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Matters of the Heart - V-Tach

What is Ventricular Tachycardia (V-Tach)?

Ventricular Tachycardia can be a life-threatening arrhythmia. Usually referred to as V-Tach or VT, this arrhythmia is easy to recognize on an EKG/ECG. It is defined as a heart rate faster than 100 bpm, with re-entry electrical impulses in the ventricles causing them to contract giving the EKG/ECG a slinky-like wide complex QRS.

V-Tach signals originate from the ventricles rather than the SA or AV node and creates a contraction that occurs before the SA node has a chance to send out a signal... AKA a Premature Ventricular Contraction (PVC). A PVC can be harmless but multiple PVCs in a row can cause issues. More than 3 PVCs in a row is labeled V-Tach. If the PVCs last longer than 30 seconds in a row it is termed Sustained Ventricular Tachycardia (NOT abbreviated SVT, FYI).

When the heart is pumping at an accelerated rate and not communicating with the atria, blood circulation is compromised (decreased) and contractions are ineffective. This can cause hypotension and decreased myocardial perfusion which can lead to Ventricular Fibrillation (V-Fib). The body can only sustain V-Fib for 6 minutes after which death occurs.

So it is safe to say that this is a scary rhythm that as a nurse, you need to know about.

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What does Ventricular Tachycardia (V-Tach) look like?

There are two different types of Ventricular Tachycardia.

  • Monomorphic

    • The waves are the same height

  • Polymorphic

    • The waves are different heights

    • Two types:

      • Long QT (>450ms) AKA Torsades de Pointes

      • Not long QT (<450ms)

(Source)

Note: The waves are the same height and width thus MONOmorphic.

(Source)

Note: The waves vary in height and width thus POLYmorphic.


In Ventricular Tachycardia, there aren’t any P waves… because the atria aren’t sending signals or contracting properly! The T waves are lost in the QRS so you can’t measure things like the QT interval. The rate is regular and faster than 100 beats per minute.

You also can differentiate between sustained VTach and non-sustained, which is self-explanatory.

Signs and symptoms of Ventricular Tachycardia (V-Tach)

The most common sign or symptom of V-Tach is palpitations, but can also be chest pain, dizziness, lightheadedness, dyspnea, nausea diaphoresis, and/or loss of consciousness. If a patient is not in sustained V-Tach, they may not have any signs or symptoms, making it hard to recognize this arrhythmia without an EKG/ECG. Then again if it is not sustained and is asymptomatic it probably won’t need any intervention anyway.

Nursing interventions/Considerations for Ventricular Tachycardia (V-Tach)

The very first thing you need to do, before you do ANYTHING else, is check for a pulse.

This is so important I am going to repeat it.

If your patient even sorta, kinda, maybe, possibly looks like they could be in V-Tach, CHECK A PULSE FIRST.

Note: If the patient does not have a pulse this is called pulseless v-tach or pVT.

Note on above note: This is concerning.

After checking for a pulse, make sure the patient is on a 3 or 5 lead cardiac monitor. If you do not have a 12-lead EKG/ECG, get one quickly.

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But do not leave your patient, so call for help and ask for an EKG/ECG machine.

If the patient is in V-Tach per the 12-lead EKG/ECG, call for help, grab the crash cart, and place the patient on the defibrillator. You will need multiple nurses in the room as well as at least one provider, preferably an attending doctor. You will then follow the ACLS algorithm.

Listen, It is one thing to be ACLS certified, it is quite another to actually perform Advanced Cardiac Life Support. So what I am saying to you is know your drugs, know your times, know the algorithm, and know HOW TO USE THE defibrillator. When a patient is in V-Tach is not the time to second guess or be like, “I think I know what I am doing.”

I am going to admit something here... My first time using ACLS in real life, I did not remember the proper dosages and I couldn’t remember if I was supposed to check a pulse or give epi or how many joules to shock with… Needless to say, it was scary, exhilarating and humbling. I cannot be more thankful that there were people in the room whom had more experience and guided me.

In these situations, it is natural for leaders to lead and others to help or take on one role (like being in charge of the defibrillator or being in charge of the meds for example). This is usually true for any particular situation that requires teamwork, actually, but especially in the healthcare setting.

The first time it happened to me, I was almost mad at myself for not remembering everything that I SHOULD know as an ACLS provider. That is why I highly recommend that you get comfortable with the ‘must know’ information of ACLS.

For example, if someone asked you to push Amiodarone in pulseless V-Tach, would you know how much to draw up and how fast to push it? Do you know when to push that drug fast and when to push it slow? And how slow is slow? My point is that you don’t want to be asking these questions when someone's life depends on it.

 

In a code, things will be slightly chaotic because tensions are as high as the stakes. You will feel slightly overwhelmed, especially if you are new to this scenario or if you don’t deal with ACLS very often. This is normal! Don’t be scared, be prepared with the basics and people will take on roles based on their experiences and strong suits. Good nurses and providers will set you up for success (and the patient for that matter)!

 

What causes Ventricular Tachycardia?

Be thinking about the common causes of cardiopulmonary arrest, since it could be a cause of V-Tach. Remember the H’s and T’s of Cardiopulmonary Arrest?

Your H’s

  • Hypoxia

  • Hypovolemia

  • Hydrogen ion (acidosis)

  • Hypothermia

  • Hypokalemia OR Hyperkalemia

Your T’s

  • Toxins- such as digitalis toxicity from digoxin, or antiarrhythmic toxicity from procainamide or quinidine for example.

    • This occurs because some medications increase reentry in phase 4 of the cardiac cycle.

  • Tamponade

  • Tension Pneumothorax

  • Thrombosis (Coronary and Pulmonary)

If you identify a potential cause, try to reverse it, within your nursing scope of practice, of course. For example, hypothermia? Get the ranger and warm the fluids going in or grab blankets, the bair hugger, heat packs, etc. Hypoxia? Throw some O’s on.

 

Other causes of Ventricular Tachycardia include:

  • Increased myocardial excitability

  • Coronary Artery Disease (CAD)

  • Electrolyte Imbalance- Like Potassium

  • Valvular disease

  • Rewarming Shock

Treatment: Meds/Tests/Imaging for Ventricular Tachycardia (V-Tach)

If the patient has a pulse, place them on the defibrillator to transcutaneously pace them.

Steps to transcutaneous pacing:

  1. Place defibrillator in pacemaker mode.

  2. Set pacemaker to demand

  3. Turn the RATE to 70 beats per minute OR their intrinsic rate

  4. Turn the miliampules (mA) to 70

  5. Increase the mA by 5-10 mA until the pacer captures

    1. Capture means that you can see on the monitor the pacer making the heartbeat at the rate you are asking it to beat at.

  6. Once you get to capture, place the mA to 5-10 mA above what the capture was.

    1. So if you have captured at 90 mA, then increase it to 95-100 mA.

If they do NOT have a pulse, follow the ACLS algorithm which is as follows:

The minute you find a patient unresponsive without a pulse call for help and GET ON THE CHEST.

I sing in my head “Staying Alive” by the Bee Gees and do compressions based on the beat for this song. Specifically, this part of the song is exactly 30 compressions:

“Whether your a brother or whether your a mother you’re staying alive, stayin’ alive
Feel the city shakin’ and everybody shakin’ and were stayin’ alive, stayin’ alive
Ah, ha, ha , ha stayin’ alive, stayin’ alive.
Ah, ha, ha, ha, stayin’ alive, stayin’ alive.”

Push hard and push fast, for two minutes. I remember this because I have two hands that push for two minutes. During the chest compressions, someone will need to bring the crash cart and attach the defibrillator.

After two minutes, it’s time for a rhythm and pulse check.

If it is a shockable rhythm, shock it. Re-assess pulses and rhythm. If pulses have returned, fist pump the air and prepare for Post-ROSC (Return of Spontaneous Circulation).

If pulses have not returned (and the rhythm is still whack), get back on that chest, bring out your mental disco ball and giddy-up for round 2 where we add Amiodarone to the party.

If it is not a shockable rhythm (and still no pulses) return to chest compressions.

 

When using a defibrillator:

Deliver the shock on the R wave (the top of the QRS). This is to avoid delivering a shock on the T wave… which can cause Ventricular Fibrillation. Which remember earlier when we talked about the T wave being lost in the QRS… well that is why it is important to deliver the shock at the top of the wave to avoid the hidden T wave.

Note: This picture above is NOT to scale and is NOT a real EKG. It was a drawing I made to replicate monomorphic V-Tach. I am aware of how amazing it looks and no I am not currently able to be commissioned for my mad drawing skills, but thank you for the compliment!

On the algorithm there is a side note about shock energy. I want to clear this up because I was SO confused by this. As a nurse in the hospital, you will be using a biphasic defibrillator that has the option of being used as an AED, which is monophasic.

If you are shocking with a monophasic defibrillator you shock at 360 Joules of energy. There isn’t a choice, that's just what it is. I remember this by thinking: circles are ‘mono’ (same/equal/symmetrical) and they go 360 degrees, thus Monophasic gets 360 J of energy. Most monophasic defibrillators are found in public and can be found on a basic EMT ambulance.

If you are shocking with a biphasic defibrillator (which is found in the hospital and on paramedic rigs) you will administer between 120 Joules to 200 Joules of energy for shock. The amount of Joules chosen is based on the manufacturer recommendation. If you don’t know what that recommendation is, then use the highest amount of Joules that machine will deliver (go big or go home).

While the CPR cycle is rotating, another nurse should be keeping track of the time that pulse checks happen as well as when epinephrine is administered.

Epinephrine is administered every 3-5 minutes. I remember this by the letter E.    

Get it? There are three points on the one side, plus the two points on the other equals 3-5. I honestly don’t know how I think of these things or why they work for me but my hope is that my weird quirky way of remembering things will help at least one person...

Depending on the patient situation, sometimes Vasopressin can be used instead of Epinephrine. Vasopressin causes the vasculature to contract more whereas epinephrine causes more of a response to the cardiac muscle tissue. If a patient were septic while in cardiac arrest or in asystole, it may be appropriate to use Vasopressin for the first or second dose in place of Epinephrine.

 

NOTE: I have been avoiding talking about the airway because in the hospital, the doctor and respiratory therapist (RT) will likely be taking care of this while CPR and meds are handled by the nurses. (Also, unless you have an advanced degree in nursing, you will not be placing an advanced airway) HOWEVER, we all know the ABCs and the importance of airway, so I will say that if, for whatever reason, the airway is not managed right away by RT and/or an MD, it is your duty/responsibility to manage it. This would include, within your scope of practice, placing an Oropharyngeal Airway (OPA) or Nasopharyngeal Airway (NPA) if needed as well as using a bag-valve mask to give 2 respirations after 30 compressions (one round).


 

Long term/Extended care and treatment for Ventricular Tachycardia

There are three options for long term care for VTach. Most are used in conjunction together.

  • Medications

  • Implantable Cardiac Defibrillator (ICD)

    • Can be used for patients who are at high risk of developing VTach

    • Most common way to treat VTach long term

    • Isn’t prophylactic but rather a safeguard that shocks the patient out of VTach if they go into VTach.

  • Ablation

    • In most cases, a catheter is placed into the vein up to the heart and cells that are causing PVCs to occur are burned (ablated)

    • Usually used if medications are not working and if the ICD continues to fire (the patient keeps going into V-Tach)

 

Disclaimer: This material should be used to supplement your understanding of the cardiovascular system. Any use of the information given in this post series is at your own risk and should be verified prior to making it a part of your nursing practice. There may be affiliate links associated with some products but we promise that we will never recommend anything that we don’t use ourselves.

Sources

Merck Manuals

Mayo Clinic

National Library of Medicine National Institute of Health

Osmosis.org

Life in the Fast Lane

National Institute of Health

 

This post was written by Susan DuPont, BSN, RN, CEN. Susan DuPont of BossRN is a full-time bedside emergency room nurse in a level one trauma center. In her spare time, she likes to fish, hunt, and travel.