NBME Shelf Review (Part 6) – Common Arrhythmias

“Unstable” Arrhythmias



* Arrhythmias that cause* Hypotension* Pulmonary Edema* Chest Pain* Altered Mental Status



Supraventricular Tachycardia (SVT)



* Stable* Vagal maneuver* Adenosine* Beta blocker or calcium channel blocker* Unstable* SYNCHRONIZED cardioversion



Monomorphic Ventricular Tachycardia (VT)



* Stable* Amiodarone* Procainamide* Lidocaine* Unstable* SYNCHRONIZED cardioversion* Pulseless* Defibrillation



Polymorphic Ventricular Tachycardia (aka Torsades de Pointes)



* Known complication of prolonged QTc* Side effect of multiple medications* Antipsychotics* Methadone* Ondansetron* Give Magnesium Sulfate



High yield EKG patterns



* Long QTc* Wolf Parkinson White (WPW)* Brugada Pattern



Atrial Fibrillation



* Stable* Patient presents immediately after onset (<24-48 hours)* Synchronized cardioversion* Rhythm control medications* Amiodarone* Procainamide* Flecanide* Patient does not present immediately (or unknown onset)* Rate control* Beta blockers* Metoprolol* Calcium channel blocker* Diltiazem* Anticoagulation (heparin)* Unstable* Synchronized cardioversion* Atrial fibrillation with extremely fast rate (200+) is common in WPW* Atrial fibrillation with slow rate is common with Digoxin toxicity



Bradycardia



* AV Blocks* 1st Degree* 2nd degree (type 1)* 2nd degree (type 2)* 3rd degree* If symptomatic and stable…* Atropine* If they become unstable… * Transcutaneous or transvenous pacing



Additional Reading



* Life in the Fast Lane EKG Library (LITFL)* Tachycardias (EM Clerkship)* Bradycardias (EM Clerkship)