need help with your account or subscription? click here to email us (or see the contact page)
join telegramNEW! discord
jump to exam page:
search for anything ⋅ score predictor (โ€œpredict me!โ€)

Retired NBME 24 Answers

nbme24/Block 4/Question#43 (reveal difficulty score)
A 72-year-old woman with coronary artery ...
Neointima formation in the right coronary stent ๐Ÿ” / ๐Ÿ“บ / ๐ŸŒณ / ๐Ÿ“–
tags: vascular

 Login (or register) to see more


 +39  upvote downvote
submitted by โˆ—xxabi(293)
get full access to all contentpick a username

Stent thrombosis vs re-stenosis. Stent thrombosis is an acute occlusion of a coronary artery stent, which often results in acute coronary syndrome. Can be prevented by dual antiplatelet therapy or drug-eluting stents. Re-stenosis is the gradual narrowing of the stent lumen due to neointimal proliferation, resulting in anginal symptoms.

get full access to all contentpick a username
sunshinesweetheart  so just to clarify - it's the "symptom-free for 3 months" that rules out thrombosis? +9
hpsbwz  It's moreso that at rest there's no changes, but during exercise there is. Like the pathophys of stable angina. +8
suckitnbme  I think it's more because of the 2-month history of PROGRESSIVE angina sx with exertion. This points to a chronic process rather than an acute event. +
alienfever  Drug-eluting stents prevent re-stenosis (rather than thrombosis) by releasing sirolimus which by blocking cell proliferation. +3



 +8  upvote downvote
submitted by โˆ—sweetmed(157)
get full access to all contentpick a username

Stent Restenosis occurs from scar tissue grows over stent causing โ€œneointimal hyperplasiaโ€ and narrowing, ischemia symptoms return Tx: prevent by using drig eluting stents eg. Sirolimus. Thrombosis Post stenosis is Acute, stent serves as nidus for thrombus formation usually 2/2 missing mediation. Tx: prevent by using dual antiplatelet treatment [aspirin+clopidogrel/ticagrelor]. After 1 year, endothelization of stent occurs and there is a lower risk of thrombus, Tx lowered to just aspirin.

get full access to all contentpick a username



 +5  upvote downvote
submitted by โˆ—hungrybox(1277)
get full access to all contentpick a username

Section on Endovascular Stenting from BIG ROBBINS (for people like me who need more context):

https://i.imgur.com/mhRrpwl.png

https://i.imgur.com/e9mO0Nz.png

get full access to all contentpick a username



 +2  upvote downvote
submitted by medschooler1(2)
get full access to all contentpick a username

I think the key here is that this patient already had a stent placed, was symptom free for a few months, and now has angina with exertion. Angina with exertion is describing "Stable angina", the angina is due to "demand ischemia". The most common cause of stable angina is atherosclerosis/atherosclerotic plaque build up and a very common adverse effect of stents is neointima formation/ forming a new plaque on the stent.... a thrombosis would cause angina at both rest and with exercise, due to "supply ischemia", and it would be more acute, not progressive like the question stem describes

get full access to all contentpick a username



 -1  upvote downvote
submitted by โˆ—an_improved_me(91)
get full access to all contentpick a username

Another thing to note: they could have made this question even trickier by asking whether or not you know which leads are associated with which arteries. This person had LAD and RCA stent placement. That means that they could have given you leads II, III, aVF (for RCA probs) or V1-V6, I, aVL (for LAD probs) and make you choose based on that.

This question was easier since all answers are regarding the RCA.

get full access to all contentpick a username



Must-See Comments from nbme24

seagull on Intestinal mucosa
tissue creep on Ask the roommate not to smoke in the apartment
drdoom on Adenosine
seagull on Increased serum testosterone concentration
atstillisafraud on Lamins
niboonsh on Only cookies are independently associated ...
atstillisafraud on Scar formation
lamhtu on Decreased adherence
drachenx on Damage to the rectovaginal septum
drdoom on Intestinal mucosa
azibird on Coronavirus
lsmarshall on Organic acid metabolism disorder
sympathetikey on Inhalant abuse
tea-cats-biscuits on Eosinophils

search for anything NEW!