🚧Calling all @CardioNerds! What is this sign on EKG called? #CNshowmeasign 🚧
Crochetage sign is a notch on the apex of R waves in the inferior leads. It can be associated with ostium secundum ASDs.
It is a result of delayed depolarization of the right ventricle because of L to R shunt. This is why ostium secundum ASDs are also associated with:
🚦Right axis deviation
🚦Incomplete RBBB
⚡️ Sens/spec: 73.1%/92.6% (when in 1 inferior lead); 27.8%/100% (when in all inferior leads). Increased specificity when associated with incomplete RBBB.
⚡️ Correlated with greater anatomic defect or greater L to R shunt.
⚡️ Sens/spec for dx PFO in cryptogenic stroke: 36%/91%.
⏳ "Crochetage" = French for "notching"
⌛️ First described 1959 by Rodriguez-Alvarez et al in 11 patients with ostium secundum ASDs.
References:
pubmed.ncbi.nlm.nih.gov/8613618/
casereports.bmj.com/content/2016/b…
Thank you to my mentor @jcurrier17 for teaching me about EKGs seen in ASDs and inspiring this med ed project.
#CNshowmeasign brought to you by @PatrickZakka and @a_h_ghoneem.
Special thank you to @TDonisan (for the amazing graphics) and @AmitGoyalMD @Dr_DanMD for reviewing.
If there are any other signs you would like us to tackle, put them in the comments and let us know what to do next!
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