Stroke and Stroke-like Episodes in Muscle Disease

Josef Finsterer

doi:10.2174/1874205x01206010026

Abstract

Background:Though not obvious at a first glance, myopathies may be associated with ischemic stroke. Stroke-like episodes resemble ischemic stroke only to some extent but are a unique feature of certain mitochondrial disorders with a pathogenesis at variance from that of ischemic stroke. Only limited data are available about ischemic stroke in pri-mary myopathies and the management of stroke-like episodes in mitochondrial disorders. This review aims to summarize and discuss current knowledge about stroke in myopathies and to delineate stroke-like episodes from ischemic stroke. Methods:Literature review via PubMED using the search terms “stroke”, “cerebrovascular”, “ischemic event”, “stroke-like episode”, “stroke-mimic”, “mitochondrial disorder”. Results:Stroke in myopathies is most frequently cardioembolic due to atrial fibrillation or atrial flutter, dilated cardio-myopathy, or left-ventricular hypertrabeculation (noncompaction). The second most frequent cause of stroke in myopathies is angiopathy from atherosclerosis or vasculitis, which may be a feature of inflammatory myopathies. Athero-sclerosis may either result from classical risk factors, such as diabetes, arterial hypertension, hyperlpidemia, or smoking, associated with muscle disease, or may be an inherent feature of a mitochondrial disorder. In case of severe heart failure from cardiomyopathy as a manifestation of muscle disease low flow infarcts may occur. Thrombophilic stroke has been described in polymyositis and dermatomyositis in association with anti-phospholipid syndrome. Stroke-like episodes occur particularly in mitochondrial encephalopathy, lactacidosis and stroke-likeepisode syndrome but rarely also in Leigh-syndrome and other mitochondrial disorders. Stroke-like episodes are at variance from ischemic stroke, pathogenically, clinically and on imaging. They may be the manifestation of a vascular, metabolic or epileptic process and present with predominantly vasogenic but also cytotoxic edema on MRI. Differentiation between ischemic stroke and stroke-like episodes is essential in terms of management and prognosis. Management of ischemic stroke in patients with myopathy is not at variance from the treatment of ischemic stroke in non-myopathic patients. There is no standardized treatment of stroke-like episodes but there is increasing evidence that these patients profit from the administration of L-arginine and conse-quent antiepileptic treatment if associated with seizure activity. Conclusions:Ischemic stroke may be a complication of myopathy and needs to be delineated from stroke-like episodes, which are unique to mitochondrial disorders, particularly mitochondrial encephalopathy, lactacidosis and stroke-likeepisode syndrome. Ischemic stroke in myopathies is most frequently cardioembolic and treatment is not at variance from non-myopathic ischemic stroke. Treatment of stroke-like episodes is not standardized but seems to respond to L-arginine and adequate antiepileptic treatment.

Highlights

Myopathies are a heterogeneous group of neurological disorders primarily affecting the striated skeletal muscle due to mutations in genes encoding for components of the myocyte or due to secondary affection of the muscle within the scope of a general disorder primarily affecting organs other than the muscle
This review aims to give an overview about the current knowledge concerning the relation between muscle disease and ischemic stroke and Stroke-like episodes (SLEs) with regard to pathogenesis, diagnosis, treatment and outcome
CLASSIFICATION OF ISCHEMIC STROKE Ischemic stroke is generally graded according to the TOAST-classification, which denotes five subtypes of is chemic stroke following its pathogenesis: 1) atherosclerosis of large arteries 2) cardioembolism, 3) small-vessel occlusion, 4) stroke due to other etiology, and 5) stroke of undetermined etiology [3]

Summary

Introduction

Myopathies are a heterogeneous group of neurological disorders primarily affecting the striated skeletal muscle due to mutations in genes encoding for components of the myocyte (primary myopathies) or due to secondary affection of the muscle within the scope of a general disorder primarily affecting organs other than the muscle (secondary myopathies). Stroke-like episodes (SLEs) are phenotypic features predominantly of mitochondrial disorders (MIDs), most. Narrowing or occlusion of large extra- or intracerebral arteries by arteriopathy or embolism leads to ischemia of the downstream vascular territory. Narrowing or occlusion of small intra-cerebral arteries by arteriopathy or embolism leads to ischemia only of a small vascular territory, morphologically manifesting as white matter lesions or lacunas. Strokelike episodes resemble ischemic stroke only to some extent but are a unique feature of certain mitochondrial disorders with a pathogenesis at variance from that of ischemic stroke. Limited data are available about ischemic stroke in primary myopathies and the management of stroke-like episodes in mitochondrial disorders. This review aims to summarize and discuss current knowledge about stroke in myopathies and to delineate stroke-like episodes from ischemic stroke

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Conclusion