V-Tach With a Pulse

[lightsandsirens5]

So, what would you have done here?

75 yom was seen by family to "pass out" and fall backwards off of a bar stool, landing on his back. According to his wife, he began coughing uncontrollably for about 10 seconds before hand and was completely unresponsive for 30 seconds to a minute on the floor. Pt was not eating anything, at the time.

Upon our arrival, pt presents with: A: Patent. B: Regular, Non labored. C: Strong radial pulse @ 60/min. LOC: Responds to verbal. Pupils: PEARL @ approx 4mm. Skin: Warm, very pale on neck and face, dry. Extremities pink c cap refil <2 sec. No bleeding noted. HEENT: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Neck: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Back: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Chest: Repeatedly denies chest pain. Pt has a pacer/defib implanted on L upper chest. Heart: Three lead shows a ventricular paced rhythm @60 bpm. Pt does not believe internal defib went off. Abd: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Pelvis: Intact. Denies pain. Able to ambulate s assist. Neuro: GCS=15. Pt is CAOx3/4 (does not remember what happened). States he feels "just fine."

Initial vitals:
B/P: 132/78
PR: 60
RR: 14
SPO2: 98% on RA
D-Stick: 130
Monitor shows ventricular pacer with good capture

Started a line, loaded him on the gurney, and began to take him out to the truck. Load him in the truck and go to take another set of vitals:
B/P: 148/90
PR: 130
RR: 14
SPO2: 99% on RA
(I rechecked the pulse twice and got 150 the second time and 146 the third time.) We have been in the truck all of 15 seconds at this point, so I haul the monitor out from behind the head of the gurney and take a look. V-Tach @ 150. Look at pt, look at monitor, look at pt, look at monitor.......Pt is fine. Recheck vitals and get the same readings as before. In fact, the pt is no longer pale, and his skin color looks great.

About 5 minutes into the transport he converts back into his paced rhythm @ 60, at which point his vitals go back to like the first set, and he becomes pale again. A minuted or so later on, he goes back into V-Tach and pinks up, BP comes up. Did that several times all the way in to the ER.

What on earth is going on??? As a medic student I am racking my brain for what is up, but keep drawing blanks.

 

[izibo]

Are you sure this wasn't a runaway pacemaker? I have seen this exact situation, including the fact that the patient felt better and looked at me funny when I seemed concerned. It wasn't until I really looked closely on a printout that I saw the pacer spikes.

 

[STXmedic]

You don't have the printout, do you?

 

[lightsandsirens5]

I suppose it could have been a runaway pacemaker. Didn't think of that one.

No I don't have the printout unfortunately, but it looked like classic v-tach to me. Although I suppose that with a ventricular pacer, if it ran away it would look like v-tach, right?

 

[DrankTheKoolaid]

re

Does the monitor memory print out show the moment of rate change?

 

[Shishkabob]

Hard to tell without the printout.



However, I've had 2 patients show with V-tach with a pulse. First one complained of chest pain when V-tach started... he got a lidocaine bolus then a drip, titrated up to control the V-tach. He got an IAD at the hospital.

Second patient went in to Vtach, but was 'asymptomatic'. I didn't do anything for him but keep a close eye on him due to us nearly pulling in to the ER at that point.



Both, when I noticed VT, got combo-pads put on in case I had to shock. As is often stated, "stable" VT doesn't stay stable for long, get ready to do something.

 

[lightsandsirens5]

Does the monitor memory print out show the moment of rate change?

I'm on again starting at 1800 tomorrow. I will try to figure out how to do that. I know it does print from memory, I just have never done it.

 

[bstone]

Interesting article on the topic. Runaway pacemaker seems to be most often due to a low battery of the pacemaker.

http://europace.oxfordjournals.org/content/7/6/592.full

 

[EnviroMed]

So, what would you have done here?

75 yom was seen by family to "pass out" and fall backwards off of a bar stool, landing on his back. According to his wife, he began coughing uncontrollably for about 10 seconds before hand and was completely unresponsive for 30 seconds to a minute on the floor. Pt was not eating anything, at the time.

Upon our arrival, pt presents with: A: Patent. B: Regular, Non labored. C: Strong radial pulse @ 60/min. LOC: Responds to verbal. Pupils: PEARL @ approx 4mm. Skin: Warm, very pale on neck and face, dry. Extremities pink c cap refil <2 sec. No bleeding noted. HEENT: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Neck: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Back: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Chest: Repeatedly denies chest pain. Pt has a pacer/defib implanted on L upper chest. Heart: Three lead shows a ventricular paced rhythm @60 bpm. Pt does not believe internal defib went off. Abd: Denies any pain. Appears atraumatic. Nothing significant noted on exam. Pelvis: Intact. Denies pain. Able to ambulate s assist. Neuro: GCS=15. Pt is CAOx3/4 (does not remember what happened). States he feels "just fine."

Initial vitals:
B/P: 132/78
PR: 60
RR: 14
SPO2: 98% on RA
D-Stick: 130
Monitor shows ventricular pacer with good capture

Started a line, loaded him on the gurney, and began to take him out to the truck. Load him in the truck and go to take another set of vitals:
B/P: 148/90
PR: 130
RR: 14
SPO2: 99% on RA
(I rechecked the pulse twice and got 150 the second time and 146 the third time.) We have been in the truck all of 15 seconds at this point, so I haul the monitor out from behind the head of the gurney and take a look. V-Tach @ 150. Look at pt, look at monitor, look at pt, look at monitor.......Pt is fine. Recheck vitals and get the same readings as before. In fact, the pt is no longer pale, and his skin color looks great.

About 5 minutes into the transport he converts back into his paced rhythm @ 60, at which point his vitals go back to like the first set, and he becomes pale again. A minuted or so later on, he goes back into V-Tach and pinks up, BP comes up. Did that several times all the way in to the ER.

What on earth is going on??? As a medic student I am racking my brain for what is up, but keep drawing blanks.

run away pace maker seems most plausible, also some pacemakers combos have a feature called "Anti-tachycardia pacing" or overdrive pacing, this allows the device to treat the v-tach without cardioverting. But that would require his heart rate be significantly elevated to overcome the ventricle controlled rate. It is possible the pacer was set too low if he was showing signs of low cardiac output @ 60 bpm. most probably his intrinsic rate is higher and thats sort of a back up just in case rate the machine is programmed at. As said before run away pace maker seems most likely, and possibly wasn't V-tach to begin with. then again we aren't electrophysiologists so..

 

[Handsome Robb]

run away pace maker seems most plausible, also some pacemakers combos have a feature called "Anti-tachycardia pacing" or overdrive pacing, this allows the device to treat the v-tach without cardioverting. But that would require his heart rate be significantly elevated to overcome the ventricle controlled rate. It is possible the pacer was set too low if he was showing signs of low cardiac output @ 60 bpm. most probably his intrinsic rate is higher and thats sort of a back up just in case rate the machine is programmed at. As said before run away pace maker seems most likely, and possibly wasn't V-tach to begin with. then again we aren't electrophysiologists so..

So couldn't we disable the internal pacer/AICD with a magnet to confirm or rule out the theory of a runaway pacer. Now with that said once you remove the magnet have you permanently disabled the device or will it reset itself?

 

[TomB]

So couldn't we disable the internal pacer/AICD with a magnet to confirm or rule out the theory of a runaway pacer. Now with that said once you remove the magnet have you permanently disabled the device or will it reset itself?

This is device specific so ask to see the patient's ID card. I wrote a 3-part tutorial on the application of magnets to ICDs here:

http://ems12lead.com/2009/05/ineffective-or-inappropriate-icd-shocks-part-i/

In most cases tachy therapy is disabled while the magnet is applied and resumes when the magnet is removed but not with certain Boston Scientific devices.

Remember that patients with ICDs are susceptible to ventricular arrhythmias. It could be a pacemaker mediated tachycardia (in which case the application of a magnet will terminate the tachycardia) but it's more likely to be VT or even appropriate pacing. See this rhythm challenge for an example:

http://ems12lead.com/2010/11/rhythm-challenge-5/

Without seeing the rhythm strips and 12-lead ECG it's impossible to speculate on what was going on but ventricular pacing is part of the differential diagnosis for wide complex tachycardia when the patient has a device.

Usually a paced rhythm with the pacing lead in the apex of the right ventricle you will see LBBB morphology in lead V1 and a left axis deviation but patients with severe cardiomyopathy (like the ones who receive an ICD) don't always follow the rules.

Examine lead V4 very carefully for pacing artifact just prior to the QRS because that electrode is usually closest to the pacing lead itself.

 

[TomB]

A couple of other thoughts:

1.) Compare the morphology of the paced rhythm to the wide complex tachycardia. If the QRS complexes are essentially the same it's almost certainly a paced rhythm.

2.) This patient appears to be doing better with the tachycardia which lessens the likelihood that it's VT as opposed to pacing.

Upper-rate behaviors of pacemakers are complicated and features such as "paced Wenckebach" and rate smoothing are not uncommon to either prevent ventricular rates above the upper rate limit or prevent a sudden drop in heart rate (like this case).

For example, if it's an atrial tracking pacemaker and the upper rate limit is set for 150 and no advanced upper rate behaviors are programmed into the pacemaker there could be a sudden halving of the ventricular rate when the atrial rate exceeds 150 because the device would suddenly change from 1:1 pacing to 2:1 pacing.

The ventricular rate drops from 150 to 75 (for example) and the patient's cardiac output is suddenly cut in half which makes the patient symptomatic. So again, pacemaker behaviors are complicated and unless you know the indication for the device, the type of device and how it's programmed it's all speculation, although you can make an educated guess and if you observe a pacemaker's behavior long enough you can figure out how it's programmed.

This is device specific so ask to see the patient's ID card. I wrote a 3-part tutorial on the application of magnets to ICDs here:

http://ems12lead.com/2009/05/ineffective-or-inappropriate-icd-shocks-part-i/

In most cases tachy therapy is disabled while the magnet is applied and resumes when the magnet is removed but not with certain Boston Scientific devices.

Remember that patients with ICDs are susceptible to ventricular arrhythmias. It could be a pacemaker mediated tachycardia (in which case the application of a magnet will terminate the tachycardia) but it's more likely to be VT or even appropriate pacing. See this rhythm challenge for an example:

http://ems12lead.com/2010/11/rhythm-challenge-5/

Without seeing the rhythm strips and 12-lead ECG it's impossible to speculate on what was going on but ventricular pacing is part of the differential diagnosis for wide complex tachycardia when the patient has a device.

Usually a paced rhythm with the pacing lead in the apex of the right ventricle you will see LBBB morphology in lead V1 and a left axis deviation but patients with severe cardiomyopathy (like the ones who receive an ICD) don't always follow the rules.

Examine lead V4 very carefully for pacing artifact just prior to the QRS because that electrode is usually closest to the pacing lead itself.

 

[Simusid]

This is device specific so ask to see the patient's ID card. I wrote a 3-part tutorial on the application of magnets to ICDs here:

http://ems12lead.com/2009/05/ineffective-or-inappropriate-icd-shocks-part-i/

In most cases tachy therapy is disabled while the magnet is applied and resumes when the magnet is removed but not with certain Boston Scientific devices.

Remember that patients with ICDs are susceptible to ventricular arrhythmias. It could be a pacemaker mediated tachycardia (in which case the application of a magnet will terminate the tachycardia) but it's more likely to be VT or even appropriate pacing. See this rhythm challenge for an example:

http://ems12lead.com/2010/11/rhythm-challenge-5/

Without seeing the rhythm strips and 12-lead ECG it's impossible to speculate on what was going on but ventricular pacing is part of the differential diagnosis for wide complex tachycardia when the patient has a device.

Usually a paced rhythm with the pacing lead in the apex of the right ventricle you will see LBBB morphology in lead V1 and a left axis deviation but patients with severe cardiomyopathy (like the ones who receive an ICD) don't always follow the rules.

Examine lead V4 very carefully for pacing artifact just prior to the QRS because that electrode is usually closest to the pacing lead itself.

Tom, in your (excellent) article you say:

"If the ICD is effectively terminating episodes of VF or pulseless VT, that’s one thing. Clearly, the patient needs special treatment at the hospital and the antitachydysrhythmia functions of the device should not be disabled.

However, if the device is shocking a conscious, hemodynamically stable patient, and the rhythm is not changing after the ICD shocks, a ring magnet should be applied, and the antitachydysrhythmia functions of the device should be disabled."

It is coincidental that we had a call in just the past 2 days to a patient that was shocked a min of 7 times by his ICD. I believe (but I'm not positive) that the patient was conscious and stable, or at least alert. My question is, do you know of any systems that carry magnets to disable ICDs in a prehospital setting? I asked my general manager and he says it is not in our protocols.

Our patient was successfully treated with Cardizem.

 

[18G]

Tom, in your (excellent) article you say:

My question is, do you know of any systems that carry magnets to disable ICDs in a prehospital setting? I asked my general manager and he says it is not in our protocols.

Pennsylvania and Maryland allow ICD magnets pre-hospital.

 

[TomB]

South Carolina has a state protocol that allows application of a ring magnet with online medical control. Just because "it's not in the protocols" doesn't mean it shouldn't be!

 

[VFlutter]

run away pace maker seems most plausible, also some pacemakers combos have a feature called "Anti-tachycardia pacing" or overdrive pacing, this allows the device to treat the v-tach without cardioverting. But that would require his heart rate be significantly elevated to overcome the ventricle controlled rate. It is possible the pacer was set too low if he was showing signs of low cardiac output @ 60 bpm. most probably his intrinsic rate is higher and thats sort of a back up just in case rate the machine is programmed at. As said before run away pace maker seems most likely, and possibly wasn't V-tach to begin with. then again we aren't electrophysiologists so..

+1, Pacemakers can go into "Pacemaker Mediated Tachycardia" in which the pacemaker paces at the maximum rate programed. It can look just like V tach, its basically a reentry rhythm much like AVNRT. In a 3 lead you could have missed the pacer spikes. Also its not that uncommon for patients to be in Sust. V Tach and to be asymptomatic.

Another thing to note is the type of pacemaker they have. Some of the new ones like CRT-D's can do some crazy stuff.