Ventricular Rhythms Flashcards

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What are premature ventricular contractions (PVCs)?

PVC is a contraction coming from an ectopic focus in the ventricles. It is the premature early occurrence of a QRS complex. PVCs are wide and distorted in shape.

Which of these are terms to describe a PVC? (Select all that apply)

Wide (correct)

Early complex (correct)

Narrow

Bizarre (correct)

What are unifocal PVCs?

PVCs that arise from the same ectopic foci.

What are multifocal PVCs?

PVCs that arise from different ectopic foci. Signup and view all the answers

What does bigeminy refer to?

A PVC every other beat. Signup and view all the answers

What does trigeminy refer to?

A PVC every third beat. Signup and view all the answers

What is a couplet PVC?

Two consecutive PVCs. Signup and view all the answers

What is a triplet PVC?

Three consecutive PVCs. Signup and view all the answers

What does an ECG show for PVC?

HR varies; rhythm is irregular due to PVCs. Signup and view all the answers

What are some common causes of PVCs? (Select all that apply)

Caffeine Signup and view all the answers

What is the clinical significance of PVCs in a patient with heart disease?

They can decrease cardiac output and lead to angina and heart failure. Signup and view all the answers

What defines ventricular tachycardia (V-tach)?

A run of three or more PVCs. Signup and view all the answers

What is the priority intervention for a patient with V-tach?

Check LOC and vital signs! Signup and view all the answers

What is the preferred treatment for stable patients with monomorphic VT?

Amiodarone Signup and view all the answers

What is the treatment for polymorphic VT with a long QT?

Magnesium Signup and view all the answers

What is the treatment for VT without a pulse?

Defibrillate Signup and view all the answers

What is ventricular fibrillation (V-fib)?

A severe derangement of the heart rhythm with multiple ectopic foci firing in the ventricle. Signup and view all the answers

What is the priority treatment for V-fib?

Defibrillation Signup and view all the answers

What does asystole signify?

Total absence of ventricular electrical activity. Signup and view all the answers

What is Pulseless Electrical Activity (PEA)?

Organized electrical activity is seen on the ECG but there is no pulse. Signup and view all the answers

What is the treatment for PEA?

CPR and Epinephrine. Signup and view all the answers

What do H’s and T’s refer to?

Causes of cardiac arrest including hypovolemia, hypoxia, and tension pneumothorax. Signup and view all the answers

Study Notes

Premature Ventricular Contractions (PVCs)

PVCs originate from an ectopic focus in the ventricles, causing early QRS complex occurrence.
Descriptors for PVCs include early complex, wide, bizarre shape, and high amplitude.
Unifocal PVCs arise from a single ectopic focus, presenting similarly.
Multifocal PVCs stem from multiple ectopic foci, leading to different shapes.

Types and Patterns of PVCs

Bigeminy indicates a PVC occurring every other beat.
Trigeminy refers to a PVC every third beat.
A couplet consists of two consecutive PVCs.
A triplet consists of three consecutive PVCs, indicative of a short run of ventricular tachycardia (V-tach).

ECG Characteristics

The ECG shows irregular rhythm with varying heart rates due to PVCs.

Etiology of PVCs

Common stimulants include caffeine, nicotine, stress, and exercise; also linked to low potassium and magnesium, hypoxia, fever, and several heart conditions such as myocardial infarction (MI) and cardiomyopathy.

Clinical Significance of PVCs

PVCs generally have no significance in healthy hearts.
In patients with heart disease, PVCs can decrease cardiac output and contribute to angina or heart failure.
In coronary artery disease (CAD) and MI, PVCs indicate ventricular irritability; assessment of patient response is critical.

Ventricular Tachycardia (V-tach)

Defined by three or more consecutive PVCs, V-tach occurs when an ectopic focus becomes the heart's pacemaker.
Assessment of level of consciousness (LOC) and vital signs is essential.

Types of V-tach

Monomorphic VT features consistent shape and direction in QRS complexes.
Polymorphic VT is characterized by changing shapes and sizes of QRS complexes.

Torsades de Pointes

A type of polymorphic VT associated with prolonged QT intervals and low magnesium levels.

Etiology of V-tach

Causes include myocardial infarction, coronary artery disease, electrolyte imbalances, cardiomyopathy, and drug toxicity; can occur even in patients without apparent heart disease.

V-tach Management

Stable patients with monomorphic or polymorphic VT: treatment options include amiodarone or adenosine.
Polymorphic VT with long QT in stable patients: magnesium, phenytoin, and pacing are treatments; discontinue QT-prolonging medications.

Emergency Interventions

For pulsed but symptomatic VT: synchronized cardioversion is recommended.
For pulseless VT: immediate defibrillation, CPR, and administration of epinephrine and amiodarone are necessary.

Ventricular Fibrillation (V-fib)

V-fib is a critical disorder characterized by disorganized electrical activity in the ventricles, leading to ineffective contractions and no cardiac output; classified as a lethal rhythm.

Etiology of V-fib

Common causes include acute MI, heart failure, electrolyte imbalances, hypoxia, acidosis, electric shock, and drug toxicity.

V-fib Management

Priority treatment involves defibrillation, high-quality CPR, and medications like epinephrine and amiodarone.

Asystole

Characterized by total lack of ventricular electrical activity, patients are unresponsive, pulseless, and apneic; classified as lethal and requires rhythm assessment in multiple leads.
Management includes CPR and epinephrine.

Pulseless Electrical Activity (PEA)

Defined by organized electrical activity on ECG without a pulse; it's the most common post-defibrillation dysrhythmia, with a poor prognosis unless the cause is promptly identified.
Management involves CPR and epinephrine, along with assessment for underlying causes.

H's and T's

Key reversible causes of PEA include:
- Hypovolemia
- Hypoxia/hypoxemia
- Acidosis (hydrogen ion excess)
- Electrolyte imbalances (hypo/hyperkalemia)
- Hypothermia
- Cardiac tamponade
- Toxin exposure
- Tension pneumothorax
- Thrombosis (pulmonary or coronary)

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers key terms and definitions related to ventricular rhythms, specifically focusing on Premature Ventricular Contractions (PVCs). You'll learn about the characteristics, types, and implications of PVCs, enhancing your understanding of cardiac rhythms.