Matters of the Heart - PVCs

Matters of the Heart - PVCs

Matters of the Heart - Premature Ventricular Contractions (PVCs)

Are PVCs significant?

Premature Ventricular Contractions, also referred to as PVCs, can be fairly common occurrence in patients on telemetry monitoring or on a 12-lead EKG. PVCs are another one of those things that can be harmless at times, but can also be indicators of impending complications. Thus, learning about PVCs and their relevance in the care of your patients can help you in identifying potential problems early.

What is a premature ventricular contraction (PVC)?

Simply put, a PVC is an ectopic contraction, meaning that the impulse that initiates contraction comes from somewhere other than the primary pacemaker of the heart, the sinoatrial node (SA node, which is located in the wall of the right atrium. 

In the case of PVC the impulse originates in the ventricles and ventricular contraction occur before the next expected sinus beat.

What does a PVC look like?

PVCs can actually take a few different forms, but for now let’s review what basic and singular PVCs look like.

  ( Source )   Note:  This strip appears to be NSR and on the 7th beat, to the far right, we have a PVC. Notice how the QRS complex with the PVC seems wide and stretched out. The ectopic nature of PVCs not only causes early contraction of the ventricles, but also it causes those ventricular beats to be abnormal.

 (Source)

Note: This strip appears to be NSR and on the 7th beat, to the far right, we have a PVC. Notice how the QRS complex with the PVC seems wide and stretched out. The ectopic nature of PVCs not only causes early contraction of the ventricles, but also it causes those ventricular beats to be abnormal.

 

So, pictured above is a basic and singular PVC. Random and infrequent PVCs, like the one above, are usually harmless. So let’s talk about when PVCs aren’t so sweet and innocent…..

PVCs are like jelly beans. You know how there’s always that one flavor of Jelly Bean in a pack that tastes horrible, you know…. like the black licorice flavored beans….

As long as you only have the occasional nasty flavored jelly bean, everything is fine. However, if you have numerous nasty jelly beans, aka PVCs, then things just aren’t right. Lol!

To summarize, seeing an increase in the frequency and quantity of PVCs can mean that “something wicked this way comes”.

One of the first pairing of PVCs is called a call a couplet (pun kind of intended). This is when 2 PVC beats occur in a row, like in the image below.

  ( Source )   Note : Couplets may indicate increasing irritability of the cardiac tissue and that other problems may being coming in the future.

 (Source)

Note: Couplets may indicate increasing irritability of the cardiac tissue and that other problems may being coming in the future.

Remember, 3 or more PVC in a row is typically considered a burst of Ventricular Tachycardia (V-Tach) which can lead to Cardiac Arrest if left unaddressed.

Next the 2 forms of PVCs include Bigeminy and trigeminy. This is pretty self explanatory.

Bigeminy = Every second beat is a PVC.

  ( Source )   Note : Don’t let your brain confuse couplets and Bigeminy. Compare this rhythm image with the one of couplets. In Bigeminy the is a Normal beat and QRS complex between each PVC. Remember that couplets indicate that 2 PVCs are happening in a row.

 (Source)

Note: Don’t let your brain confuse couplets and Bigeminy. Compare this rhythm image with the one of couplets. In Bigeminy the is a Normal beat and QRS complex between each PVC. Remember that couplets indicate that 2 PVCs are happening in a row.


Trigeminy = Every third beat is a PVC.

  ( Source )

 (Source)

The final example of PVC subtypes we will review are Multiform PVCs. These are PVCs that occur, yet they are shaped differently on the ECG or 12 lead EKG, like below.

  ( Source )   Note : View how the 2nd and 4th QRS complexes are both wide and misshapen, yet they are completely different in appearance.

 (Source)

Note: View how the 2nd and 4th QRS complexes are both wide and misshapen, yet they are completely different in appearance.

 

Thus all of these forms of PVC can indicate increasing irritability of the cardiac muscle or conduction system.

Why do PVCs happen?

PVC are interesting. There are a lot of different things that can actually cause PVCs. Something as simple drinking a caffeinated soda or Alcohol can cause PVCs.

Other causes of PVC can be as follows:

  • Imbalance of Electrolytes.

  • Drug overdoses of substance such as cocaine, amphetamines, and antidepressant medications.

  • Pacemakers

  • Caffeine consumption

  • Alcohol Consumption

  • Cardiomyopathy

  • Heart Failure

  • Mitral Valve Issues

  • Displaced Pacemaker leads or Swan-Ganz Catheters

  • Nicotine consumption

  • Inflammation of the myocardial tissue

  • Decreased Oxygenation

  • History of having a Heart Attack or new heart attacks.

  • Chronically high blood pressures.

Clinical Manifestations of PVCs

It is possible for some people to have virtually no symptoms with PVCs.

EKG/ECG:

  • QRS Complex is widened and is typically greater than 0.12 in measurement.

  • You can measure the width of the QRS using actual calipers or digital calipers, if your facility has machinery capable of doing that. You can also use the R-Cat EKG Badge Tool I talk about in my “What’s on a badge?” post.

  • Underlying rhythm can be different depending on the patients diagnosis.

Physiological Signs and Symptoms

  • Feelings of having palpitations or a “skipped heart beat”.

  • Interruption to the normal lub-dub when auscultating the heart sounds.

  • Decrease in BP and syncope, especially when the PVC are frequent and regular.

Nursing interventions/Considerations

  • Assessment and Reassessment: The biggest thing you can do for a patient experiencing PVCs is to be vigilant in your assessment and reassessment.

  • Be a good health historian. Is this the first time the patient has had PVCs or skipped heart beats? How often are they occuring. Are they singular over are they couplets?

  • If the PVCs are new, occurring more frequently, or are changing in appearance and nature, report it to the provider (MD/DO, NP, PA) at your earliest and most reasonable opportunity.

  • Obtain an EKG per your facility standing order protocol or via provider order, especially if the PVCs are frequent and new.

  • Be sure to assess all vital signs regularly and in accordance with the policies at your institution.

  • Keep in mind that patients experiencing frequent PVCs will likely need to be on continuous telemetry monitoring and may require vital signs more frequently (at least every 2-4 hours) to establish how the patient is responding to the PVCs. If a provider doesn’t order this, inquire if they would like to start telemetry monitoring.

  • If the patient becomes symptomatic, but remains conscious,  alert the provider immediately and also collaborate with your charge nurse and other experienced clinicians. If the patient’s condition continues to worsen or the PVCs increase in frequency, it may be wise to activate your systems rapid response system, especially if the provider is quickly not available to assess the patient and provide orders.

  • Never be afraid to suggest escalation of care, if the patient’s condition appears to be worsening. When a patient's level of care needs to be escalated, this means that they may need to transfer to a unit that is better equipped to deal with more acutely or critically patient. The following are some examples of escalating care.

  • Med/Surg to Telemetry monitoring units, in hospitals that don't have global and remote telemetry monitoring.

  • Med-Surg/Telemetry Unit to Stepdown

  • Stepdown to ICU

  • As you see, escalating care doesn’t always mean sending a patient to the ICU. Sometimes it can mean sending them to another unit that may have resources to better manage the patient.

  • Try to obtain printed out copies of when PVCs are occurring or obtained an ECG.

  • If you are at a facility that allows events, such as PVCs and Vtach to be recorded and reviewed electronically, review these and assess any patterns.

  • When calling the doctor about PVCs, always have the following:

  • Patient Demographic info: Name, Room Number, Date of Birth, Medical Record Number

  • Brief and Concise reason for call, follow SBAR format.

  • Most recent set of VS

  • Most recent BMP or Chem 7 lab results

  • Have patient current medications and MAR pulled up to reference

  • Tell whether the patient is symptomatic or asymptomatic: Is the BP low, HR Low or High, Dizziness, Palpitations? 

Treatment

Like so many other cardiovascular issues, the point of treatment for PVCs is to identify the underlying cause.

Laboratory Tests:

  • Basic Metabolic Panel (BMP), also know as a Chemistry 7 (Chem 7).

  • Comprehensive Metabolic Panel (CMP), also known as a Chemistry 12 (Chem 12). This test includes more electrolytes and other studies.

  • Some providers may not order a whole panel, but just want to know the levels of specific electrolytes. In that case, the following may be ordered.

  • Magnesium level -

  • Potassium (K+) level

  • Complete Blood Count (CBC) - Assessing for contributing factors, such as hypoxia secondary to anemia.

Meds/Tests/Imaging:

  • 12 lead EKG

  • Telemetry monitoring

  • Chest X-ray (CXR)

  • 2-D Echocardiogram

  • Holter Event Monitor (often in outpatient setting)

  • Dialysis if the patient’s have chronic or severe acute renal failure.

Medications:

  • Amiodarone

  • Lidocaine

  • Magnesium Supplements or IV replacement - Depending on the severity of the deficiency.

  • Potassium Supplements or IV replacement - Depending on the severity of the deficiency.

  • IV Fluids

  • Kayexalate - For Symptoms that could stem from Elevated potassium levels. This will help patients expel excess potassium via their bowels……….

  • Lasix - Potassium wasting Diuretic, will rid the body of excess potassium via excretion  from the kidneys and urine.

  • Calcium Gluconate - Particularly for elevated magnesium levels.

Any extended care

  • Limit patient’s caffeine intake, if PVCs are becoming more volatile, frequent, or regular.

  • Advise patients on limiting alcohol intake when PVCs become a complication.

  • Advise patient to report if they are having palpitations or any other suddenly occurring cardiac symptoms such as shortness of breath (SoB) or chest pain, even if it is brief.

  • Encourage the patient to keep a symptom journal, particularly in chronic cases or with those who will be wearing an event monitor.

  • Have the patient record when (date and time) what the symptom was and when it happened and what they were doing before the symptom began (I.e. were they sleeping, excited, mowing the lawn).

  • Encourage the patient to keep the symptom journal with them and to bring it with them to their emergency room, urgent care, or primary care office visits.

  • Also have them record what they did afterwards and what the results were. Did the symptom stop, continue, or come and go? Did they rest and find relief after 5 or 10 minutes? Did they take a medication? Did they continue doing what they were doing previously?

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

The American Heart Association Website

Pocket Guide for ECGs, Made Easy 6th Edition

ECG interpretation made Incredibly Easy! Pocket Guide, 3rd Edition

Mayo Clinic Website

Matters of the Heart - V-Tach

Matters of the Heart - V-Tach

Matters of the Heart - A-fib/A-flutter

Matters of the Heart - A-fib/A-flutter