(This was initially published on blog.5minsono.com on May 21, 2018)
Ultrasound (US) is an extremely valuable tool in the evaluation of patients with suspected acute pulmonary embolism (aPE). I am planning on writing a few posts on what I think is the best way to utilize US in the evaluation of PE, and today I’m going to talk about the McConnell’s sign. The McConnell’s sign is defined as relative hyperkinesis of the apex of the right ventricle (RV) relative to the RV free wall in the setting of RV strain. (aka enlargement).1
This finding is thought is often used to tell if a patient with an aPE has right heart strain due to massive or submassive PE. The McConnell sign was first mentioned in 1996 and that article reported that the sign had 94% specificity for aPE 1. As should be the case with anything in medicine, there have subsequently been multiple studies that attempted to reproduce the findings of the original study. The subsequent studies were a bit of a mixed bag. Some studies seems to show a pretty low specificity and others seems to show a high specificity.
As you can see, probably the best way to use McConnell’s sign is to look for it when you have a patient with known aPE or in patients in whom you have a high suspicion of aPE. If you look at everybody who has an echo, McConnell’s sign isn’t that useful (since chronic pulmonary HTN and RV MI’s can also have it).
Check out this podcast where Mike Mallin, Ben Smith and I talk about it more in depth.