Wolff Parkinson White Syndrome is a rare cardiac conduction disorder that affects less than 3% of the human population.
In fifteen years as a paramedic, I’ve seen it twice. Both of those times, the victim was over 40 years of age before being diagnosed.
Weird, that.
The first victim was a 52-year-old woman who had gone for years without an explanation for her frequent syncopal episodes. CT scans, ECGs, MRIs, a number of occasions where she wore a Holter monitor for 48 hours or more… all of them revealed nothing other than her baseline rhythm of atrial fibrillation, right up to the day she suffered one of those syncopal episodes while attached to my cardiac monitor.
One cardioversion attempt later, she was back to good old atrial fib, none the worse for wear. My partner and her husband had to change their shorts, but I, stalwart EMS professional that I am, remained stoic and utterly unflappable the entire time.
Rumors that I squealed like a little bitch and forgot to use the gel conductive pads before shocking her are entirely unfounded. Srsly.
But in the fourteen years and untold number of patients since, I’ve never encountered another case until last week, at least not when there was an active problem that required intervention. Of course, there is also the possibility that I saw a lot of it early in my career and was too ignorant to recognize it for what it was.
During those years, I have formed a few opinions about management of abnormal heart rates in the field:
- Hemodynamically unstable rate problems are best treated with electricity, not those selective cardiotoxins we call antiarrhythmics.
- Conversely, hemodynamically stable tachycardias are best treated with diesel fuel and tincture of time, and perhaps PFT Therapy.
- Instability in any patient with a rate problem has less to do with the actual number on your monitor than how your particular patient is dealing with it. Some people with a rate of 160 are infinitely sicker than the guy with a rate of 220.
Most of the people I use adenosine on could easily wait another five minutes until they arrive at the ER. Honestly, I push it to placate the ER doctors and nurses. Ditto for Cardizem. Oh, it’s clinically indicated every time I give it, but the patient is rarely so sick that “watch and wait” could not be considered a viable alternative. I rarely give lidocaine or amiodarone outside of arrest situations because most ventricular tachycardias are better treated with cardioversion.
Hence, the therapeutic electrocutions. If a patient is so sick that they have to be treated in the field, nine times out of ten, that treatment oughta be transcutaneous pacing or synchronized cardioversion.
To a great degree, I think a lot of my colleagues have it backwards; they think nothing of pushing selective cardiotoxins antiarrhythmics, yet have an almost mythical fear and loathing of electrical therapy.
Me, I’m just the opposite. There have been times when I’ve unsuccessfully tried pacing or cardioversion, but I can safely say that, if it had an undesired effect, I’ve never had to thumb through a Nursing Drug Reference to find out how long it takes someone’s liver and kidneys to metabolize and excrete a jolt of electrical current.
So flash forward to last week, when I met my second WPW patient. She’d been diagnosed five years prior, but had never had a tachycardic episode prior to that night. When it hit her, she promptly passed out. She came to a few seconds later, complaining of 10/10 chest pain and difficulty breathing. Her BP was okay at 112/64, but she looked like crap…
… which, to an experienced clinician, is an even more reliable indicator of instability than the blood pressure.
She was lethargic and weak, but coherent, so I was able to get a pretty fair history as I attached the cardiac monitor and Rookie Partner got vital signs.
So when I had all my ducks in a row, I lit her up like a Christmas tree:
A few observations from the event and the war stories afterwards:
- When a patient tells you, “Oh, no nasal sprays! I’ll throw up!”, it’s best to believe her and hold off on the intranasal Versed. Better to spend an extra couple of minutes to find a vein and give it intravenously.
- Synchronized cardioversion works much better if you actually hook the hands-free pads to the patient cable. Plus, you get the added benefit of not looking like a goober. But it gives your partner a cool war story of his own, and he has so few, the poor kid…
- A forty year old woman, when hit with 100 Joules of current, will make a sound exactly like Macho Man Randy Savage. For the past week, RP and I have been giggling like fiends and saying “Oooooh yeah, snap into a Slim Jim!”
- Most of my colleagues, when faced with the same patient, would have given her adenosine or Cardizem. And quite possibly have killed her in doing so. One does not suppress the normal conduction system when the patient has an abnormal accessory pathway that is much faster, kiddies. That’s a helpful tip from your Uncle Ambulance Driver.
"I lit her up like a Christmas Tree" <– that there had me laughing so hard I cried. It's all your fault my neighbours think I'm nuts AD.
Well done, AD.
Rhythm looks like 1:1 atrial flutter.
Cardizem or adenosine might well have killed her indeed.
We've recently pulled Cardizem off the truck, and we don't allow adenosine for heart rates > 250 (for just this reason).
Tom B.
“Rhythm looks like 1:1 atrial flutter.”
I was leaning that way myself, Tom, but I’ll gladly take the word of the cardiology guru himself. *grin*
They didn’t quite look like Delta waves to me, but given her history, I knew that conventional antiarrhythmics weren’t an option anyway.
And like I said earlier, I’m a shocker, not a doser.
Thanks, Uncle!
(Why are you buying me ice cream, again?)
Good post AD,
First off I wanted to say welcome to the paramedicine blog, I noticed your author acceptance today.
Secondly, Good catch. Its stories like this that make me always double check my “fast heart” patients . The idea of giving Cardizem or Adenocard to a WPW patient, is a scary one. I emphatically agree with your treatment methods. My drug of choice for unstable tachyarrythmias is Versed, right before the zap. The contraindications are much less detrimental.
No audio? I feel cheated.
There should be an olfactory component to this post, too. Or were you just kidding about the gel?
No precordial thump?
Nice post. Welcome to the <>Group W Bench<>.
I keep trying to explain about sedation and transport, but people are brainwashed with the antiarrhythmics. Apparently, brainwashing is a side effect ignored by the FDA.
AD –
That's a good point with regard to the delta waves. This could be an orthdromic AVRT. Sometimes you need an EP study to know for sure.
I'd like to clarify something with regard to the rate. At the time of cardioversion, the R-R interval was approx 6.5 small blocks (rate of about 230). In the rhythm strip, there are a couple of R-R intervals right at 6 small blocks (rate of 250).
This is particularly important with irregular tachycardias. If the shortest R-R interval is 6 small blocks (or even close) then you should suspect an accessory pathway and lay off the drugs!
I'm with you 100% with regard to prehospital antiarrhythmics.
My sister's boyfriend was recently experiencing palpitations and the Holter monitor revealed paroxysmal atrial flutter. He's following up with an EP.
While researching his condition I found some interesting comments that I'd like to share.
"[T]he anatomy of the atria is very complex, being derived from regions with trabeculated myocardium (free wall of right and left atrium), multiple orifices (superior and inferior vena cava), coronary sinus, ostia of the pulmonary veins, the mitral and tricuspid annulae, and the region of the fossa ovalis, which is multilayered. These abnormal regions, in and of themselves, produce abnormalities of propagation in the absence of differing electrophysiologic properties. However, to complicate matters, the cellular electrophysiology of the various parts of the atrial tissue vary [...] The atria are also markedly influenced by cholenergic as well as sympathetic innervation [...] Thus, the atria have anatomic, electrophysiologic, and neurological heterogeneity to such an extent that it is surprising why everybody doesn't have atrial arrhythmias."
Clinical Cardiac Electrophysiology: Techniques and Interpretations, Third Edition, Mark E. Josephson, 2002 Lippincott Williams & Wilkins, p. 273
Tom, would orthodromic vs antidromic conduction display differently on an ECG. Just the delta waves or widened QRS?
I am going to do some research but just wondered if I could get the quick answer from you.
Adam –
With orthodromic circus movement tachycardia the reentry circuit goes down the AV node and up the accessory pathway, so the QRS morphology is typically normal.
With antidromic circus movement tachycardia the reentry circuit is down the accessory pathway and up the AV node, so the QRS is generally wide and bizarre.
At least, that’s my understanding!
Tom
I have nothing to add medically, but my daughter had/has? WPW syndrome, which is very rare in people under 35. It is not supposed to be genetic, but my nephew had it as an infant.
At age 10 we were visiting the ER every other week with heart rates >275. We never actually had an ambulance transport her, but it irritated me greatly when they wouldn't take the readouts from the paramedics as "evidence" of a tachycardiac (sp?) event. She had to suffer for almost a year with the shorter lasting episodes (less than 1/2 hour).
The ER never used electric shock, even after hours of being unable to get her heart beats to slow down. Always meds.
After almost a year of irregular episodes, she finally had surgery and hasn't had an episode since! Outpatient heart "surgery" still blows my mind.
Like I said nothing to do with your post, but I just felt like sharing. Thanks for the repeated laughs over the last few months since I've been reading your blog.
Mary in Texas
http://marythemom-mayhem.blogspot.com/
Wow you guys are smart!!! I just do medical billing… Still wish I would of strived to be more.
Nicole
Re: Tom’s comment on orthodromic vs antidromic circus movement tachycardia, that was always my understanding as well.
Antegrade conduction through normal pathways with the reentry circuit being retrograde through the Kent bundle will produce normal QRS complexes, as is the case with orthodromic reentry tachycardia.
If the opposite is true, with antegrade conduction going through the Kent bundle, you should see Delta waves or bizarre QRS morphology, as is the case with antidromic reentry tachycardia.
I recall a patient once, presented in fairly stable SVT.
She had WPW, so Ca++ Blockers were out.
She had asthma, so B-Blockers were out.
She was on Persantine, so Adenosine was out.
Ended up giving her a safe, but somewhat expeditious, ride to the ER.
*shrug*
I LOVED this. I laughed and I learned.
I’m glad I read the comments on this one. I was starting to doubt myself or maybe it was just my resolution, because I couldn’t make out any delta waves, but I agree on the electricity over chemical with unstable tachycardia’s.
BRM
Yeah, I ain’t real sure about the delta waves, but I think that you do see some up-sloping. Us EC docs have the luxury of twelve lead EKGs. That said, a flutter usually produces a flutter rate of about 300, with ventricular rates of 300, 150, 100, or 75, depending on the conduction rate. A 1:1 conduction will be close to 300, whereas a 1:2 conduction will be close to 150. Adenosine/Adenocard is contraindicated in WPW, so *anytime* I see a narrow tachycardia with any other rate than those listed (I am exempting a-fib with RVR), I usually avoid adenosine in favor of procainimide or lidocaine, just to be on the safe side.
Electricity id for hemodynamically unstable patients which I define as those with an altered mental status, more than a particular number on their vitals.
doc Russia -
The flutter rate is often around 300, but it's not a hard and fast rule. In the absence of antiarrhythmic medications, flutter rates correlate with right atrial cross sectional area englargement.
Flutter rates < 250 are considered "slow" but still within the range of possibility. In one study I just read the mean flutter rate was 283 in the "normal" flutter group and 227 in the "slow" flutter group.
I've seen many cases of 1:1 atrial flutter with ventricular rates < 250. For example, this < HREF="http://www.facebook.com/photo.php?pid=1667661&l=0d5c0629f8&id=578352475" REL="nofollow">case<> I posted to the Cardiology & Electrocardiography (ECG, EKG) Experts group in Facebook.
For AD's case, I thought the ECG had the general appearance of QRS complexes superimposed on flutter waves (more so before I enlarged the image).
Incidentally, 12 lead ECG monitors are fairly common in the prehospital setting, at least in the U.S.
Tom
Dude, I want you (or someone like you who actually *thinks*) picking me up if I ever need another ride.
interesting….I’ve been dealing with a bit of tachy myself, only while exercising (200-240 bpm at a slow jog). Saw the cardiologist last week who wants to do a stress test to rule out an accessory pathway. I had a normal resting ekg with no delta wave problems….isn’t that contradictory to an accessory pathway, or is it possible it won’t show up until my heart rate rises? So much to learn!
CuriousEMT
Anonymous, there are other accessory pathways besides Kent fibers, that terminate in other parts of the conduction system.
James fibers, responsible for Lown Ganong Levine Syndrome, arise in the atria and have their terminus near the His Bundle. Mahaim fibers are less well understood than Kent or James fibers, but it is believed that they arise in and around the AV Node and His Bundle and have their terminus in the ventricular myocardium.
In Lown-Ganong-Levine preexcitation, QRS morphology is typically normal, without the characteristic Delta wave of WPW. There is, however, a markedly shortened PR interval.
I couldn’t give you much information about Mahaim fibers – they’re a hole in my cardiology knowledge. Maybe Tom B. will chime in here and enlighten both of us.
I’m a fan of Deisel Treatment. If a get a heart rate over 150 it had better come with bold SVT letters attatched to it before I’ll give adenosine. Of course, the fact that Providence has a hospital on every corner, and that I spent ten years trying to figure out my own syncopal episodes before catching SVT in my own heart, subsequently treated with radiofrequency ablation makes me biased.
Adenosine feel weird. Trust me. Didn’t touch mt SVT, I stayed ay 220 for six hours before it stopped.
HERE HERE!!
Very well said Sir. +10 point for you. http://www.ems-uncovered.blogspot.com
Thanks for the vote of confidence, AD, but I claim no special expertise when it comes to classifying the preexcitation syndromes.
According to Josephson, they’re moving away from the eponyms Kent fibers, James fibers, and Manhaim fibers in favor of a new classification system proposed by the European Study Group for Preexcitation.
I’d transcribe it for you, but it’s long, complicated, and over my head.
Tom B.
Okay, maybe not so new!
Anderson RH, Becker AE, Brechenmacher C, et al. Ventricular preexcitation – A proposed nomenclature for its substrates. Ear J Cardiol 1975;3:27.
Tom
More geekery please.
This post is worth a link. I learned, or re-learned I hope, some things that I probably had forgotten. Thanks for the reminder.
I use adenosine every so often, but I can’t remember a time where it actually worked. Every bit of Edison medicine I’ve done has been very successful, excluding defibrillation.
I am in the 3% of the population
I was dx’d w/ WPW when i was in my 2nd year of RN school. I went to give blood and they wouldn’t accept me b/c my BP was ~ 160/110. And i was 20!!
Diagnostic after diagnostic failed to reveal the source of the HTN, but an ECG at the cardiologists office revealed WPW!!
I had a cardiac ablation. A month later (to the day!) i had my first true tachy episode (170s! … Felt like a palpitation that wouldn’t stop) and had another EPS, minus the ablation b/c they couldn’t find the source. I’ve been good ever since … As far as i know … I suppose i’m due for another ECG …
I’m always amazed when i read about how rare this is, b/c i had/have it.
This has been one of the most fruitful readings of my life…thanks for the post.
It is difficult to always be under pressure of performance as it is always about life and death.And you guys do an incredible job of driving us through emergency and gifting us lives often…and we never turn back and says thanks.
All that you go through feeling others pains and anxieties and trauma is great.You do a silent yet great job…