Lecture Notes: Ventricular Tachycardia (V-Tach)

Introduction

• Ventricular Tachycardia (V-Tach) is an abnormal heart rhythm originating from the ventricles.
• Occurs due to abnormal electrical signals causing rapid ventricular contractions.
• Issues arise as ventricles fail to pump blood efficiently, impacting cardiac output.

Rhythm Characteristics

• Duration: Can be short or sustained.
  • Short duration: Series of premature ventricular contractions (PVCs).
  • Sustained: Continuous rhythm.
• QRS Complex: Hallmark of V-Tach.
  • Wide and bizarre, greater than 0.12 seconds.
  • Fast ventricular rate: 100-250 beats per minute.
  • Regular rhythm but unable to assess T wave, P waves, atrial rate, or PR interval.

Presentations

• Monomorphic V-Tach: Consistent presentation throughout.
• Polymorphic V-Tach (e.g., Torsades de Pointes): Varied presentation.

Causes of V-Tach

• Abnormal electrolyte levels, particularly potassium (hypokalemia).
• Myocardial infarction (heart tissue damage).
• Medication toxicity (e.g., digoxin toxicity).
• Heart disease (e.g., heart failure, coronary artery disease).

Causes of Polymorphic V-Tach (Torsades de Pointes)

• Medications prolonging QT interval (e.g., amiodarone, sotalol, procainamide).
• Low levels of calcium, magnesium, or potassium.

Treatment Approaches

• Immediate Attention Required: Risk of progression to ventricular fibrillation (fatal).
• Emergency Protocols:
  • Activate emergency response.
  • Acquire crash cart and defibrillator.
  • Follow ACLS (Advanced Cardiovascular Life Support) protocols.

Stable Patient (With Pulse)

• Administer antiarrhythmic medications (e.g., amiodarone IV).
• Consider synchronized cardioversion if medication fails.

Unstable Patient (With Pulse)

• Symptoms due to decreased cardiac output (hypotension, mental changes, weak pulse, chest pain).
• Synchronized cardioversion followed by antiarrhythmic medication.

Patient With No Pulse

• Start CPR immediately.
• Perform defibrillation and administer epinephrine.
• Administer medications during CPR (e.g., amiodarone, lidocaine).
• Secure the airway.

Treatment for Polymorphic V-Tach (Torsades de Pointes)

• Administer magnesium sulfate.
• Cease medications prolonging QT interval.
• Treat as ventricular fibrillation if no pulse (CPR and defibrillation).

Long-Term Management

• Potential implant of ICD (Implantable Cardioverter Defibrillator) to prevent recurrence.

Additional Resources

• Access more ECG videos through linked resources provided in the YouTube description.