Carotid Artery Disease Flashcards
What are the pathologies that can be found on a Duplex scan ?
- Stenosis.
- Carotid Body tumor
- Dissection
- aneurysma
- reversal of flow in the vertebral artery
- Arteritis
What are the elements of the work up for a patient with asymptomatic carotid stenosis ?
- History should be directed at identifying risk factors and prior ischemic events.
- Physical examination should note signs of cardiac and systemic vascular disease, including assessment of peripheral pulses, signs of prior clinical stroke.
- Carotid duplex
- CTA or MRA
Why do we not use Angiographie for diagnosis anymore ?
In the ACAS study, diagnostic Angios were associated with 1.2% risk of stroke.
What are the indications for CTA, MRA or Angio ?
- Symptoms dont correlate with the extent of carotid disease.
- The top of the plaque is not visualised.
- the vessel is extremely tortuous.
- The ipsilateral carotid is occluded.
- high carotid bifurcation
What is the Evidence for CEA ?
- VA trail (444 Patients)
significantly lower incidence of stroke and TIA in the surgery group 8% vs 20.6% - ACAS trial (1662 Patients) Surgery vs BMT (mit Aspirin)
significantly lower incidence of ipsilateral stroke and any perioperative stroke or death in the surgery group (5% vs 11%) - ACST (3120 Patients) immediate surgery vs deferral group
5 year risk reduction of all stroke or perioperative death in immediate CEA group vs deferral group (6.4 % vs. 11.8)
When is CEA indicated in asymptomatic patients ?
Stenosis of at least 60 % in arteriography or greater than 70% by carotid duplex.
What is the evidence about CEA vs. CAS ?
The Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) 2502 Patients
The CEA group had a higher incidence of periprocedural MI (2.3 vs 1.1)
The CAS group had a higher incidence of periprocedural stroke (4.1 vs. 2.3%)
There is lack of level I evidence comparing either CEA or CAS versus current best medical therapy.
What does BMT in asymptomatic Carotid stenosis include ?
Antiplatelets and agressive risk factor modification (Hypertension, Diabetes, Smoking cessation, Hyperlipidemia)
When is Dual anitplatelet therapy recommended ?
It is only reserved for patients with other reasons to be on them, such as recently placed coronary stents, who also additionally have asymptomatic carotid stenosis.
When is anticoagulation with warfarin or NOAKs recommended ?
Only if patients have other indications for anticoagulation.
Evidence : WARSS investigators performed a subgroup analysis on patients with stroke and large artery stenosis/occlusion and found no beneficial effect seen with warfarin over anti platelet agents.
Whats the benefit of statins ? Where is the evidence ?
- decreasing the incidence of ischemic stroke by 22% (SPARCL trial)
- Two separate meta-analysis showed a 20 to 22% ischemic stroke risk reduction with use of statin therapy.
- In diabetic patients 37% reduction in cardiovascular ischemic events and a 48% reduction in ischemic stroke (CARDS trial)
Whats the benefit of ACEIs and ARBs ? Where is the evidence ?
- Ramipril significantly lowered ischemic stroke, cardiovascular events, and death in high risk cardiovascular patients (HOPE trial).
- Losartan significantly reduced cardiovascular events (LIFE trial)
- Candesartan significantly reduced non fatal strokes (SCOPE trial)
- When ARBs were compared to Ca channel blockers, there was significant reduction in cardiovascular events especially ischemic stroke although both drugs equally lowered Blood pressure. (MOSES trial).
- 9% greater reduction in primary stroke in patients on ARBs compared to those on ACEIs (ONTARGET trial)
- Meta-analysis from six controlled trials comparing ARBs with ACEIs showed that ARBs are even superior in stroke reduction.
Whats the effect of controlling hypertension ?
- Decreasing BP by 10 mm Hg can decrease stroke incidence up to 33%.
- A meta-analysis of 7 RCTs showed a 24% reduction in stroke with the use of an antihypertensive.
- Systolic hypertension in elderly Program (SHEP) and Framingham heart study (FHS) showed that BP is directly related to the progression of carotid stenosis.
- Patients with ischemic stroke who received a combination of perindopril and indapamide showed a 28% risk reduction in recurrence ischemic events. (PROGRESS trial).
How do we protect diabetes patients with carotid atherosclerosis ?
- All patients should receive education on exercise, diet and glucose-lowering medication.
- All patients should be treated with statin regardless of baseline lipid levels as the CARDS trial has shown to reduce overall cardiovascular risk by 37% and stroke risk by 48%.
How do we help smokers ?
- current guidelines recommend that at every visit, the vascular physicians should ask his or her patients about history of smoking and their current smoking status.
- Smokers should be assisted with counselling and developing a plan for quitting that may include pharmacotherapy and/or referral to a smoking cessation program.
- In absence of contraindications pharmacologic therapies are strongly recommended.
What are medications that help smokers to quit ?
- Vareniclin.
- Bupropion.
- Nicotine Replacement Therapie
Whats the current guidelines take on statins and a target LDL ?
Previous guidelines recommended treating target LDL levels, however, this is no longer recommended, and statins are recommended for all patients with clinical atherosclerotic vascular disease.
How does smoking and diabetes affect the risk of ischemic stroke
The risk of ischemic stroke is increased 2-5 fold among patients with diabetes.
Smoking increases the risk of ischemic stroke by 25-50%