TIA vs Minor Stroke: Dual Antiplatelet Windows & Imaging Strategy

Transient ischemic attack (TIA) and minor ischemic stroke share urgent pathways: rapid imaging to exclude hemorrhage/large vessel occlusion, early antithrombotics, carotid/AF workup, and aggressive risk reduction. The trick is timing—DAPT windows are short—and not missing posterior or “disabling-but-low-NIHSS” strokes.

Definitions that drive decisions

• TIA: focal neuro symptoms from ischemia with resolution and no infarct on imaging.
• Minor ischemic stroke: persistent deficit with typically NIHSS ≤3 (some use ≤5). Beware: low NIHSS can still be disabling (aphasia, hemianopia, dominant-hand weakness).

First 10 minutes — parallel workflow

• Stroke alert if within lysis/thrombectomy windows; check glucose, vitals, last-known-well, meds (DOAC/warfarin).
• Non-contrast CT head immediately to rule out hemorrhage; add CTA head/neck to evaluate large-vessel occlusion (LVO) and carotids/vertebrals.
• ECG, labs (CBC, CMP, PT/INR, PTT, troponin when indicated).

Reperfusion therapy checks (don’t miss)

• IV thrombolysis (alteplase/tenecteplase) if disabling deficit within guideline time and no contraindications—even if NIHSS is “minor” but functionally disabling.
• Mechanical thrombectomy for LVO within 0–6 h, and 6–24 h in select patients using perfusion imaging criteria.

MRI & risk scoring

• MRI DWI confirms infarct and detects posterior strokes missed by CT; DWI-negative with symptom resolution supports TIA.
• ABCD² (Age, BP, Clinical features, Duration, Diabetes) estimates early risk; ABCD³-I adds dual events, imaging, and carotid stenosis for better triage. Use scores to triage speed, not to replace imaging.

Antithrombotics — the DAPT windows

Start after hemorrhage excluded and no immediate plan for lysis/procedures.

• Aspirin + clopidogrel for 21 days in high-risk TIA or minor stroke started within 24 h of onset (short course, then single antiplatelet).
• Aspirin + ticagrelor for up to 30 days is an alternative in selected patients (e.g., clopidogrel resistance or symptomatic atherosclerosis), then step down to single agent.
• Do not use long-term DAPT in non-cardioembolic stroke—bleeding outweighs benefit beyond the early window.
• Cardioembolism suspected/AF found: use anticoagulation (DOAC/warfarin) rather than antiplatelets; timing after stroke depends on infarct size/bleed risk (e.g., “1–3–6–12 day” style rules—follow local protocol).

Carotid & vertebral disease — fix the plumbing

• Symptomatic carotid stenosis 70–99% → endarterectomy (or stenting when appropriate), ideally within 2 weeks of event; consider for 50–69% individually.
• Vertebral-basilar atherosclerosis: control risk factors; endovascular options individualized with neurointervention.

Cardioembolic search

• Telemetry 24–72 h minimum; consider prolonged ambulatory monitoring for occult AF.
• Echocardiography (TTE ± TEE) for LV thrombus, valvular disease, PFO in select young patients, and aortic arch atheroma.

Blood pressure, lipids, glucose

• Acute BP: if no thrombolysis, generally avoid aggressive BP lowering in first 24–48 h unless >220/120 mmHg or other indications; if thrombolysis given, keep <185/110 before and <180/105 after per protocol.
• Statin: initiate high-intensity statin for atherosclerotic ischemic events unless contraindicated.
• Diabetes: reasonable A1c target around ~7%; avoid hypoglycemia.

Secondary prevention bundle

• Antithrombotic plan (short DAPT → single antiplatelet, or anticoagulation for AF).
• BP control (often target <130/80), lipid lowering, smoking cessation, diet/exercise, weight, sleep apnea screening.
• Education: symptom recognition, EMS activation, med adherence.

Pearls & pitfalls

• Low NIHSS can still be disabling—consider lysis if within window and risk acceptable.
• Posterior circulation symptoms (vertigo, ataxia, diplopia) need MRI; CT can be falsely reassuring early.
• Start DAPT early but stop at 21–30 days to avoid excess bleeding.

Patient FAQs

“Why two blood thinners only for a few weeks?” Dual therapy lowers early re-stroke risk the most in the first weeks, but keeping both long-term raises bleeding risk without added benefit.

“If my CT was normal, was it really a stroke?” CT can look normal early; MRI shows tiny infarcts and helps confirm. Normal imaging with full recovery often means TIA—still a serious warning.

References & Notes

Pragmatic TIA/minor stroke pathway: fast CT/CTA, consider MRI, early short-course DAPT for non-cardioembolic events, carotid/AF workup, and aggressive risk reduction. Local protocols vary—follow institutional guidance. Educational only.