What to do for a 73-year-old patient with hypertension and recent stroke, on aspirin and Plavix, presenting with acute vision loss after TNK administration?

Management of Acute Vision Loss in a Patient with Recent Stroke and TNK Treatment

For a 73-year-old patient with hypertension and recent stroke who developed acute right vision loss after TNK administration and is currently on dual antiplatelet therapy, immediate referral to an emergency department with stroke center capabilities is required for evaluation of central retinal artery occlusion (CRAO).

Immediate Actions

1. Recognize this as a medical emergency:

   • Acute vision loss following thrombolytic therapy (TNK) requires immediate attention
   • CRAO is considered a stroke equivalent with high risk of additional cerebrovascular events 1
   • Risk of stroke is highest within the first 7 days of visual symptoms 2

2. Emergency referral:

   • Transfer immediately to the nearest emergency department affiliated with a stroke center
   • Do not delay for additional ophthalmic testing 1
   • Communicate the patient's recent stroke history, TNK treatment, and current dual antiplatelet therapy

Diagnostic Evaluation at Stroke Center

The stroke center should perform:

• Brain MRI with diffusion-weighted imaging (preferred) or CT if MRI unavailable 1
• Vascular imaging (MRA, CTA, or carotid ultrasound) 1
• Cardiac evaluation including ECG and monitoring 1
• Laboratory tests including CBC, chemistry panel, lipid panel, HbA1c 1
• For patients >50 years: ESR and CRP to rule out giant cell arteritis 1
• Ophthalmologic consultation for confirmation of CRAO diagnosis

Management Considerations

1. Antithrombotic therapy:

   • Patient is already on aspirin and clopidogrel (Plavix) for one month following recent stroke
   • For CRAO in a patient with recent stroke, continuing dual antiplatelet therapy is reasonable 1
   • The THALES trial suggests that ticagrelor with aspirin may be considered as an alternative 1

2. Hypertension management:

   • Optimize blood pressure control as hypertension is present in nearly 50% of retinal vascular occlusion cases 2
   • Follow established stroke guidelines for target blood pressure ranges

3. Additional interventions to consider:

   • Limited evidence exists for effective interventional treatments for CRAO 2
   • Options that may be considered by specialists include:
     • Anterior chamber paracentesis
     • Ocular massage
     • Vasodilatory treatments
     • Hyperbaric oxygen therapy in select cases

Follow-up Care

1. Ophthalmologic follow-up:

   • Schedule within 1-2 weeks to monitor for complications
   • Regular monitoring for neovascularization which may require panretinal photocoagulation 1
   • Assessment for preservation of residual vision 1

2. Neurologic follow-up:

   • Within 2 weeks to review test results and optimize secondary stroke prevention 2
   • Multidisciplinary approach involving neurologist, ophthalmologist, and primary care physician 1

3. Risk factor modification:

   • Aggressive management of vascular risk factors
   • Statin therapy for hyperlipidemia
   • Smoking cessation if applicable
   • Diet and exercise counseling

Important Caveats

• Delay in referral decreases chance of good outcome by 8-14% for every 30-minute delay 2
• Up to 70% of patients with CRAO have significant systemic cardiovascular conditions 2
• The patient's recent thrombolytic therapy (TNK) and current dual antiplatelet therapy increase bleeding risk, which must be considered in any additional interventions
• Vision rehabilitation services should be considered if significant vision loss persists 1