CLINICAL CASES

Atrial Fibrillation Case Study #2 An 81-year-old white female with a history of chronic, non-valvular AF, a history of a previous ischemic stroke, and a history of mild congestive heart failure has been on a combination of clopidogrel and aspirin therapy because she was found to be intolerant of warfarin. She is on a proton pump blocker, an ACE inhibitor, a diuretic, and digoxin. She is admitted to the hospital for a GI bleed, and is found to have a hematocrit of 29 and a hemoglobin of 9.8. The aspirin and clopidogrel are discontinued.

Atrial Fibrillation Case Study #2 The patient stabilizes, and the cardiologist is consulted to determine the subsequent course of her antithrombotic treatment. She has a HAS-BLED score of 3. It is your opinion that:   Because of the documented GI bleed, the patient should not be treated with antithrombotic agents, because the risk of bleeding outweighs the risk of stroke and its complications. Because of the patient's risk profile, there should be an attempt to provide thromboprophylaxis against embolic stroke.

Atrial Fibrillation Case Study #2 The cardiologist has determined that this patient requires antithrombotic management for stroke prevention. At this point you would most likely:   Try the patient on warfarin again Try to re-introduce clopidogrel and aspirin Treat the patient with aspirin alone Introduce a non-monitored oral anticoagulant to the patient's regimen.  

Atrial Fibrillation Case Study #3 An 82-year-old man with hypertension and diabetes has permanent atrial fibrillation. He has a history of spinal stenosis and walks with a walker and has a history of falls. He has a CHADS-VASc score of 3, and a HAS— BLED score of 2. Which regimen would you prescribe for prophylaxis against thromboembolism?

Atrial Fibrillation Case Study #3 Which regimen would you prescribe for prophylaxis against thromboembolism? Warfarin (INR 2.0-3.0) Warfarin (INR 1.5-2.0) Aspirin 81 mg daily Aspirin 81 mg + clopidogrel 75 mg daily An oral Factor Xa or direct thrombin inhibitor

Atrial Fibrillation Case Study Anticoagulation in Patients at Risk of Falls “…persons taking warfarin must fall about 295 (535/1.81) times in 1 year for warfarin not to be the optimal therapy…”

Atrial Fibrillation Case Study #4 A 71-year-old man with AF, heart failure, and a prior history of stroke presents with unstable angina and proceeds to cardiac catheterization where a culprit lesion is identified. Optimal management includes: Placement of a drug-eluting stent with plan to continue anticoagulation in addition to 1 year of dual antiplatelet therapy Placement of a drug-eluting stent with 1 year of dual antiplatelet therapy alone Placement of a bare metal stent with plan to continue anticoagulation in addition to 1 month of dual antiplatelet therapy Placement of a bare metal stent with 1 month of dual antiplatelet therapy alone

Atrial Fibrillation Case Study #5 A 67-year-old female with a history of mitral stenosis with subsequent mechanical mitral valve replacement has AF. Which of the following anticoagulants can be used for stroke prevention in this patient? Warfarin Dabigatran Apixaban Rivaroxaban All of the above

Knowledge Assessment Question Atrial Fibrillation Knowledge Assessment Question The major potential benefits of the new non-monitored oral anticoagulants include: Rapid therapeutic anticoagulant effect Greater safety with regards to intracranial hemorrhage Proven reversal agent All of the above Both 1 and 2

Atrial Fibrillation Case Study #6 An 82-year-old man with AF has had several admissions over the past 6 months for heart failure complicated by worsening renal function. His creatinine clearance is currently 20 mL/min but frequently fluctuates to 10-15 mL/min. He has a HAS-BLED score of 3. The best anticoagulant regimen for stroke prevention is: Dabigatran 150 mg twice daily Dabigatran 75 mg twice daily Warfarin titrated to goal INR 2-3 Rivaroxaban 20 mg once daily Rivaroxaban 15 mg once daily

Atrial Fibrillation Case Study #7 A 79-year-old woman with a CHADS-VASc score of 2 who has been on warfarin for the past 2 years returns to clinic for routine follow-up. Her INR control has been excellent and she has never experienced a stroke or had significant bleeding. Her HAS-BLED score is 2. Her complaints today are thinning hair, cold intolerance, and fatigue. Her laboratory work is normal including a TSH.

Atrial Fibrillation Case Study #7 Which of her symptoms could be due to warfarin? Thinning hair Cold intolerance Fatigue Both 1 and 2 All of the above

Atrial Fibrillation Case Study #8 A 69-year-old woman with AF and CHADS2 score of 4 has a creatinine clearance that is stable at 40 mL/min. Which of the following anticoagulation regimens are suitable for her? Dabigatran 150 mg twice daily Dabigatran 75 mg twice daily Rivaroxaban 20 mg once daily Rivaroxaban 15 mg once daily Both 1 and 4

Atrial Fibrillation Case Study #8 What would her options be if her creatinine clearance was stable at 25 mL/min? Dabigatran 75 mg twice daily Rivaroxaban 15 mg once daily Only warfarin can be used in patients with creatinine clearance < 30 mL/min Both 1 and 2

Atrial Fibrillation Case Study #9 A 74-year-old man with AF on dabigatran is involved in a motor vehicle accident and needs emergency surgery. It is unclear if he is taking this medication but the surgeon is concerned about operating on him if he is fully anticoagulated.

Atrial Fibrillation Case Study #9 Which of the following lab tests, if normal, would reassure the team that the patient is not anticoagulated? INR (international normalized ratio) aPTT (activated partial thromboplastin time) PT (prothrombin time) Bleeding time

Atrial Fibrillation Case Study #10 A 60-year-old man with AF has been on warfarin but it has been very difficult to control his INR. You have decided to switch to dabigatran. Which of the following is true regarding transitioning a patient from warfarin to dagibatran? Start dabigatran when his INR < 3 Start dabigatran when his INR < 2 Start dabigatran 24 hours after his last dose of warfarin

Atrial Fibrillation Case Study #10 What if you decided to switch the patient to rivaroxaban? Start rivaroxaban when his INR < 3 Start rivaroxaban when his INR < 2 Start rivaroxaban 24 hours after his last dose of warfarin  

Atrial Fibrillation Case Study #11 A 78-year-old female with AF, systolic heart failure, hypertension, diabetes, and a history of significant GI bleeding has been on warfarin for many years but has had a difficult time controlling her INR with frequent supertherapeutic values despite intensive monitoring and titration of her warfarin dose. Her HAS-BLED score is 3. The best treatment option for her is: No antithrombotic therapy Discontinue warfarin and start aspirin Discontinue warfarin and start dabigatran Discontinue warfarin and start rivaroxaban Discontinue warfarin and start apixaban

Atrial Fibrillation Case Study #12 A 76-year-old woman with heart failure, hypertension, diabetes, and declining renal function (creatinine clearance 35 mL/min) has an embolic stroke due to newly diagnosed AF. She refuses to take warfarin. What is the best validated antithrombotic regimen in this particular patient? Aspirin Aspirin and clopidogrel Dabigatran Apixaban Rivaroxaban

Atrial Fibrillation Case Study #13 A 68-year-old man with a mechanical mitral valve develops AF. The best anticoagulant option for him is: Warfarin Dabigatran Apixaban Rivaroxaban Aspirin

Atrial Fibrillation Case Study #14 A 76-year-old man with heart failure and hypertension undergoes successful catheter ablation for symptomatic AF. Which of the following is true regarding his anticoagulation management? He no longer requires anticoagulation now that he is in sinus rhythm Patient should be on both aspirin and an anticoagulant Patient should be on an anticoagulant alone Aspirin and clopidogrel together is as effective as anticoagulation in these patients

Atrial Fibrillation Case Study #14 The cardiologist has determined that this patient requires antithrombotic management for stroke prevention. At this point you would most likely:   Try the patient on warfarin again Treat the patient with aspirin alone Introduce the non-monitored oral anticoagulant, apixaban, into the patient's regimen Introduce dabigatran into the patient’s regimen Introduce rivaroxaban into the patient’s regimen

Atrial Fibrillation Case Study #15 A 75-year-old male with a history of chronic, non-valvular AF, diabetic renal disease, previous history of ischemic stroke, history of mild HF, and controlled hypertension has been on warfarin therapy. The HAS-BLED score is 4. For the past 6 months, despite repeated visits for monitoring and warfarin dose adjustment, his INR has varied between 1.5 and 4.3. His estimated GFR is 30 mL/min.

Atrial Fibrillation Case Study #15 At this point you would:   Continue to try to stabilize his INR on warfarin Change to aspirin alone Introduce the non-monitored oral anticoagulant rivaroxaban into the patient's regimen Introduce the non-monitored oral anticoagulant apixaban into the patient's regimen Introduce the non-monitored oral anticoagulant dabigatran into the patient's regimen

Atrial Fibrillation Case Study #17 An 82-year-old man with hypertension, diabetes, mild congestive heart failure, and previous ischemic stroke, is diagnosed with atrial fibrillation. He has not been taking any anticoagulants.

Atrial Fibrillation Case Study #17 Which regimen would you initiate for prophylaxis against stroke? Warfarin (INR 2.0-3.0) Aspirin 81 mg + clopidogrel 75 mg daily Rivaroxaban Apixaban Dabigatran

Atrial Fibrillation Case Study #18 An 82-year-old man with hypertension, diabetes, mild CHF, and a previous ischemic stroke has permanent atrial fibrillation. He has been on warfarin for about 5 years and his INR has remained constant between 2.3 and 2.7. He has a HAS-BLED score of 3.

Atrial Fibrillation Case Study #18 Which regimen would you continue or switch to for prophylaxis against stroke? Continue current therapy with warfarin Aspirin 81 mg + clopidogrel 75 mg daily Rivaroxaban Apixaban Dabigatran

Atrial Fibrillation Case Study #19 A 75-year-old man with a CHADS2 of 3 has been taking dabigatran 150 mg for SPAF. His estimated GFR was 55 mL/min 6 months ago and is now 40 mL/min. I would now: Continue to monitor patient Switch patient to 75 mg dabigatran twice per day Switch patient to warfarin Switch patient to rivaroxaban Start ASA and clopidogrel