What should be the antiplatelet/anticoagulant strategy after hospital discharge for an elderly patient with ischemic dilated cardiomyopathy (IDC) and a history of ischemic stroke in the anterior inferior cerebellar area (AICA)?

Antiplatelet/Anticoagulant Strategy for Elderly Patient with Ischemic Dilated Cardiomyopathy and AICA Stroke

This patient requires oral anticoagulation with a direct oral anticoagulant (DOAC) as the primary antithrombotic strategy, given the high thromboembolic risk from ischemic cardiomyopathy, with careful consideration of bleeding risk given the recent stroke. 1

Primary Recommendation: Anticoagulation

Oral anticoagulation is mandatory for this patient due to ischemic dilated cardiomyopathy with presumed left ventricular dysfunction and high stroke risk. 1

Choice of Anticoagulant

• Prefer a DOAC (apixaban, rivaroxaban, dabigatran, or edoxaban) over warfarin unless contraindications exist, as DOACs demonstrate superior or non-inferior efficacy with reduced bleeding risks, including intracranial hemorrhage, no dietary restrictions, and no need for INR monitoring 2, 3, 4

• If warfarin is used, target INR 2.0-3.0 (target 2.5) for patients under 75 years, or INR 1.6-2.5 (target 2.0) for patients over 75 years at high bleeding risk 1

• Apixaban 5mg twice daily showed superior stroke prevention compared to warfarin with significantly reduced major bleeding 3

• Dabigatran 150mg twice daily demonstrated superiority to warfarin for stroke prevention with similar major bleeding rates 3

• Rivaroxaban 20mg once daily showed non-inferiority to warfarin with similar bleeding rates 3

Timing of Anticoagulation Initiation Post-Stroke

The critical decision is when to start anticoagulation after the acute ischemic stroke. 1

• For patients with cardioembolic stroke risk (which applies here due to cardiomyopathy), anticoagulation should typically be initiated 7-10 days after stroke onset to balance thromboembolic risk against hemorrhagic transformation risk 1

• Reversal and withholding of anticoagulation for 7-10 days post-stroke in patients with prosthetic valves or chronic atrial fibrillation was associated with only 5% embolic events, with safe reinstitution thereafter 1

• Earlier initiation may be considered for smaller strokes with lower hemorrhagic transformation risk, while larger strokes or those with hemorrhagic transformation require longer delays 1

Antiplatelet Therapy Considerations

Antiplatelet therapy should NOT be routinely combined with anticoagulation in this patient. 1

If Patient Has Concurrent Coronary Artery Disease Requiring PCI:

• Peri-PCI period: Triple therapy (OAC + aspirin + P2Y12 inhibitor) only during the procedure 1

• Post-discharge default strategy: Double therapy (OAC + P2Y12 inhibitor, preferably clopidogrel) should be started immediately 1

• Discontinue aspirin at hospital discharge for most patients to reduce bleeding risk 1

• In highly selected patients at high ischemic/thrombotic risk and low bleeding risk, triple therapy may be extended up to 1 month maximum, but this is rarely indicated 1

• Transition to OAC monotherapy at 6-12 months depending on bleeding and ischemic risk stratification 1

If No Recent PCI or ACS:

• Anticoagulation monotherapy is the appropriate strategy 1, 2

• Do not add aspirin or other antiplatelet agents as this significantly increases bleeding risk without proven benefit in patients on anticoagulation for cardiomyopathy 1

Bleeding Risk Mitigation

Given the recent stroke and elderly age, this patient is at elevated bleeding risk. 1

• Prescribe a proton pump inhibitor (PPI) in combination with anticoagulation to reduce gastrointestinal bleeding risk 1

• Age ≥75 years is a minor criterion for high bleeding risk 1

• Recent stroke with potential for hemorrhagic transformation increases bleeding concern 1

Specific Contraindication: Avoid Dual Antiplatelet Therapy

Do not use dual antiplatelet therapy (aspirin + clopidogrel) as monotherapy in this patient instead of anticoagulation. 1, 2

• Antiplatelet therapy is recommended for non-cardioembolic stroke (atherothrombotic, lacunar, cryptogenic) 5

• This patient has cardioembolic risk from ischemic cardiomyopathy, making anticoagulation superior to antiplatelet therapy 1, 2, 6

• Single or dual antiplatelet therapy would be inadequate for preventing cardioembolic stroke in the setting of dilated cardiomyopathy 1

Monitoring and Follow-Up

• If using warfarin, maintain INR in therapeutic range with regular monitoring 1

• If using DOAC, assess renal function regularly as most require dose adjustment for renal impairment 2

• Monitor for bleeding complications, particularly intracranial hemorrhage given recent stroke 1

• Assess for signs of heart failure progression, as worsening LV dysfunction (ejection fraction <35%) strengthens the indication for anticoagulation 1

Critical Pitfalls to Avoid

• Never use antiplatelet monotherapy or dual antiplatelet therapy as a substitute for anticoagulation in patients with cardiomyopathy and stroke 1

• Never combine long-term anticoagulation with dual antiplatelet therapy outside the specific PCI context, as bleeding risk far exceeds any potential benefit 1

• Never start anticoagulation immediately after acute stroke without considering hemorrhagic transformation risk—wait 7-10 days for most patients 1

• Never discharge without a PPI if the patient is on anticoagulation, especially if elderly or at gastrointestinal bleeding risk 1

• Never use warfarin without careful INR monitoring and patient education about dietary interactions and bleeding precautions 1