Ambulance Driver Files A Day in the Life | Kelly Grayson
In case you haven’t read them, the EKG Yoda, Tom Bouthillet, has a series on narrow complex tachycardias on his Prehospital 12-Lead ECG blog. If you’re interested in cardiology, you should definitely give them a read. Go ahead, I’ll wait.
Narrow Complex Tachycardias: Part 1
Other than the rare zebra, there’s a reason I don’t post many cardiology case studies here on my blog, and that’s because I see no point in the exercise if there is already someone who does it better. Tom is that guy.
In his first installment in the series, Tom offers his opinion on the terminology we so blithely throw around regarding tachycardias:
I’ve come to dislike the term “SVT” (supraventricular tachycardia).
In the first place, it’s not an arrhythmia. It’s an umbrella term that covers a group of arrhythmias which require the AV node for their maintenance.
Most importantly, it includes sinus tachycardia!
For some reason, this is a difficult concept for many clinicians to grasp, partly because of myths passed on from generation to generation.
For example, my least favorite of all.
“If the rate is 150 or greater, it’s SVT.”
Forgive me, but what in the Wide World of Sports is that supposed to mean?
Does it mean that junctional tachycardia at a rate of 149 is not SVT?
I think the term “SVT” is less helpful than the term “narrow complex tachycardia” for figuring out a differential diagnosis.
Word to ya mutha, Tom.
Using a blanket term like “SVT” is akin to using the word “car,” when you actually mean “red Ferrari 308 GTS.”
That red Ferrari is akin to a Yugo only in the fact that they both have four wheels and seats, and WPW is akin to atrial tachycardia only in the fact that they’re both faster than 100 beats per minute.
Otherwise, they’re very different critters. You’re not going to use the same tools to treat them, no more than you’d use the guy at Jiffy Lube to do the warranty work on your Ferrari.