Hemorrhagic Transformation in Acute Ischemic Stroke: A Quantitative Systematic Review

Area of Science:

• Neurology
• Cardiovascular Research
• Medical Imaging

Background:

• Hemorrhagic transformation (HT) is a significant complication following acute ischemic stroke.
• The prevalence and specific risk factors for HT, including hemorrhagic infarction (HI) and parenchymal hematoma (PH), require further delineation.

Purpose of the Study:

• To systematically review and meta-analyze the prevalence and risk factors of HT after acute ischemic stroke.
• To compare HT rates in patients treated with intravenous thrombolysis (IV-tPA) versus those without.

Main Methods:

• Systematic review and meta-analysis of prospective observational studies published from 1985-2017.
• Inclusion of studies using ECASS-2 definitions for HI and PH.
• Comparison of outcomes between patients receiving IV-tPA and those not receiving thrombolysis.

Main Results:

• Overall HT prevalence was 27% (32% with IV-tPA vs. 20% without).
• Overall PH prevalence was 9% (12% with IV-tPA vs. 5% without).
• HT associated with atrial fibrillation (OR 2.94), anticoagulants (OR 2.47), higher NIHSS, and larger infarct volume. PH in IV-tPA patients correlated with antiplatelet (OR 3) and statin use (OR 4). Both HT and PH linked to poor 90-day outcomes (OR 3 and 8, respectively).

Conclusions:

• Hemorrhagic transformation is a frequent complication of acute ischemic stroke with significant associations with specific risk factors.
• HT and PH are linked to poorer patient outcomes, emphasizing the need for risk factor recognition and management.