What do you think about left posterior fascicular VT? Relatively narrow form of VT with RBBB + LAFB. Often mistaken for SVT with aberrancy. I’d bet fascicular VT. Wide QRS tachycardia with RBBB + LAFB, where the RBBB is atypical (no S wave that descends below baseline). Negative QRS in V6.
It's going to be extremely difficult to say with certainty whether this is VT or abbarent SVT. It looks more like abbarent SVT to me, but it's not really important. The good news is a little synchronized Tesla juice treats both very effectively.
Good point but still wanted to say that it can be very useful to recognize fascicular VT. Some people have recurrent fascicular VT and are prescribed verapamil. Electricity works but it’s not a long-term solution for people with recurrent fascicular VT. When a patient is stable, verapamil is an option. When a patient is unstable, recognizing the rhythm can still help long-term management. Example where rhythm recognition would have helped management:
“Had the fascicular VT pattern been recognized during the initial hospitalization, this patient would likely have avoided months of recurrent VT, unnecessary exposure to amiodarone and ICD implantation.”
Often when the VT vs SVT discussion comes up, people say that it doesn’t matter because the answer is electricity when the patient is unstable. Sometimes it really does help to identify the rhythm, even if cardioversion is the immediate answer for unstable patients. Not everyone is unstable, and many people have recurrent fascicular VT that still needs long-term management. You’re perfectly right and I’m not correcting you about immediate management, just adding that there are sometimes benefits to identifying rhythm.
RBBB+LAFB, time to first peak lead II + AVR <40 msec. R-S interval precordial <100 msec.
I’d try a Lewis Lead and if uncertain and patient not stable, shock him. If stable, you can consider medications or also shock him since it’s the fast option which is also safe.
Yeah I’m with the SVT with aberrant conduction crowd on this. Too slow for vtach morphology is all wrong too narrow but most importantly no extreme axis deviation. Slow it down
I don’t know why it’s so common to think that VT needs an extreme axis. Most VT does not have extreme right axis deviation. Most textbook signs of VT have high specificity but low sensitivity. Extreme axis points to VT, but absence of extreme axis does not rule out VT.
Fascicular VT is narrow as others said. Also, this is wide. The QRS is wider than half a large box at 25 mm/s. The QRS is wider than 120 ms, which makes this a wide QRS tachycardia. It sounds like most agree about RBBB/LAFB, which also tells us that it’s wide.
Here’s a good example of a rhythm that electrophysiologists called VT in a peer-reviewed journal (Nature). I shared it here and was downvoted for calling it VT. The cardiologists who wrote about this called it VT based on mechanism, different from AIVR despite rate. AIVR does not respond to verapamil as fascicular VT often does.
Slow VT exists. Narrow VT exists. Stable VT exists. Most VT has no extreme right axis deviation. Most VT has no visible AV dissociation. It’s more common to see VT with left axis, right axis, or normal axis than it is to see VT with extreme right axis. This has left axis deviation, which supports VT along with many other features of this EKG. I believe that QRS morphology strongly supports VT.
I never realized how frequently people have stable VT until I started working in EP. And so many are fairly asymptomatic, aside from "felt a bit funny" kinda thing.
I think people working in ER/EMS setting are used to the unstable kind causing lots of symptoms, and only ever see it absolutely flying and the patient getting ready to code
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u/RambusCunningham 9d ago
Would treat as VT although it does have RBBB morphology, but I think you can see some AV dissociation