Foetal radiation exposure caused by mechanical thrombectomy in large-vessel ischaemic stroke in pregnancy

Acute Ischemic Stroke in Pregnancy : A Practical Focus on Neuroimaging and Reperfusion Therapy

INTRODUCTION

Pregnancy increases the risk of acute ischemic stroke (AIS) among young women and is responsible for about 5% of maternal deaths and significant disability. Concerns of potential adverse events of imaging and reperfusion therapies in this group of patients can lead to a substantial delay or omission of treatment that can significantly worsen outcomes.

OBJECTIVE

The objective of this study is to discuss main concerns of diagnosis and therapy of pregnant patients with AIS regarding neuroimaging and reperfusion treatment.

RESULTS

The cumulative radiation dose of computed tomography (CT)-based entire diagnostic procedure (noncontrast CT, CT-angiography and CT-perfusion) is estimated to be below threshold for serious fetal radiation exposure adverse events. Similarly, magnetic resonance imaging(MRI)-based imaging is thought to be safe as long as gadolinium contrast media are avoided. The added risk of intravenous thrombolysis (IVT) and mechanical thrombectomy during pregnancy is thought to be very low. Nevertheless, some additional safety measures should be utilized to reduce the risk of radiation, contrast media and hypotension exposure during diagnostic procedures or reperfusion treatment.

CONCLUSION

Fetal safety concerns should not preclude routine diagnostic work-up (except for gadolinium contrast media administration) in childbearing AIS women, including procedures applied in unknown onset and late onset individuals. Due to rather low added risk of serious treatment complications, pregnancy should not be a sole contraindication for neither IVT, nor endovascular treatment.

Pregnancy-Related Stroke: A Review

Importance

The maternal risk of strokes in the United States is approximately 30/100,000 pregnancies, and strokes are the eighth leading cause of maternal death. Because of the relationship between stroke and significant neurological disability/maternal death, obstetrical health care providers must be able to identify, evaluate, diagnosis, and treat these women.

Evidence Acquisition

PubMed was searched using the search terms "stroke" OR "cerebrovascular accident" OR "intracranial hemorrhage" AND "pregnancy complications" OR "risk factors" OR "management" OR "outcome." The search was limited to the English language and was restricted to articles from 2000 to 2020.

Results

There were 319 abstracts identified, and 90 of the articles were ultimately used as the basis of this review. Presenting stroke signs and symptoms include headache, composite neurologic defects, seizures, and/or visual changes. Diagnosis is typically made with computed tomography scan using abdominal shielding or magnetic resonance imaging without contrast. Management options for an ischemic stroke include reperfusion therapy with intravenous recombinant tissue plasminogen activator catheter-based thrombolysis and/or mechanical thrombectomy. Hemorrhagic strokes are treated similarly to strokes outside of pregnancy, and that treatment is based on the severity and location of the hemorrhage.

Conclusions and Relevance

Early recognition and management are integral in decreasing the morbidity and mortality associated with a stroke in pregnancy.

Relevance Statement

This study was an evidence-based review of stroke in pregnancy and how to diagnose and mange a pregnancy complicated by a stroke.

European Stroke Organisation guidelines on stroke in women: Management of menopause, pregnancy and postpartum

Pregnancy, postpartum and menopause are regarded as periods women are more vulnerable to ischaemic events. There are conflicting results regarding stroke risk and hormone replacement therapy (HRT) during menopause. Stroke in pregnancy is generally increasing with serious consequences for mother and child; therefore, recommendations for acute treatment with intravenous thrombolysis (IVT) and/or mechanical thrombectomy (MT) are needed. The aim of this guideline is to support and guide clinicians in treatment decisions in stroke in women. Following the "Grading of Recommendations and Assessment, Development and Evaluation (GRADE)" approach, the guidelines were developed according to the European Stroke Organisation (ESO) Standard Operating Procedure. Systematic reviews and metanalyses were performed. Based on available evidence, recommendations were provided. Where there was a lack of evidence, an expert consensus statement was given. Low quality of evidence was found to suggest against the use of HRT to reduce the risk of stroke (ischaemic and haemorrhagic) in postmenopausal women. No data was available on the outcome of women with stroke when treated with HRT. No sufficient evidence was found to provide recommendations for treatment with IVT or MT during pregnancy, postpartum and menstruation. The majority of members suggested that pregnant women can be treated with IVT after assessing the benefit/risk profile on an individual basis, all members suggested treatment with IVT during postpartum and menstruation. All members suggested treatment with MT during pregnancy. The guidelines highlight the need to identify evidence for stroke prevention and acute treatment in women in more vulnerable periods of their lifetime to generate reliable data for future guidelines.

A Case of an Early Pregnant Woman with Congenital Protein S Deficiency Who Underwent Mechanical Thrombectomy

Objective

Large vessel occlusion (LVO) stroke during pregnancy is rare but a life-threatening issue for the mother and fetus. We report a rare case of a pregnant woman with congenital protein S deficiency who underwent mechanical thrombectomy.

Case Presentation

A 35-year-old woman presented with right hemiplegia and aphasia. The National Institutes of Health Stroke Scale was 23 and MRI revealed acute infarction on the left hemisphere. MRA showed disruption of the left middle cerebral artery. Mechanical thrombectomy was performed following intravenous thrombolysis, and then complete recanalization was achieved. The reduction in protein S activity due to pregnancy was suspected to have affected LVO. Subsequently, the patient was diagnosed with congenital protein S deficiency and recovered to modified Rankin scale 2 at 3 months after the onset.

Conclusion

Aggravation of congenital protein S deficiency due to pregnancy led to the onset of LVO. The patient showed a good outcome after mechanical thrombectomy.

Neurocritical Care of the Pregnant Patient

Purpose of review

To summarize recent changes in management and emerging therapies for pregnant neurocritical care patients.

Recent findings

Diagnostic and treatment options for managing neurologic emergencies in pregnant patients have expanded with both greater understanding of the effects of imaging modalities and medications on pregnancy and application of standard treatments for non-pregnant patients to pregnant populations. Specifically, this includes cerebrovascular diseases (pregnancy-associated ischemic stroke, pregnancy-associated intracerebral hemorrhage, cerebral venous sinus thrombosis), post-maternal cardiac arrest care, seizures and status epilepticus, myasthenia gravis, and fetal somatic support in maternal death by neurologic criteria.

Summary

With the exception of direct abdominal computed tomography (CT), most imaging studies are reasonably safe in pregnancy. When emergent imaging is needed to prevent maternal morbidity or mortality, any CT sequence with or without contrast is appropriate to pursue. Though new safety data on antiplatelets, antihypertensives, thrombolytics, and antiepileptic drugs have increased options for disease management in pregnancy, unfractionated and low-molecular weight heparin remain the safest options for anticoagulation. Early studies on hypothermia, ketamine, and immunomodulating therapies in pregnancy are promising. In myasthenia gravis, new data on adjunct devices may allow more patients to undergo safe vaginal delivery, avoiding cesarean section and the associated risk of crisis. When difficult decisions regarding preterm delivery arise, recent outcome studies can help inform discussion. Lastly, when the feared complication of maternal death by neurologic criteria occurs, fetal somatic support may help to save at least one life.

Thrombolysis and Mechanical Thrombectomy for Acute Ischemic Stroke in Pregnancy: A Case Report

Objective

Intravenous (IV) recombinant tissue plasminogen activator (rt-PA) and mechanical thrombectomy (MT) are effective treatments for acute ischemic stroke (AIS). However, the treatment for AIS in pregnancy is not established because no clinical trials have included pregnant patients. We present a case of middle cerebral artery (MCA) M2 segment occlusion in pregnancy treated with IV thrombolysis and endovascular therapy.

Case Presentation

A 36-year-old woman being 6 weeks pregnant presented with right-sided hemiparesis and aphasia. MRI showed a high-intensity area on diffusion-weighted imaging of the left parietal lobe, and MRA showed left MCA M2 segment occlusion. She underwent IV rt-PA and MT and achieved thrombolysis in cerebral infarction 2b revascularization without complications. The protein S concentration was lower than that in the physiological changes during pregnancy. She was diagnosed with embolic stroke related to coagulopathy in pregnancy, and she underwent anticoagulation. At the 3-month follow-up, the modified Rankin Scale was 0. She miscarried at 4 months, and the fetal death was presumed to be obstetric cause.

Conclusion

IV rt-PA and MT may be effective and safe treatments for pregnant patients. Estimated fetal radiation exposure during MT is low and is presumed not to affect fetal development. We should mitigate the radiation dose and reduce the dose of iodinated contrast agents, particularly in pregnant patients.

Mechanical thrombectomy for acute stroke in pregnancy

Several recent randomised control trials have shown adjunctive endovascular mechanical thrombectomy to be an effective and safe treatment for acute stroke superior to medical therapy alone. Despite this, questions remain over certain groups of patients that have been excluded from these studies, such as pregnant women. We believe this is a topic of increasing clinical significance with minimal data in the literature. In this article we discuss stroke in pregnancy and highlight the important technical considerations of endovascular mechanical thrombectomy, including minimising radiation exposure to the mother and fetus.