Arrhythmia Identification and Differentiation

Umarani1, Vijayalakshmi2

1Assistance Nursing Superintendent, Kauvery Heartcity, Trichy, India

2Non Critical Ward Nursing Incharge, Kauvery Heartcity, Trichy, India

Introduction to Arrhythmias:

Definition: Irregular heart rhythms, either in rate (fast or slow) or rhythm (irregular beats).

Causes: Most common – Heart disease, Electrolyte imbalances and medications, and Structural heart abnormalities.

Symptoms: Palpitations, dizziness, chest pain, shortness of breath, fainting.

Classification of Arrhythmias

Tachyarrhythmia

  • Supraventricular Tachycardia
  • Sinus tachycardia
  • AV nodal reentrant tachycardia
  • Atrial tachycardia
  • Atrial flutter
  • Atrial fibrillation

Ventricular Tachycardia

  • Monomorphic ventricular tachycardia
  • Ventricular Fibrillation
  • Torsade’s des pointes

Brady arrhythmia

Sinus node dysfunction

  • Sinus bradycardia
  • Sinus arrest
  • Tachy – Brady syndrome
  • Chronotropic incompetence

AV blocks

  • First – degree AV block
  • Second – degree AV block
  • Third – degree AV block

Atrial Fibrillation (AF)

  • Atrial Fibrillation is an irregular heart rhythm that begins in the upper chambers of the heart.

Clinical Significance:

  • Irregular heartbeat.
  • Chest pain
  • Fatigue
  • Dizziness
  • Shortness of breath
  • Heart palpitation

Causes

  • Obesity
  • Type II Diabetes
  • Chronic Kidney Disease
  • Heart Failure
  • Coronary Artery Disease
  • Congenital Heart Disease
  • Hyperthyroidism

Treatments

  • Cardioversion
  • Catheter ablation

Medicines

  • Beta blockers
  • Antiarrhythmics
  • Anticoagulants

Atrial Flutter

Atrial Flutter is a heart rhythm disorder that causes the upper chambers of the heart to beat too fast.

ECG Characteristics

  • Regular rhythm.
  • Saw tooth pattern (flutter waves) at ~300 bpm.

Symptoms

  • Palpitation
  • Shortness of breath
  • Fatigue
  • Chest pain

Treatment: Administer an antiarrhythmic, Cardioversion therapy.

Ventricular Tachycardia (VT)

Ventricular Tachycardia is a type of abnormal heart rhythm or arrhythmia.  Heart beats too fast in the lower heart chambers

ECG Characteristics

  • Wide QRS complexes, usually >120 ms.
  • Rate 120-250 bpm.
  • No P waves; dissociation from QRS complex.

Symptoms: Dizziness,Palpitation, Shortness of breath

Treatment: Cardioversion, antiarrhythmic drugs.

Differentiation: Monomorphic Vs Polymorphic VT

Ventricular Fibrillation (VF)

Ventricular Fibrillation is a type of irregular heart rhythm.  During ventricular fibrillation, the there is no effective cardiac contraction. Cardiac output fails

ECG Characteristics

  • Chaotic and irregular rhythm.
  • No identifiable QRS, P, or T waves.
  • Rapid, erratic electrical impulses.

Clinical Significance: Life-threatening, requires immediate defibrillation.

Differentiation: Compare to Pulseless Electrical Activity (PEA) or asystole (lack of electrical activity).

Supraventricular Tachycardia (SVT)

A very fast heart beat that may last for a few minutes to a few days

ECG Characteristics

  • Narrow QRS Complex.
  • Rate 150-250 bpm.

Clinical Significance

Common cause of palpitations, chest pain, dizziness

Treatment: Medication – Beta blocking agents and calcium channel agents, cardioversion and catheter ablation

Heart Block Overview

Types

  • First-Degree AV Block
  • Second-Degree AV Block (Type I and II)
  • Third-Degree (Complete) AV Block

ECG Patterns: Vary from PR interval changes to complete dissociation between atria and ventricles.

First-Degree AV Block

ECG Characteristics

  • Prolonged PR interval (>200 ms).
  • Normal sinus rhythm but delayed conduction.

Clinical Significance: Usually benign but can progress to higher-degree block.

Differentiation: Compare with Second-Degree AV Block.

Second-Degree AV Block-Type I (Wenckebach)

ECG Characteristics

  • Progressively lengthening PR interval until a QRS is dropped.
  • Regular pattern with occasional dropped beats.

Clinical Significance: Often benign, but monitoring is required.

Differentiation: Compare with Type II (Mobitz).

Second-Degree AV Block – Type II (Mobitz)

ECG Characteristics

Consistent PR interval, followed by dropped beats. More dangerous than Type I, can progress to complete block.

Clinical Significance: May require pacemaker if symptomatic.

Differentiation: Compare with Type I (Wenckebach), which has progressive PR interval lengthening.

Third-Degree (Complete) AV Block

ECG Characteristics

  • Complete dissociation between P waves and QRS complexes.
  • No relationship between atrial and ventricular rhythms.

Clinical Significance: Life-threatening; requires pacemaker implantation.

Differentiation: Compare with second-degree blocks, where some conduction occurs.

Clinical Considerations and Treatment

  • Management of Atrial Fibrillation: Rate control, anticoagulation, rhythm control.
  • Management of Ventricular Tachycardia: Antiarrhythmic drugs, cardioversion, defibrillation.
  • Heart Block: Pacemaker for advanced blocks.
  • Emergency Care: Life-threatening arrhythmias require immediate action (defibrillation, medications).

Conclusion: Early identification of arrhythmias is crucial for appropriate treatment. ECG interpretation is vital for distinguishing between different arrhythmias. Effective management can prevent complications such as stroke, sudden death, and heart failure.

Kauvery Hospital