SupravetricularTachyarrhythmias

Part 1

Rey Vivo, MDAssistant Professor of Medicine

Texas Tech University Health Sciences Center

Objectives

• Define the mechanisms of arrhythmias

• Understand the relevance of the site of origin to the arrhythmia

• Recognize and differentiate the Supraventricular Arrhythmias

“You see only what you look for, you recognize only what you know.”

Basics

• Two most important aspects of arrhythmias:1. Their mechanism2. Their site of origin

The two mechanisms that produce arrhythmias are:

1. Automaticity (problems of impulse formation)

2. Block or Reentry(problems of impulse

conduction)

SVTs

• Accelerated Automaticity

• Reentrant Atrial Tachyarrhythmias

• Reentrant Junctional Tachyarrhythmias- The Atrioventricular Nodal and Bypass Tachycardias

Accelerated Automaticity

1. Sinus Tachycardia

2. Atrial Tachyarrhythmiase.g. PAT with Block, MAT

3. Accelerated Junctional Rhythm

Reentrant Atrial Tachs

1. Atrial Flutter

2. Atrial Fibrillation

Accelerated Automaticity

Accelerated Automaticity

• May originate from any of the pacemaker cells

• “Ectopic” – any rhythm that comes from any other site than the SA node

Site Term Rate RangeSA node Sinus tachycardia 100-200 bpm

Atria Atrial tachycardia 100-200 bpm

Common bundle AJR 60-130

Bundle branches AVR 50-110

Sinus Tachycardia

Tips:1. Max. rate: 220 – age2. Discrete, antegrade P waves3. Short PR interval4. Normal QRS duration

Sinus Tachycardia

Atrial Tachycardias

1. Accelerated atrial rhythm

2. Paroxysmal Atrial Tachycardia with Block

3. Multifocal Atrial Tachycardia

Accelerated Atrial Rhythm

Accelerated Atrial Rhythm

PAT with Block

PAT with Block

Wandering Atrial Pacemaker-Multifocal Atrial Tachycardia Spectrum

MAT

Acelerated Junctional Rhythm

Acelerated Junctional Rhythm

Reentrant Atrial Tachyarrhythmias

Reentrant Atrial Tachs

• Atrial flutter • Atrial fibrillation

Single circuit,Uniform F waves

Multiple circuits,Multiform f waves

Atrial Flutter

Flutter waves best seen oninferior leads (II, III, aVF) and V1

Atrial Flutter

Atrial Flutter

Atrial Flutter

Atrial Fibrillation

Fibrillatory waves best seen ininferior waves and V1

Atrial Fibrillation

Atrial Fibrillation

Let’s practice!

We make most mistakes because of failure to apply reason and logic,

not because of ignorance.

Barney Marriott, MDEKG expert

Author, Practical Electrocardiography

EKG 1

EKG 2

EKG 3

EKG 4

EKG 5

EKG 6

EKG 7

EKG 8

EKG 9

The End(Part 2 next Tuesday)