Mehl. Carotid artery stenosis Flashcards
Mehl. Carotid artery stenosis. caused by?
Caused by atherosclerosis.
Mehl. Carotid artery stenosis. biggest risk factor?
HTN biggest risk factor for atherosclerosis specifically of the carotids (strong systolic impulse pounds the carotidsàendothelial damageà atheromatous plaque formation).
Mehl. Carotid artery stenosis. Carotid bruit only seen in about 25% of Qs. Don’t rely on this as crutch.
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Mehl. Carotid artery stenosis.
Vignette will give a stroke, TIA, or retinal artery occlusion in the setting of a patient with HTN.àYou have to be able to make the association that a plaque from one of the carotids has launched off, since HTN = incr. risk
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Mehl. Carotid artery stenosis. USMLE will then ask for management (2CK only): best next step in Dx?
Do carotid duplex ultrasonography as next best step in diagnosis to look for degree of occlusion. I’ve never seen carotid angiography as a correct answer on NBME exams.
Mehl. Carotid artery stenosis. If occlusion >70% symptomatic, or >80% asymptomatic, then do what?
endarterectomy
Mehl. Carotid artery stenosis. what is ,,symptomatic”?
stroke, TIA, or retinal artery occlusion.
A mere bruit is not a symptom; that is a sign.
Mehl. Carotid artery stenosis.
If under these thresholds (occlusion >70% symptomatic, or >80% asymptomatic), do medical management only, which requires a triad of???3
1) statin; 2) ACEi or ARB; and 3) anti-platelet therapy.
Mehl. Carotid artery stenosis.
The USMLE will not force you to choose between low- and high-potency statins.
USMLE tends to list lisinopril as their favorite ACEi for HTN control.
It’s to my observation aspirin alone is sufficient on NBME exams for anti- platelet therapy, even though in real life patient can receive either aspirin alone; the combo of aspirin + dipyridamole; or clopidogrel alone.
Mehl. Carotid artery stenosis.
- USMLE will not give borderline carotid occlusion thresholds – i.e., they’ll say either 30% or 90%. If they list the % as low, look at the vignette for the drugs they list the patient on. Sometimes they’ll show the patient is already on statin, lisinopril, and aspirin, and then the answer is just????
“continue current regimen.”
I have once seen “add clopidogrel” as a wrong answer in this setting, which makes sense, since the combo of aspirin + clopidogrel is never given anyway.
Mehl. Carotid artery stenosis.
Sometimes they will give you a low carotid occlusion % + say the patient is on 2 of 3 drugs in the triad, and then the answer is just ???
“add aspirin,” or “add statin,” or “add lisinopril.”
Mehl. Carotid artery stenosis.
If the vignette doesn’t mention elevated BP but says you have some random dude over 50 with a stroke, TIA, or retinal artery occlusion, the next best step is???
carotid ultrasonography to look for carotid stenosis. In other words, it is assumed the patient has a carotid plaque in this setting.
Mehl. Carotid artery stenosis. If the vignette gives patient with episodes of unexplained syncope or light-headedness, but not stroke, TIA, or retinal artery occlusion, then the next best step is????
ECG, followed by Holter monitor, looking for atrial fibrillation (AF causes LA mural thrombus that launched off to brain/eye).
Mehl. Carotid artery stenosis.
- The triad of 1) statin; 2) ACEi or ARB; and 3) anti-platelet therapy is also done for what disease?
peripheral vascular disease unrelated to carotid stenosis (i.e., if a patient has intermittent claudication)
Mehl. Carotid artery stenosis.
Stroke, TIA, or retinal artery occlusion, if they don’t mention HTN, but they mention an abdominal bruit, WHAT TO DO?
Carotid duplex ultrasound.
The implication is that the bruit in the abdomen could be a AAA or RAS, where atherosclerosis in one location means atherosclerosis everywhere, so the patient likely has carotid stenosis by extension. They once again need not mention carotid bruit; apparently it is not a sensitive finding (i.e., we cannot rule-out occlusion just because we don’t hear it).
