW. Triple antithrombotic therapy in atrial fibrillation patients with an indication for oral anticoagulation undergoing percutaneous coronary intervention. Circ Cardiovasc Interv. 2015;8:e003217.

Disclosure:

• Asgar, Tadros, and Messenger report no relevant conflicts of interest.
• Picard reports receiving a grant from the French Federation of Cardiology.

Related Stories:

• ISAR-TRIPLE Published: No Net Gain for 6 Weeks vs 6 Months of Triple Therapy
• Triple Therapy Yields No Thrombotic Benefit, More Bleeding in Older PCI Patients With A-fib
• WOEST: Clopidogrel Alone Works Best for PCI Patients on Oral Anticoagulants