Treatment of Cardiac Arrhythmias 

1. General Principles 
 
– Identify and treat underlying causes: electrolyte disturbances, ischemia, hypoxia, drug toxicity, thyroid disease. 
– Assess hemodynamic stability: if unstable (shock, syncope, hypotension) — electrical intervention; if stable — pharmacological management. 
 
2. Acute (Emergency) Management 

A. Bradyarrhythmias 
 
– Sinus bradycardia / AV block: 
  • Atropine 0.5 mg IV every 3–5 min (max 3 mg) 
  • If ineffective → temporary pacing (transcutaneous/transvenous) 
  • Dopamine or epinephrine infusion as alternatives 
 
B. Tachyarrhythmias 

1. Supraventricular Tachycardia (SVT) 
 
– Stable: Vagal maneuvers → Adenosine 6 mg IV (then 12 mg if needed) → β-blocker or Ca-channel blocker 
– Unstable: Synchronized cardioversion 
 
2. Atrial Fibrillation / Flutter 
 
– Rate control: β-blocker, diltiazem/verapamil, or digoxin 
– Rhythm control: Amiodarone, flecainide, propafenone, sotalol, or electrical cardioversion 
– Anticoagulation per CHA₂DS₂-VASc score (warfarin or DOACs) 
 
3. Ventricular Tachycardia (VT) 
 
– Stable: Amiodarone 150 mg IV over 10 min (repeat as needed), or procainamide/lidocaine 
– Unstable (with pulse): Synchronized cardioversion 
– Pulseless VT/VF: Immediate defibrillation + CPR 
 
4. Torsades de Pointes 
 
– IV magnesium sulfate 2 g over 1–2 min 
– Correct K⁺, stop QT-prolonging drugs, consider pacing 
 
3. Long-Term (Chronic) Management 
 
– Sinus node dysfunction / AV block → Permanent pacemaker 
– Atrial fibrillation/flutter → Rate/rhythm control, anticoagulation, or ablation 
– Paroxysmal SVT → Catheter ablation 
– Ventricular tachycardia → ICD ± amiodarone or ablation 
– Inherited arrhythmias → β-blockers, ICD, genetic counseling 
– Heart failure with arrhythmias → CRT if indicated 
 
4. Vaughan Williams Classification 



5. Special Considerations 
 
– Amiodarone: very effective but long-term toxicity (thyroid, liver, lung) 
– Sotalol: avoid in renal failure or prolonged QT 
– Ablation: for drug-refractory symptomatic arrhythmias 
– ICD: life-saving in ventricular arrhythmias or high-risk structural heart disease