Embolic stroke

The term “embolic” was first suggested in 1854 by Virchow when he described a patient with occlusion of the brain arteries by clots that appeared to arise from the heart.

Embolic strokes occur when a blood clot or a piece of debris called plaque, which formed in another vessel in the body, and then breaks away and flows through the bloodstream blocking or occluding blood flow to the brain.

Embolic stroke is one of the most feared complications in atrial fibrillation patients and is the presenting symptom in 20–25% of cases. Up to 20% of strokes are related to atrial fibrillation, and atrial fibrillation is associated with more severe stroke outcomes.

Embolic strokes often begin instantly and in approximately 80% of patients reach their peak neurological deficits at or near onset.

In the majority of patients, emboli are thrombotic in nature and can be formed in an artery, cardiac chamber, heart valve, or vein. Less frequently, emboli may consist of non-thrombotic material, whereas in certain cases they may contain both thrombotic and non-thrombotic material,

The majority of cardiac thrombi are formed within a chamber (i.e., the left ventricle, the left atrial appendage, or the left atrium). In other patients, thrombi are formed on pathological cardiac valves.

Embolic stroke can turn into haemorrhagic stroke during cardiopulmonary bypass and heparinization, resulting in high morbidity and mortality.
Embolic stroke

Ischemic Stroke

Stroke is defined as abrupt onset of a focal neurological deficit lasting more than 24 hours. It is also called cerebrovascular accident (CVA) or apoplexy.

The majority of strokes occur when blood vessels to the brain become narrowed or clogged with fatty deposits called plaque. This cuts off blood flow to brain cells. A stroke caused by lack of blood reaching part of the brain is called an ischemic stroke.

Ischemic stroke is a heterogeneous disease and occurs due to a multitude of underlying pathologic processes. Around 85% of strokes are ischemic strokes, which happen when a blockage cuts off the blood supply to the brain. Brain cells start to die quickly after their blood supply is cut off, but this damage can be limited in many cases if treatment can be provided very quickly (within a few hours).

Some conditions can cause blood clots to form in the heart, which can then move through the bloodstream up into the brain. This is called an embolism.

Neurological symptoms and signs of an ischemic stroke usually appear suddenly, but less frequently, they occur in a progressive manner (stroke-in-progress). The typical presentation is the sudden onset of hemiparesis in an older person. Symptoms and signs vary depending on the location of the occlusion and the extent of the collateral flow.

Hypertension, carotid artery stenosis, atrial fibrillation and certain other cardiac conditions, ciga-rette smoking, diabetes mellitus, dyslipidemia, sickle cell disease, poor diet, physical inactivity, and obesity are well-established risk factors for ischemic stroke.

Ischemic Stroke