A 58-year-old man from Delhi presents to the emergency department with acute onset right-sided weakness and speech difficulty for 2 hours. Non-contrast CT head shows no hyperdensity. What is the most appropriate next step in management?

## Clinical Context This patient presents with acute ischemic stroke symptoms within the thrombolytic window (2 hours from onset). Non-contrast CT head has already excluded intracranial hemorrhage — the primary contraindication to thrombolysis. He has no stated contraindications, making him a candidate for immediate IV thrombolysis. ## Why Administer IV Alteplase Immediately? **Key Point:** Per AHA/ASA 2019 guidelines and Indian Stroke Association protocols, once hemorrhage is excluded on non-contrast CT, IV alteplase (0.9 mg/kg, max 90 mg) should be administered **without delay** in eligible patients within the 4.5-hour window. "Time is brain" — every 1-minute delay in treatment results in approximately 1.9 million neurons lost. **High-Yield:** The non-contrast CT serves as the gating study to rule out hemorrhage. Additional MRI with DWI/PWI, while useful for confirming ischemia and assessing penumbra, is **NOT required before thrombolysis** and would cause harmful delays. AHA/ASA guidelines explicitly state that MRI should not delay IV alteplase administration. ## Management Algorithm ``` Acute stroke symptoms < 4.5 hrs ↓ Non-contrast CT (done ✓) → No hemorrhage ↓ Eligible for thrombolysis? → Yes ↓ IV Alteplase IMMEDIATELY (± concurrent CTA for LVO/thrombectomy candidacy) ``` **Clinical Pearl:** CTA of neck and intracranial vessels is recommended **concurrently** with or immediately after alteplase administration to assess for large vessel occlusion (LVO) and thrombectomy candidacy — but this does not precede or replace thrombolysis in eligible patients. Delaying alteplase to perform MRI DWI/PWI is not guideline-recommended practice. ## Why the Other Options Are Wrong - **Option B (MRI DWI/PWI first):** While MRI is the gold standard for confirming ischemia, guidelines do not mandate MRI before thrombolysis. Performing MRI first wastes critical time in the reperfusion window. - **Option C (Observe 24 hours):** Completely inappropriate — this patient is within the treatment window and observation would result in irreversible neuronal loss. - **Option D (Aspirin + CTA neck):** Aspirin is not the first-line acute treatment within the thrombolytic window; CTA is useful but should not replace or precede alteplase in an eligible patient. **High-Yield:** The correct sequence is: Non-contrast CT (done) → rule out hemorrhage → IV alteplase immediately → concurrent CTA for LVO assessment → mechanical thrombectomy if LVO confirmed. [cite: AHA/ASA Stroke Guidelines 2019; Harrison's Principles of Internal Medicine 21e, Ch. 379; Indian Stroke Association Guidelines 2020]