Page 47 - Virtual Vascular Vol 3
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Vascular Lab Video: Carotid Duplex
Carotid Endarterectomy
• Transient ischaemic attack is a focal neurological deficit which
recovers spontaneously within 24 hours, whereas a neurological
symptoms of a stroke last more than 24 hours
• Carotid endarterectomy is indicated if the patient is symptomatic
and has significant carotid stenosis
• Investigations include carotid duplex, with or without CT or MR
angiogram
• CT / MRI brain is important pre-operatively to document ischaemic
changes and to rule out space occupying lesions
• ECG, Holter tape, or ECHOcardiogram are important if there is a
query of cardiac arrhythmia or emboli
• Patient should take anti-platelet agents (aspirin or clopidogrel) pre-
and post-operatively.
DUPLEX carotid ULTRASOUND of a patient with a 80% carotid stenosis. B-mode
image showed the large plaque. Additionl doppler study revealed a flow-velocity spectrum • Caroid endarterectomy can be performed under general or reginal
characteric of a high grade stenosis. Interanl carotid artery (ICA) Peak systolic velocity (PSV)
is one of the primary parameters for determination of the degree of stenosis. A PSV of anaesthesia.
<125 cm/s refers to stenosis <50%. PSV>230 cm/s denotes a significant stenosis of >70%.
Additional secondary parameters used include End diastolic vecocity (EDV) and ICA/CCA
PSV ratio. A EDV of >100 cm/s also characterises >70% stenosis.
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