From the Guidelines
The workup for a suspected right carotid artery blockage involves immediate initiation of aspirin 325mg orally and/or intravenous heparin with a bolus dose of 80 units/kg followed by an infusion of 18 units/kg/hour, as well as a non-contrast computed tomography (CT) scan of the head to rule out hemorrhagic stroke, followed by a CT angiogram (CTA) of the neck and head to confirm the diagnosis and assess the degree of stenosis 1.
Key Diagnostic Steps
- Brain imaging: A non-contrast CT scan of the head should be performed to rule out hemorrhagic stroke 1.
- Non-invasive vascular imaging: A CT angiogram (CTA) of the neck and head should be performed to confirm the diagnosis and assess the degree of stenosis 1.
- Alternative diagnostic modalities: If CTA is not available, a magnetic resonance angiogram (MRA) or digital subtraction angiogram (DSA) may be considered as alternative diagnostic modalities 1.
- Laboratory investigations: Initial bloodwork, including hematology, electrolytes, coagulation, renal function, random glucose, and troponin, should be routinely considered as part of the initial evaluation 1.
- ECG: A 12-lead ECG should be performed to assess cardiac rhythm and identify atrial fibrillation or flutter or evidence of structural heart disease 1.
Additional Considerations
- ECG monitoring: ECG monitoring for more than 24 hours is recommended as part of the initial stroke work-up to detect paroxysmal atrial fibrillation in patients who would be potential candidates for anticoagulant therapy 1.
- Echocardiography: Echocardiography may be considered to search for a source of cardiogenic embolism when extracranial or intracranial cerebrovascular disease is not severe enough to account for neurological symptoms of suspected ischemic origin 1.
From the Research
Workup for Right Carotid Artery Blockage
The workup for right carotid artery blockage typically involves imaging tests to evaluate the degree of stenosis and assess the risk of stroke. The following are some of the key steps involved in the workup:
- Imaging tests: Computed Tomography Angiography (CTA) is a commonly used imaging test for evaluating carotid artery stenosis 2. CTA has a high sensitivity and high negative predictive value for carotid disease, making it an excellent screening test for internal carotid artery stenosis.
- Diagnostic criteria: The degree of stenosis is typically measured using the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method 2, 3. However, some studies have suggested that alternative markers such as intraluminal thrombus, maximum soft plaque thickness, and the rim sign may be more highly associated with ischemic stroke than stenosis alone 4.
- Cost-effectiveness: The cost-effectiveness of CTA in the workup of patients with suspected carotid artery stenosis has been evaluated in several studies 5. The results suggest that CTA is a cost-effective strategy, particularly when used in combination with duplex ultrasonography and surgery for patients with 70%-99% stenoses.
Imaging Tests
The following imaging tests may be used to evaluate right carotid artery blockage:
- CTA: CTA is a non-invasive imaging test that uses X-rays and contrast material to produce detailed images of the carotid arteries 2, 3.
- Magnetic Resonance Angiography (MRA): MRA is another non-invasive imaging test that uses magnetic fields and contrast material to produce detailed images of the carotid arteries 6.
- Duplex Ultrasonography: Duplex ultrasonography is a non-invasive imaging test that uses sound waves to produce images of the carotid arteries and evaluate blood flow 5.
Treatment
The treatment of right carotid artery blockage depends on the degree of stenosis and the patient's overall health. The following are some of the treatment options:
- Carotid Endarterectomy: Carotid endarterectomy is a surgical procedure that involves removing plaque and other debris from the carotid artery to improve blood flow 2, 5.
- Transcarotid Artery Revascularization: Transcarotid artery revascularization is a minimally invasive procedure that involves using a catheter to insert a stent into the carotid artery to improve blood flow 3.