EKG

Write This DownSVT – supraventricular tachycardiaSR ST SB SA / PAC WAP AT AF AF / JR PJC AJR JT JB / PVC IR AIR AR A VT

VF TDP

Sinus Rhythm• Rate: 60–100.• Regularity: Regular.• P waves: Normal, Upright, Uniform, 1 P-wave:1 QRS.• PRI: 0.12–0.20, constant.• QRS: <0.12, narrow• Cause: Normal.• Adverse effects: None.• Treatment: None.

Normal Sinus Rhythm

Sinus Bradycardia

Sinus Tachycardia

Sinus Arrhythmia

Atrial Rhythms• Wandering Atrial Pacemaker• Premature Atrial Contraction• Atrial Tachycardia• Atrial Flutter• Atrial Fibrillation

Wandering Atrial Pacemaker• Rate: <100.• Regularity: Irregular.• P waves: Morphology of P wave changes from focus site.• PR: Varies, but usually less than .20.• QRS: <0.12, narrow

Wandering Atrial Pacemaker

Premature Atrial Contraction• Regularity: Depends on underlying rhythm; usually regular except for

PAC• Rate: Usually normal; depends on underlying rhythm• P Wave: P wave of early beat differs from sinus P Waves; can be

flattened or notched; may be lost in preceding T wave• PRI: .12–.20 seconds; can be greater than .20 seconds• QRS: Less than .12 seconds

PAC

Atrial Tachycardia• Regularity: Regular• Rate: 150–250 beats per minute• P Wave: Atrial P wave; differs from sinus P wave; can be lost in

preceding T wave• PRI: .12–.20 seconds• QRS: Less than .12 seconds

Atrial Tachycardia

Paroxysmal Atrial

Tachycardia

Atrial Flutter• Regularity:

• Atrial Rhythm regular• Ventricular rhythm usually regular

• Can be irregular if there is variable block• Controlled vs Uncontrolled (over 100 in uncontrolled)

• Rate: • Atrial rate 250–350 beats per minute; ventricular rate varies

• P Wave: • Characteristic saw tooth pattern (F waves)

• PRI:• Unable to determine

• QRS: • Less than .12 seconds

Atrial Flutter

Atrial Fibrillation• Regularity:

• Grossly irregular• Rate:

• Atrial greater than 350 beats per minute• Ventricular rate varies greatly

• Controlled vs Uncontrolled (same as for A flutter)• P Wave:

• No discernible P waves (DO NOT mistake S for P); atrial activity is referred to as fibrillatory waves (f waves)

• PRI: • Unable to measure

• QRS: • Less than .12 seconds

Junctional Rhythms• Premature Junctional Contraction (PJC)• Junctional Bradycardia• Junctional Rhythm (Junctional Escape)• Accelerated Junctional Rhythm• Junctional Tachycardia• Supraventricular Tachycardia

Premature Junctional Contraction (PJC)• Rate: Can occur at any rate.• Regularity: Regular but interrupted by premature beat.• P waves: Inverted or absent.• PR: 0.12 secs if P wave precedes QRS.• QRS: <0.12 secs

PJC

Junctional Bradycardia• Rate: <40.• Regularity: Regular.• P waves: Inverted or absent.• PR: <0.12 secs if P wave precedes QRS.• QRS: <0.12 secs

Junctional Bradycardia

Junctional Rhythm (Junctional Escape Rhythm)• Rate: 40–60.• Regularity: Regular.• P waves: Inverted or absent.• PR: <0.12 secs if P wave precedes QRS.• QRS: <0.12 secs.

Junctional Rhythm

Accelerated Junctional Rhythm• Rate: 60–100. • Regularity: Regular.• P waves: Inverted or absent.• PR: <0.12 secs if P wave precedes QRS.• QRS: <0.12 secs

Accelerated Junctional Rhythm

Junctional Tachycardia• Rate: >100.• Regularity: Regular.• P waves: Inverted or absent.• PR: <0.12 secs if P wave precedes QRS.• QRS: <0.12 secs.

Junctional Tachycardia

Supraventricular TachycardiaPhrase used to describe a rapid, regular supraventricular arrhythmia when more accurate identification is impossible because P waves aren’t visible and rate is common to other arrhythmias. SVTs with Overlapping Rate Ranges:Sinus Tachycardia 100-160 beats/minAtrial Tachycardia 150-250 beats/minAtrial Flutter 150-250 beats/minJunctional Tachycardia 100-180 beats/min

Ventricular Rhythms• Premature Ventricular Contraction (PVC)• Idioventricular Rhythm• Accelerated Idioventricular Rhythm• Agonal Rhythm• Ventricular Tachycardia• Torsades De Pointes• Ventricular Fibrillation• Asystole, P-Wave Asystole• Ventricular Pacemaker• Dual Chamber Pacemaker (AV Sequential)

Premature Ventricular Contraction• Rate: Can occur at any rate.• Regularity: Regular but interrupted by premature beat.• P waves: Usually not seen.• PR: Not applicable.• QRS: Wide and bizarre in shape; >0.12 secs wide.

Premature Ventricular Contractions

Unifocal PVC’s (Come from same source)

Multifocal PVC’s

PVC

Can have couplets as well in which case two PVC’s would be “stacked” together, or you can have a “run”.

PVC

Idioventricular Rhythm• Rate: 20–40.• Regularity: Regular.• P waves: None.• PR: Not applicable.• QRS: Wide and bizarre; >0.12 secs wide.

Idioventricular Rhythm

Accelerated Idioventricular Rhythm• Rate: 40–100.• Regularity: Usually regular, but can be a bit irregular.• P waves: Usually not seen.• PR: Not applicable.• QRS: Wide and bizarre; >0.12 secs.

AIR

Agonal Rhythm• Rate: <20.• Regularity: Irregular.• P waves: None.• PR: Not applicable.• QRS: Wide and bizarre; >0.12 secs wide

AR

Ventricular Tachycardia• Rate: >100.• Regularity: Usually regular but can be a bit irregular.• P waves: Usually none; dissociated if present.• PR: Variable if Ps present.• QRS: Wide and bizarre; >0,12 secs wide

VT

Torsades de Pointes• Rate: >200.• Regularity: Regular or irregular.• P waves: None.• PR: Not applicable.• QRS: Wide and bizarre; >0,12 secs wide

TDP

Ventricular Fibrillation• Rate: Cannot be counted.• Regularity: Not applicable.• P waves: None• PR: Not applicable.• QRS: None; wavy or spiked baseline

VF

Asystole• Rate: Zero.• Regularity: Not applicable.• P waves: None (unless it’s P wave asystole).• PR: Not applicable.• QRS: None.

A

P wave Asystole

Heart Blocks (AV Node Blocks)NAMES

• First Degree Heart Block• Second Degree Heart Block Type I• Mobitz I, Wenkebach

• Second Degree Heart Block Type II• Mobitz II

• Third Degree Heart Block

Heart BlocksWHAT THEY ARE

• Three Degrees of AV block:• First degree:

• There is a delay in transmission of sinus impulses to the ventricle. Prolonged PR interval.

• Second degree: AV selectively blocks impulses• Some sinus impulses get through to ventricles, some don’t. Dropped beats.

• Third degree: junction will escape or ventricles• None of the sinus impulses gets through to ventricles. Dropped beats, AV

dissociation.* ALWAYS an underlying SINUS RHYTHM, P waves are therefore Sinus P waves

First Degree• Rate: Can occur at any rate.• Regularity: Depends on underlying rhythm.• P waves: Upright, matching, one per QRS.• PR: Prolonged (>0.20).• QRS: <0.12.

First Degree

Wenkebach (Second Degree Type 1)• Regularity: Irregular; R-R interval changes

as PR interval gets longer; characteristic grouped beating• Rate: Usually slightly slower than normal• P Wave: Upright and uniform; some P waves not followed by QRS

complexes• PRI: Progressively lengthens until one P wave is not conducted• QRS: Less than .12 seconds• “Wencke Walks Away”

Wenkebach

Second Degree HB Type 2

Third Degree Heart Block (Complete HB)• Regularity: Regular• Rate: 40–60 beats per minute if focus is junctional 20–40 beats per minute if focus is ventricular• P Wave: Upright and uniform; more P waves than QRS complexes• PRI: No relationship between P waves and QRS complexes; P waves

occasionally superimposed on QRS complexes• QRS: Less than <.12 seconds if focus is Junctional; >.12 seconds or

more if focus is ventricular

Complete HB

12 LeadsLateral Leads – I, aVL, V5, V6

Inferior Leads – II, III, aVF

Anterior Leads – V3, V4

Septal Leads – V1, V2

ST segment and T waveST depression with T wave inversion = Ischemia

ST elevation with or without T wave changes = Myocardial Injury

ST segment shapes

ST Depression/Elevation Significance• Considered significant if the ST segment is at least 2 boxes below

baseline• Texts vary, some may say 1 box

• Changes must be seen in 2 contiguous leads

Pathological Q WavesQ Wave Significance• Q > 1/3 QRS, or • Q > 1 box wide & NOT in lead III ALONE

Summary

Examples

Electrical Reciprocity• Only two main areas of the heart that do this: • Inferior and lateral leads• Septal and posterior (Not going to see posterior on 12 lead)

leads. • ST Elevation in II, III, AVF will cause ST Depression in I, AVL

(Maybe V5,V6)• Septal lead changes are one view to reflect posterior involvement

in a 12 lead

Electrical Reciprocity

Good R-wave Progression

Poor R-wave Progression

Example

Inferolateral STEMI with reciprocal changes

Inferior STEMI with reciprocal changes

Lateral STEMI with reciprocal ST depression

Anteroseptal STEMI with lateral extension

QRS Axis• Main direction electrical impulse travels in the heart• Normal Axis (0 to 90, +++)• Physiological LAD (0 to -30, ++-)• Pathological LAD (-30 to -90, +--)• Right Axis Deviation (RAD) (90 to 180, - any +)• Extreme RAD (180 to -90, ---)

• Look at leads I, II, and III

Normal QRS deflections