![]() ![]() The M1 (horizontal branch) supplies the basal ganglia and M2 (Sylvian branches) supplies part of the parietal, frontal and temporal lobes. ![]() ![]() The MCA has the main trunk (M1) and it divides into two M2 Branches. So patients present with motor aphasia, personality issues, and contralateral leg weakness and numbness. So, pure ACA strokes are rare. The ACA distribution involves mainly Broca’s area, primary motor, primary sensory and pre-frontal cortex. There is significant collateral blood supply in the ACA territory. There are various stroke syndromes.Īnterior Cerebral Artery (ACA) Infarction With a good history and physical exam, we can localize the stroke. Typical causes of lacunar strokes include microemboli, fibrinoid necrosis secondary to vasculitis or hypertension, amyloid angiopathy, and hyaline arteriosclerosis. Lacunar strokes contribute up about 20% of all ischemic strokes and result from occlusion of the small penetrating branches of the middle cerebral artery, vertebral or basilar artery or the lenticulostriate vessels. The rest 20% of strokes are hemorrhagic in nature. Hemorrhagic etiologies can be from hypertension, aneurysm rupture, arteriovenous malformations, venous angiomas, bleeding due to illicit drugs like cocaine, hemorrhagic metastasis, amyloid angiopathy, and other obscure etiologies. Eventually, due to the excessive plaque build-up thrombotic strokes occur. In the older population, the risk of cardioembolic stroke increases mainly due to atrial fibrillation. One-third of the adults in the USA have elevated low-density lipoprotein (LDL), leading to plaque formation in the intracerebral vasculature. Every 10 mm Hg reduction in blood pressure is associated with a 1/3rd reduction in stroke risk in primary prevention. Lifestyle measures such as weight loss, salt restriction, taking more fruits and vegetables (such as the Mediterranean diet) are helpful in decreasing the blood pressure. Chronic uncontrolled hypertension causes small vessel strokes mainly in the internal capsule, thalamus, pons, and cerebellum. According to JNC8, the recommended blood pressure targets in patients with stroke should be less than 140/90 mm Hg. Hypertension is most prevalent in African-Americans and also occurs earlier in life. Of all the risk factors, hypertension is the most common modifiable risk factor for stroke. In general, the common risk factors for stroke include hypertension, diabetes, smoking, obesity, atrial fibrillation, and drug use. Ischemic etiologies can further be divided into embolic, thrombotic, and lacunar. The recent DAWN trial showed that one can extend the window for mechanical thrombectomy up to 24 hours in selected cases of large vessel occlusion. As acute stroke management is evolving rapidly, one must consider patients for intravenous tissue plasminogen activator (IV tPA) up to 4.5 hours and mechanical thrombectomy for up to 6 hours. As "time is brain", it is very important not to waste any time. ![]() In the acute setting, a quick history and examination to be performed. In the younger population, there are numerous causes of stroke including clotting disorders, carotid dissection, and illicit drug abuse. Hypertension is the leading cause of ischemic stroke. It is thus critical to recognize stroke early and treat it rapidly to prevent or minimize morbidity and mortality. Stroke is the leading cause of adult disability worldwide. Over the past several decades, the incidence of stroke and mortality is decreasing. In this discussion, we mainly confine to ischemic strokes. Approximately 85% of strokes are ischemic and rest are hemorrhagic. A stroke or cerebrovascular accident (CVA) is an acute compromise of the cerebral perfusion or vasculature. ![]()
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