Cardiology II Arrhythmias

Objectives O Describe the normal conduction in the heart O Describe pathophysiology of bradycardias O Describe pathophysiology of tachycardias O Describe treatment of the above

Case O A 55 year old male calls 911 because his “heart is racing.” He initially is alert, oriented, and has mild shortness of breath. On physical exam, he has a regular tachycardia at 180, and monitor shows a regular, narrow-complex tachycardia. He denies chest pain. Midway through transport, he becomes less responsive, and his blood pressure drops as he starts sweating profusely.

Normal Conduction

ECG waveform

Normal ECG

Sinus Arrhythmia

Bradycardias O Caused by damage to the conduction system resulting in a “broken road” or by drugs (beta blocker, calcium channel blockers) O If due to drugs, reversible. If not, many require a permanent pacemaker O Our goal is to temporarily support the heart rate until one of those two happen. O Atropine or External Pacing are options.

Sinus Bradycardia

First Degree AV Block

Second Degree (Type I)

Second Degree (Type II)

Third Degree Block

Junctional Rhythm

Accelerated Idioventricular

Ventricular Escape

Ventricular fibrillation

What is this?

Asystole

Branch Blocks O “Hiccups” on the conduction highway past the AV node O Can involve the right bundle, the left bundle, or divisions of the left bundle

Right Bundle Branch Block

Left Bundle Branch Block

Bifasicular Block RB/LA

Bifasicular Block – RB/LP

Trifasicular Block

Tachycardias O Any heart rate greater than 100. O The key is using the pattern to determine what is causing the tachycardia O The treatment is even more diverse, thus, knowing the pattern is critical to choosing the correct therapy. O The three main branches of tachycardia are atrial, nodal, and ventricular

Sinus Tachycardia

Atrial Fibrillation

Atrial Fib with Abberancy

Multifocal Atrial Tachycardia

Atrial Flutter

AV Nodal Reentrant Tachycardia

Wolfe Parkinson White

Lown-Ganong-Lavine

AV Reciprocating Tachycardia

Ventricular Tachycardia

Torsades de Pointe

Miscellaneous

LVH

RVH

Hyperkalemia

Digoxin Toxicity

Brugada Syndrome

Wellen’s Syndrome

Treatment Summary O EMT O ABCs O Call for ALS O Rapid Transport O AEMT O IV O Cardioversion of V-tach, V-fib O Paramedic O Atropine, pacing for bradycardias O Vagal Maneuvers, Adenosine for narrow complex tachyarrhythmias O Amio, cardioversion for wide complex tachyarrhythmia