This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Cardioembolic stroke

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

Cardioembolic Stroke

One-third of strokes represent intracerebral or subarachnoid hemorrhage while two-thirds represent cerebral ischaemia (1)

Ischaemic stroke can result from a variety of causes such as atherosclerosis of the cerebral circulation, occlusion of cerebral small vessels, and cardiac embolism (1)

  • one-third of ischaemic strokes are of unclear cause, it is increasingly accepted that many of these cryptogenic strokes arise from a distant embolism rather than in-situ cerebrovascular disease, leading to the recent formulation of "embolic stroke of undetermined source" (ESUS) as a distinct target for investigation
  • ESUS working group investigators further proposed that the minimal stroke work-up should include brain neuroimaging with CT or MRI, 12-lead ECG, transthoracic echocardiography (TTE), 24 h Holter-ECG and imaging of both extracranial and intracranial vessels with any available imaging modality (DSA, MRA, CTA, or US)

Risk Factors for Cardioembolic Stroke

Atrial Fibrillation

  • AF is associated with a 3-5 fold increased risk of stroke
  • AF prevalence increases sharply from 0.1% among adults <55 years of age to almost 10% among those >80 years of age (4)

Systolic Heart Failure

  • regional stasis, a hypercoagulable state, and likely undiagnosed AF appear to predispose heart failure patients to cardiac thrombus (5)
    • these patients face at least a 3-fold higher risk of stroke than the general population (5)

Recent Myocardial Infarction

  • a long-established risk factor for ischaemic stroke - association appears causal because thrombi are often seen overlying areas of ventricular dyskinesis which may predispose to a thrombogenic stroke

Patent Foramen Ovale

  • affects approximately 25% of the general population
    • may serve as a passageway for paradoxical embolism from the venous to arterial circulation

Aortic Arch Atheroma

  • approximately 45% of individuals >= 45 years of age harbor atherosclerotic plaque in their aorta
    • been associated with stroke risk (7)
      • particulaly linked with stroke risk are large, ulcerated, non-calcified, or mobile atheromas (occur in approximately 8% of the population)

Prosthetic Heart Valves

  • meta-analysis of studies published between 1985 and 1992 found that patients with a mechanical valve faced a 4.0% annual risk of stroke, which decreased with the use of oral anticoagulation to 0.8% for aortic valves and 1.3% for mitral valve (8)

Other possible causes of thromboembolic stroke include:

  • infective endocarditis, dilated cardiomyopathy, papillary fibroelastoma, myxoma, and mitral calcification

Clinical Presentation

  • classically the presentaton is with the sudden onset of neurological deficits that are maximal at onset - this compares to strokes due to small-vessel occlusion (also known as lacunar strokes) or large-artery atherosclerosis may have a more stuttering course
    • cardiac embolism may lodge in distal arteries supplying the cerebral cortex while small-vessel occlusion affects subcortical tissue
      • cardioembolic stroke can be differentiated from lacunar stroke by cortical signs such as aphasia or visual field deficits
    • note though that clinical characteristics alone cannot reliably classify the underlying cause of ischaemic stroke

Investigation:

  • neuroimaging
    • majority of cardioembolic strokes involve lesions in a cortical territory
      • about half of cardioembolic strokes involve multiple cerebral arterial territories (i.e., both internal cerebral arteries or one internal cerebral artery as well as the basilar artery)
        • this distinguishes cardiac embolism from artery-to-artery embolism due to large-artery atherosclerosis in the cerebral circulation
        • in cardioembolic stroke vascular imaging of the intracranial circulation in the acute phase, such as with computed tomographic or magnetic resonance angiography, often reveals an abrupt vessel cut-off without significant atherosclerotic narrowing of the upstream vessel
  • ESUS working group investigators further proposed that the minimal stroke work-up should include brain neuroimaging with CT or MRI, 12-lead ECG, transthoracic echocardiography (TTE), 24 h Holter-ECG and imaging of both extracranial and intracranial vessels with any available imaging modality (DSA, MRA, CTA, or US) (3)
  • possible aetiologies of ESUS:
    • evidence has indicated that ESUS may often stem from subclinical atrial fibrillation (AF) which can be diagnosed with prolonged heart-rhythm monitoring (5)
    • emerging evidence indicates that a thrombogenic atrial substrate can lead to atrial thromboembolism even in the absence of AF
      • such an atrial cardiopathy may explain many cases of ESUS, and oral anticoagulant drugs may prove to reduce stroke risk from atrial cardiopathy given its parallels to AF
      • improved imaging of ventricular thrombus plus the availability of NOAC drugs may lead to better prevention of stroke from acute myocardial infarction and heart failure

Reference:

  • Krishnamurthi RV et al. Global Burden of Diseases IRFS and Group GBDSE. Global and regional burden of first-ever ischaemic and haemorrhagic stroke during 1990-2010: findings from the Global Burden of Disease Study 2010. Lancet Glob Health. 2013; 1:e259-281.
  • Adams HP Jr et al Classification of subtype of acute ischaemic stroke. Definitions for use in a multicenter clinical trial. TOAST. Trial of Org 10172 in Acute Stroke Treatment. Stroke. 1993; 24:35-41.
  • Hart RG et al. Embolic strokes of undetermined source: the case for a new clinical construct. Lancet Neurol. 2014 Apr; 13(4):429-38
  • Wolf PA, Abbott RD and Kannel WB. Atrial fibrillation as an independent risk factor for stroke: the Framingham Study. Stroke 1991; 22: 983-988
  • Lovett JK, Coull AJ and Rothwell PM. Early risk of recurrence by subtype of ischemic stroke in population-based incidence studies. Neurology 2004; 62: 569-573
  • Kronzon I, Tunick PA. Aortic Atherosclerotic Disease and Stroke. Circulation. 2006; 114:63-75.
  • Cannegieter SC, Rosendaal FR, Briet E. Thromboembolic and bleeding complications in patients with mechanical heart valve prostheses. Circulation. 1994; 89:635-641
  • Ringelstein EB et al. Computed tomographic patterns of proven embolic brain infarctions. Ann Neurol. 1989; 26:759-765

Create an account to add page annotations

Add information to this page that would be handy to have on hand during a consultation, such as a web address or phone number. This information will always be displayed when you visit this page

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.

Connect

Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.