Cardiology IIArrhythmias

ObjectivesO Describe the normal conduction in

the heartO Describe pathophysiology of

bradycardiasO Describe pathophysiology of

tachycardiasO Describe treatment of the above

CaseO 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

BradycardiasO 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 BlocksO “Hiccups” on the conduction

highway past the AV nodeO 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

TachycardiasO 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

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 SummaryO EMT

O ABCsO Call for ALSO Rapid Transport

O AEMTO IVO Cardioversion of V-tach, V-fib

O ParamedicO Atropine, pacing for bradycardiasO Vagal Maneuvers, Adenosine for narrow complex

tachyarrhythmiasO Amio, cardioversion for wide complex

tachyarrhythmia