Moyamoya-disease-related ischemic stroke in the postpartum period

The risk for future cerebrovascular disease in pregnant women with Moyamoya disease: a nationwide population-based study in South Korea

Background

Physiologic changes during pregnancy affect the development of postpartum cerebrovascular disease (CVD) in women with Moyamoya disease. Due to the rare prevalence of Moyamoya disease and its large regional variations, large-scale based studies on the risk of CVD after delivery have not been conducted. This study aimed to evaluate whether women with Moyamoya disease have an increased risk of CVD after delivery.

Methods

Research data was collected from the National Health Insurance Claims Database of the Health Insurance Review and Assessment Service. Patients who delivered in Korea from 2007 to 2014 were enrolled in this study. We classified women as having CVD if they were diagnosed with any of the following conditions between delivery and December 31, 2016; cerebral infarction (I63.X in the International Classification of Diseases-10th Revision [ICD-10]) and/or intracranial hemorrhage (I61.X, I62.X in ICD-10) and/or subarachnoid hemorrhage (I60.X in ICD-10). Women with Moyamoya disease were identified as having I67.5 in ICD-10. We matched the study cohort by the ratio of 1:10 to analyze the risk CVD occurrence. The matching technique applied in this study was based on the variables of age and parity. To evaluate the adjusted hazard ratio (HR) for CVD in women with Moyamoya disease, we used multivariate Cox proportional hazard regression.

Results

Among a total of 3,611,216 Korean women who underwent delivered, we identified 412 women with Moyamoya disease diagnosis and 1420 age- and parity-matched women without Moyamoya disease (control). Compared to the control group, women with Moyamoya disease had a significantly higher rate of Cesarean section, overt DM, and essential hypertension (all p < 0.0001). Among women with Moyamoya disease, 55 (13.35%) women developed CVD within the follow-up postpartum period. The presence of Moyamoya disease was associated with an increased risk of CVD after delivery (adjusted HR 37.42; 95% confidence interval (CI) 17.50-80.02 within 2.3 years) after adjusting for pregnancy-induced hypertension, gestational diabetes mellitus, pregestational diabetes, chronic hypertension.

Conclusion

This population based study showed that the occurrence rate of CVD after delivery was higher in women with Moyamoya disease than in those without. Therefore, careful and long-term postpartum surveillance is required for women with Moyamoya disease.

Deficiency in CD4 T Cells Leads to Enhanced Postpartum Internal Carotid Artery Vasoconstriction in Mice: The Role of Nitric Oxide

The risk of postpartum (PP) stroke is increased in complicated pregnancies. Deficiency in CD4 T cell subsets is associated with preeclampsia and may contribute to PP vascular disease, including internal carotid artery (ICA) stenosis and stroke. We hypothesized that CD4 T cell deficiency in pregnancy would result in ICA dysregulation, including enhanced ICA vasoconstriction. We characterized the function, mechanical behavior, and structure of ICAs from C57BL/6 (WT) and CD4 deficient (CD4KO) mice, and assessed the role of NO in the control of ICA function at pre-conception and PP. WT and CD4KO mice were housed under pathogen-free conditions, mated to same-strain males, and allowed to litter or left virgin. At 3 days or 4 weeks PP, mice were euthanized. The responses to phenylephrine (PE), high K⁺ and acetylcholine (ACh) were assessed in pressurized ICAs before and after NOS inhibition. Passive lumen diameters were measured at 3–140 mmHg. eNOS and iNOS expression as well as the presence of T cells were evaluated by immunohistochemistry. Constriction of WT ICAs to PE was not modified PP. In contrast, responses to PE were significantly increased in ICAs from PP as compared to virgin CD4KO mice. Constriction to high K⁺ was not enhanced PP. ICAs from WT and CD4KO mice were equally sensitive to ACh with a significant rightward shift of dose-response curves after L-NNA treatment. NOS inhibition enhanced PE constriction of ICAs from WT virgin and PP mice. Although a similar effect was detected in ICAs of virgin CD4KO mice, no such changes were observed in vessels from PP CD4KO mice. Passive arterial distensibility at physiological levels of pressure was not modified at PP. ICA diameters were significantly increased in PP with no change in vascular wall thickness. Comparison of eNOS expression in virgin, 3 days and 4 weeks PP revealed a reduced expression in ICA from CD4 KO vs. WT PP vessels which reached significance at 4 weeks PP. iNos expression was similar and decreased over the PP period in vessels from WT and CD4KO mice. Dysregulation of the CD4 T cell population in pregnancy may make ICA vulnerable to vasospasm due to decreased NO-dependent control of ICA constriction. This may lead to cerebral hypoperfusion and increase the risk of maternal PP stroke.

Maternal Stroke: A Call for Action

Maternal mortality rates have been steadily increasing in the United States, and cardiovascular mortality is the leading cause of death among pregnant and postpartum women. Maternal stroke accounts for a significant burden of cardiovascular mortality. Data suggest that rates of maternal stroke have been increasing in recent years. Advancing maternal age at the time of birth and the increasing prevalence of traditional cardiovascular risk factors, and other risk factors, as well, such as hypertensive disorders of pregnancy, migraine, and infections, may contribute to increased rates of maternal stroke. In this article, we provide an overview of the epidemiology of maternal stroke, explore mechanisms that may explain increasing rates of stroke among pregnant women, and identify key knowledge gaps for future investigation in this area.

Moyamoya Disease in Pregnancy: A 20-Year Single-Center Experience and Literature Review

BACKGROUND

Pregnancy is a potential risk factor for stroke in women with Moyamoya disease. However, the rarity of the disease has limited clinical expertise to ensure a healthy pregnancy. The aim of the present study was to explore the possible risk factors for hemorrhagic and ischemic stroke in pregnant women with Moyamoya disease.

METHODS

A retrospective review of cases in our hospital during a 20-year period and a review of the reported data were conducted to investigate pregnancy-related cerebrovascular events in women with Moyamoya disease.

RESULTS

Thirty pregnancies in 20 women with Moyamoya disease were identified in the case review of our hospital. All were previously diagnosed cases, and no stroke had occurred during the study period. In the reported data review, pregnancy-related stroke in women with Moyamoya disease was identified in 54 (44 intracranial hemorrhage and 10 cerebral infarction). Intracranial hemorrhage occurred most commonly during the antepartum period (n = 39; 88.6%), with most events occurring at ≥24 weeks. Of the intracranial hemorrhage cases, 7 (15.9%) were complicated by hypertensive disorders of pregnancy, and 8 patients (18.2%) died of stroke. The onset of cerebral infarction was either in the antepartum (n = 4; 40.0%) or postpartum (n = 6; 60.0%) period. All postpartum cases occurred within 3-7 days after delivery.

CONCLUSION

Pregnancy-related stroke in patients with Moyamoya disease might be susceptible to gestational age. Intracranial hemorrhage is prone to occur during the antepartum period, especially at ≥24 weeks, and cerebral infarction tends to occur postpartum.

Neurologic Deterioration in Patients with Moyamoya Disease during Pregnancy, Delivery, and Puerperium

BACKGROUND

We reviewed our clinical experience of patients with moyamoya disease (MMD) who gave birth and assessed characteristics of those experiencing neurologic deterioration.

METHODS

The patients were classified into patients diagnosed with MMD during pregnancy and puerperium (group 1) and those diagnosed before pregnancy (group 2). We retrospectively reviewed patient characteristics, MMD treatment, neurologic symptoms before and during pregnancy and/after puerperium, obstetrical history, and delivery type in groups 1 and 2.

RESULTS

Group 1 included 2 patients with deterioration of pre-existing transient ischemic attacks (TIAs) and acute cerebral infarction and 1 patient with seizures and newly developed TIAs during pregnancy and/or puerperium. Group 2 included 20 patients with 23 pregnancies. In group 2, 4 patients had deterioration of TIAs during pregnancy and puerperium. There were significant differences between the cases without neurologic deterioration and with deterioration in group 2 (TIAs ≥10 before pregnancy, 0% vs. 75%, P = 0.002; severely reduced regional cerebrovascular reserve on single-photon emission computed tomography, 10.5% vs. 100%, P = 0.002; and surgical revascularization before pregnancy, 75% vs. 15.8%, P = 0.04). In groups 1 and 2, 6 of the 7 cases in which TIAs occurred or worsened during pregnancy or puerperium recovered to prepregnancy TIA levels after puerperium.

CONCLUSIONS

Patients with severely reduced regional cerebrovascular reserve on single-photon emission computed tomography and frequent TIAs before pregnancy may experience neurologic deterioration during pregnancy, delivery, and puerperium. Surgical revascularization before pregnancy may decrease neurologic deterioration during these periods.

Pregnancy outcomes in women with moyamoya disease: experiences at a single center in Korea

PURPOSE

Moyamoya disease (MMD) occurs predominantly in Korean and Japanese women. The aim of this study was to investigate clinical features and pregnancy outcomes in women with MMD.

MATERIALS AND METHODS

We conducted a retrospective chart review of women with MMD who visited our Department of Obstetrics and Gynecology between January 2005 and October 2013. For all study subjects, clinical features, demographic characteristics, and perinatal outcomes were recorded.

RESULTS

We identified 28 pregnancies in 22 patients who had been diagnosed with MMD. The mean maternal age at delivery was 31.9±3.5 years old. The mean gestational age at delivery was 38.0±0.9 weeks. Among the 28 pregnancies, 25 (92.5%) underwent cesarean section; 19 (76.0%) of them were performed under regional anesthesia and six (24.0%) under general anesthesia. The mean newborn weight was 3233.7±348.2 g. The 5-minute Apgar score in 85% of the newborns was higher than 8, with no other apparent complications. During the puerperal period, transient ischemic attack symptom or seizure occurred in 4 cases, although patients recovered within a few days.

CONCLUSION

For pregnant women with MMD, it is important to control blood pressure and prevent hyperventilation during the intrapartum period, and the best methods of delivery and anesthesia should be considered to avoid unfavorable sequelae. Additionally, a multidisciplinary approach (i.e., neurosurgery) is necessary to constantly manage underlying diseases.

A retrospective chart review of the perinatal period in 22 pregnancies of 16 women with Moyamoya disease

Moyamoya disease (MMD) is characterized by severe stenoses of the arteries in the circle of Willis, which predispose the patient to brain ischemia and intracranial hemorrhage. We performed a retrospective chart review of 22 pregnancies in 16 patients with MMD at the Kyushu University Hospital. An uncomplicated Cesarean delivery was performed in nearly all patients. In the 20 pregnancies in patients with pre-existing MMD, two had transient ischemic symptoms in the postpartum period. Two patients not previously known to have MMD developed transient ischemic symptoms postpartum. One of these patients was initially diagnosed and managed as pre-eclampsia. For patients diagnosed with MMD, a good perinatal outcome can be expected with appropriate management. Neurological events, however, may still occur postpartum even in well-managed patients. MMD may mimic the signs and symptoms of other neurological or psychiatric disorders, thereby complicating diagnosis and management.