Page 47 - Virtual Vascular Vol 3
P. 47

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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