From the Guidelines
No, embolic stroke and ischemic stroke are not synonyms, but rather embolic stroke is a subtype of ischemic stroke. Ischemic stroke is the broader category that occurs when blood flow to the brain is blocked, causing brain tissue damage due to lack of oxygen and nutrients. This category accounts for about 87% of all strokes. Embolic stroke specifically refers to an ischemic stroke caused by an embolus—a traveling clot or debris that forms elsewhere in the body (often in the heart or large arteries) and travels through the bloodstream until it lodges in a brain artery, as classified in the guidelines for prevention of stroke in patients with ischemic stroke or transient ischemic attack 1.
The distinction between different types of ischemic strokes, including embolic stroke, is crucial for diagnosis, treatment, and prevention. According to the guidelines, ischemic stroke is classified into various categories according to the presumed mechanism of the focal brain injury and the type and localization of the vascular lesion, including large-artery atherosclerotic infarction, embolism from a cardiac source, small-vessel disease, and others 1.
Key points to consider include:
- Ischemic stroke classification is based on the mechanism of focal brain injury and vascular lesion type and localization.
- Embolic stroke is caused by an embolus originating from elsewhere in the body, such as the heart or large arteries.
- Understanding the subtype of ischemic stroke, such as embolic versus thrombotic, is vital for targeted treatment and prevention strategies, as embolic strokes may require investigation into the source of the embolus, like atrial fibrillation or heart valve disease 1.
In clinical practice, recognizing embolic stroke as a subtype of ischemic stroke allows for more precise management and potentially improves outcomes by addressing the specific cause of the stroke, whether it be cardiac in origin or due to other factors 1.
From the Research
Definition and Classification of Stroke
- Stroke is a clinically defined syndrome of acute, focal neurological deficit attributed to vascular injury (infarction, haemorrhage) of the central nervous system 2.
- Most (85%) strokes are ischemic, predominantly caused by small vessel arteriolosclerosis, cardioembolism, and large artery athero-thromboembolism 2.
Embolic Stroke and Ischemic Stroke
- Embolic stroke of undetermined source (ESUS) designates patients with nonlacunar cryptogenic ischemic strokes in whom embolism is the likely stroke mechanism 3.
- Embolic stroke is a subtype of ischemic stroke, and it is not a synonym for ischemic stroke, but rather a specific type of ischemic stroke caused by an embolus 3, 4.
- Ischemic stroke represents one of the leading causes of death and disability, and it can be caused by a wide range of risk factors, disease processes, and mechanisms, including embolism 5, 6.
Key Differences and Similarities
- Embolic strokes are more likely to be severe and have a higher risk of mortality compared to thrombotic strokes 4.
- The risk of having a more severe stroke is higher among embolic stroke patients compared to thrombotic stroke patients, with a step-wise increase for embolic stroke patients when moving from mild to very severe strokes 4.
- Both embolic and ischemic strokes can be treated with antiplatelet and anticoagulant therapies, although the specific treatment approach may vary depending on the underlying cause and severity of the stroke 5, 6.