Neglecting the difference: does right or left matter in stroke outcome after thrombolysis?

Area of Science:

• Neurology
• Stroke Medicine
• Neuroimaging

Background:

• Right hemispheric strokes (RHS) are associated with delayed emergency department presentation, reduced likelihood of receiving IV rt-PA, and poorer outcomes compared to Left Hemispheric Strokes (LHS).
• Understanding hemispheric differences in stroke treatment response is crucial for optimizing patient care.

Purpose of the Study:

• To analyze the outcomes of IV rt-PA treatment in acute stroke patients based on the affected cerebral hemisphere.
• To identify predictors of neurological improvement and good functional outcome after IV rt-PA.

Main Methods:

• Prospective cohort study of acute stroke patients treated with IV rt-PA from December 1998 to March 2003.
• Univariate and logistic-regression analyses were employed to compare RHS and LHS groups and identify independent predictors of outcomes at 24 hours and 3 months.

Main Results:

• Patients with RHS had lower pretreatment National Institutes of Health Stroke Scale (NIHSS) scores and were less hypertensive than those with LHS.
• Left hemispheric stroke (LHS) was an independent predictor of both major neurological improvement at 24 hours (OR, 2.07) and good outcome at 3 months (OR, 2.29).
• Female sex and lower pretreatment NIHSS scores also predicted major neurological improvement, while age and pretreatment NIHSS predicted 3-month outcome.

Conclusions:

• Patients with LHS demonstrate a significantly higher likelihood of achieving a good outcome 3 months post-IV rt-PA treatment compared to RHS patients, even with higher initial stroke severity.
• The observed difference in outcomes between LHS and RHS is detectable as early as 24 hours after treatment.
• Future research should integrate neuroimaging and hemodynamic data to further elucidate factors influencing stroke outcomes based on hemispheric involvement.