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Cerebral microbleeds and postthrombolysis intracerebral hemorrhage risk Updated meta-analysis
Objective:
We performed a systematic review and meta-analysis to assess whether the presence of cerebral microbleeds (CMBs) on pretreatment MRI scans of patients with acute ischemic stroke treated with thrombolysis is associated with an increased risk of symptomatic intracerebral hemorrhage (ICH).
Methods:
We searched PubMed for relevant studies and calculated pooled odds ratios (ORs) for symptomatic ICH, using the Mantel–Haenszel fixed-effects method, among individuals with vs without CMBs on pretreatment MRI scans. To minimize potential bias, sensitivity analysis was performed including studies providing data on patients treated only with IV thrombolysis.
Results:
Ten eligible studies including 2,028 patients were pooled in meta-analysis. The overall prevalence of CMBs was 23.3%. Among patients with CMBs, 40 of 472 (8.5%; 95%confidence interval [CI]: 6.1%–11.4%) experienced a symptomatic ICH after thrombolysis compared with 61 of 1,556 patients (3.9%; 95% CI: 3%–5%) without CMBs. The pooled OR of ICH across all studies was 2.26 (95%CI: 1.46–3.49; p , 0.0001). Eight studies, including 1,704 patients (n 5 401 with CMBs), provided data on patients treated with IV thrombolysis only; OR for the presence of CMBs and the development of symptomatic ICH was 2.87 (95%CI: 1.76–4.69; p , 0.0001).
Conclusions:
Our meta-analysis of the available published data demonstrates an increased risk of symptomatic ICH after thrombolysis for acute ischemic stroke in patients with CMBs. However, we cannot fully exclude bias or confounding, so our results should be considered hypothesis generating. Detecting CMBs should not prevent thrombolytic treatment based on present evidence. Further analyses, taking into account CMB number and location, as well as measures of functional outcome, are needed.
Insights
Patients with cerebral microbleeds (CMBs) on MRI scans have a higher risk of symptomatic intracerebral hemorrhage (ICH) after thrombolysis for acute ischemic stroke. Detecting CMBs should not halt thrombolytic treatment, but further research is needed.
Area of Science:
- Neurology
- Radiology
- Cardiovascular Medicine
Background:
- Cerebral microbleeds (CMBs) are small, punctate hemorrhages often detected on MRI.
- The association between CMBs and the risk of symptomatic intracerebral hemorrhage (ICH) following thrombolysis for acute ischemic stroke is not fully established.
Purpose of the Study:
- To systematically review and meta-analyze the risk of symptomatic ICH in acute ischemic stroke patients treated with thrombolysis who have pretreatment CMBs on MRI.
Main Methods:
- A systematic literature search was conducted on PubMed.
- Pooled odds ratios (ORs) for symptomatic ICH were calculated using a fixed-effects model.
- Sensitivity analysis was performed on studies using only intravenous thrombolysis.
Main Results:
- Ten studies with 2,028 patients were included. Overall CMB prevalence was 23.3%.
- Patients with CMBs had a significantly higher risk of symptomatic ICH (OR: 2.26; 95% CI: 1.46–3.49).
- For IV thrombolysis only, the OR for CMBs and symptomatic ICH was 2.87 (95% CI: 1.76–4.69).
Conclusions:
- Pretreatment cerebral microbleeds are associated with an increased risk of symptomatic intracerebral hemorrhage after thrombolysis for acute ischemic stroke.
- Current evidence suggests CMB detection should not contraindicate thrombolytic therapy.
- Further research is needed to analyze CMB number, location, and functional outcomes.
