Rhythm Recognition.Rhythm Recognition.

Sinus, Atrial, Junctional / Nodal, Sinus, Atrial, Junctional / Nodal, Ventricular, Blocks, others.Ventricular, Blocks, others.

Aims and Objectives.Aims and Objectives.

To be able to calculate heart rate from ECG.To be able to calculate heart rate from ECG. To understand features of normal sinus To understand features of normal sinus

rhythm.rhythm. To recognise rhythm abnormalities from a To recognise rhythm abnormalities from a

variety of causes.variety of causes. To understand rhythms which may need To understand rhythms which may need

immediate / emergency action. immediate / emergency action.

Calculating HR.Calculating HR.

1500 / small squares1500 / small squares 300 / large squares300 / large squares

Is it normal sinus rhythm?Is it normal sinus rhythm?

Rate 60 - 100bpm?Rate 60 - 100bpm? Regular p wave to Regular p wave to

each regular QRS?each regular QRS?

Normal P wave Normal P wave appearance?appearance?

Normal and constant Normal and constant PR interval?PR interval?

Sinus Node Rhythms.Sinus Node Rhythms.

Sinus Tachycardia and Sinus Sinus Tachycardia and Sinus Bradycardia.Bradycardia.

All features of normal All features of normal sinus rhythm - sinus rhythm - EXCEPT - EXCEPT -

Rate <60bpm Rate <60bpm (bradycardia).(bradycardia).

Rate >100bpm Rate >100bpm (tachycardia).(tachycardia).

Sinus Arrhythmia.Sinus Arrhythmia.

Rate 60-100bpm.Rate 60-100bpm. Varies with respiration Varies with respiration

(more common (more common younger).younger).

Retains all features of Retains all features of sinus rhythm - except sinus rhythm - except regularity of QRS regularity of QRS complex.complex.

Usually cyclical.Usually cyclical.

Sinus Arrest.Sinus Arrest.

Time period without Time period without sinus node activation.sinus node activation.

Clear pause in normal Clear pause in normal rhythm.rhythm.

Often terminated by Often terminated by escape beat.escape beat.

Rhythm before and after Rhythm before and after usually normal.usually normal.

SA Block.SA Block.

Blocks occur as a Blocks occur as a multiple of the p-p multiple of the p-p interval.interval.

Measure out.Measure out.

Non-conducted beat Non-conducted beat from normal from normal pacemaker.pacemaker.

Rhythm before and Rhythm before and after normal.after normal.

Atrial Rhythms.Atrial Rhythms.

Premature Atrial Ectopic Beat.Premature Atrial Ectopic Beat.

Premature firing of Premature firing of atrial cell (faster than atrial cell (faster than SA node).SA node).

Earlier complex.Earlier complex.

Compensatory or non-Compensatory or non-compensatory pause.compensatory pause.

Return to normal Return to normal rhythm.rhythm.

Premature Atrial Ectopic BeatPremature Atrial Ectopic Beat

Run of Premature Atrial Beats.Run of Premature Atrial Beats.

Can occur in isolation Can occur in isolation or short runs.or short runs.

Atrial bigeminy / Atrial bigeminy / trigeminy.trigeminy.

Longer runs should Longer runs should really be termed as really be termed as SVT.SVT.

Symptoms :- RarelySymptoms :- Rarely

Causes :- More often in older pts.Causes :- More often in older pts.

Lung DiseaseLung Disease

StimulantsStimulants

Treatment :- Anti-arrhythmia’sTreatment :- Anti-arrhythmia’s

Wandering Atrial Pacemaker.Wandering Atrial Pacemaker.

Irregularly irregular Irregularly irregular rhythm.rhythm.

Multiple atrial Multiple atrial pacemakers firing at pacemakers firing at own rate.own rate.

Different p wave Different p wave morphologies.morphologies.

Different p wave Different p wave distance from QRS.distance from QRS.

Different QRS rate.Different QRS rate.

Atrial Tachycardia.Atrial Tachycardia.

Ventricular rate Ventricular rate >100bpm.>100bpm.

Atrial rate 160-250bpm.Atrial rate 160-250bpm.

Varying levels of conduction Varying levels of conduction (1:1, 2:1, 3:1 etc).(1:1, 2:1, 3:1 etc).

P waves abnormal or not P waves abnormal or not easily seen.easily seen.

Sometimes seen as part of T Sometimes seen as part of T wave or QRS.wave or QRS.

Atrial Tachycardia.Atrial Tachycardia.

SymptomsSymptoms Palpitations, which can be skipping, Palpitations, which can be skipping,

fluttering or pounding in the chest.fluttering or pounding in the chest.

Chest pressure or pain.Chest pressure or pain. Shortness of breath & FatigueShortness of breath & Fatigue Fainting, also known as syncope, or near-Fainting, also known as syncope, or near-

syncope.syncope. Lightheadedness or dizziness Lightheadedness or dizziness

CausesCauses CardiomyopathyCardiomyopathy

Chronic obstructive pulmonary diseaseChronic obstructive pulmonary disease Ischaemic heart disease Ischaemic heart disease

Rheumatic heart disease Rheumatic heart disease

Sick sinus syndrome Sick sinus syndrome

Digoxin toxicityDigoxin toxicity

TreatmentTreatment

Depends on the type and severityDepends on the type and severity

Medications:- anti-arrhythmic drugsMedications:- anti-arrhythmic drugs

Radio-frequency catheter ablation (RFA)Radio-frequency catheter ablation (RFA)

Cryo-ablationCryo-ablation

Atrial Flutter.Atrial Flutter.

Atrial rate 250-Atrial rate 250-350bpm.350bpm.

Usually regular QRS Usually regular QRS (can be variable (can be variable conduction).conduction).

Most commonly 2:1 Most commonly 2:1 conduction (150bpm conduction (150bpm ventricular and ventricular and 300bpm atrial).300bpm atrial).

Classic 'saw tooth'.Classic 'saw tooth'.

Atrial Flutter.Atrial Flutter.

CausesCauses

MI & Ischaemic Heart disease.MI & Ischaemic Heart disease.

HypertensionHypertension

Cardiomyopathy (congestive heart failure)Cardiomyopathy (congestive heart failure)

Mitral valve diseaseMitral valve disease

SymptomsSymptoms

PalpitationsPalpitations

Syncope & SOBSyncope & SOB

AnginaAngina

anxietyanxiety

TreatmentTreatment

Digoxin & Sotalol (lowers Digoxin & Sotalol (lowers ventricular rate).ventricular rate).

DC CardioversionDC Cardioversion

RF AblationRF Ablation

Anti-coagulants:- strokeAnti-coagulants:- stroke

Atrial Fibrillation.Atrial Fibrillation.

Irregularly irregular Irregularly irregular QRS.QRS.

No p waves - atrial rate No p waves - atrial rate >350bpm.>350bpm.

Fast or slow AV Fast or slow AV conduction.conduction.

Irregular baseline.Irregular baseline.

Atrial Fibrillation.Atrial Fibrillation.

CausesCauses

Mitral Valve DiseaseMitral Valve Disease

ThyrotoxicosisThyrotoxicosis

CardiomyopathiesCardiomyopathies

SymptomsSymptoms

Often no symptomsOften no symptoms

Light-headedness & dizzinessLight-headedness & dizziness

PalpitationsPalpitations

Chest painChest pain

TreatmentTreatment

Digoxin & Sotalol (lowers Digoxin & Sotalol (lowers ventricular rate).ventricular rate).

DC CardioversionDC Cardioversion

AF supression pacemakersAF supression pacemakers

R-F Ablation - PVIR-F Ablation - PVI

Junction and AV nodal Junction and AV nodal Rhythms.Rhythms.

Junctional Premature Junctional Premature Contraction.Contraction.

Premature beat Premature beat originating from AV originating from AV node.node.

Maybe antegrade or Maybe antegrade or retrograde P wave.retrograde P wave.

Compensatory / non-Compensatory / non-compensatory pause compensatory pause before restoration of before restoration of sinus rhythm.sinus rhythm.

Junctional Escape Beat.Junctional Escape Beat.

Failing of normal Failing of normal pacemaker (SA node).pacemaker (SA node).

Pause in electrical Pause in electrical activity (Sinus arrest).activity (Sinus arrest).

Escape mechanism from Escape mechanism from further down in pathway.further down in pathway.

AV node (slower intrinsic AV node (slower intrinsic rate).rate).

Junctional Rhythm.Junctional Rhythm.

Rate 40-60bpm (AV node Rate 40-60bpm (AV node intrinsic rhythm).intrinsic rhythm).

Regular.Regular. P wave retrograde, P wave retrograde,

antegrade or none.antegrade or none.

No SA nodal activity.No SA nodal activity. Pacemaker AV node.Pacemaker AV node. Conduction normal Conduction normal

from this point.from this point.

Accelerated Junctional Rhythm.Accelerated Junctional Rhythm.

Rate 60-100bpm.Rate 60-100bpm. Otherwise maintains Otherwise maintains

all features of all features of junctional rhythm.junctional rhythm.

Junctional Tachycardia.Junctional Tachycardia.

Rate >100bpm.Rate >100bpm. Maintains all other Maintains all other

features of junctional features of junctional rhythm.rhythm.

AV nodal re-entrant tachycardia.AV nodal re-entrant tachycardia.

Re-entry circuit in the AV Re-entry circuit in the AV node - abnormal pathway to node - abnormal pathway to ventricle.ventricle.

Commonest type of SVT.Commonest type of SVT. Rate usually 150+bpm.Rate usually 150+bpm.

Ventricular Rhythms.Ventricular Rhythms.

Ventricular Premature Ventricular Premature Contraction.Contraction.

Premature firing of a Premature firing of a ventricular cell.ventricular cell.

Ventricles already Ventricles already depolarised before SA depolarised before SA node impulse conducted node impulse conducted through.through.

Wide, bizarre complex.Wide, bizarre complex. No p wave.No p wave. Often normal variant Often normal variant

but can be associated but can be associated with ischemia.with ischemia.

VE

Ventricular Ectopic BeatVentricular Ectopic Beat

Bigeminy Bigeminy

TrigeminyTrigeminy

Ventricular Escape Beat.Ventricular Escape Beat.

Pause in regular activity Pause in regular activity (e.g. Sinus arrest, slow (e.g. Sinus arrest, slow AF).AF).

Ventricular focus takes Ventricular focus takes over as an escape over as an escape mechanism.mechanism.

Wide, bizarre complex.Wide, bizarre complex. Usually followed by Usually followed by

restoration of restoration of underlying rhythm.underlying rhythm.

Idio-ventricular Rhythm / Idio-ventricular Rhythm / Ventricular Escape Rhythm.Ventricular Escape Rhythm.

Rate 20-40bpm (intrinsic Rate 20-40bpm (intrinsic ventricular rate).ventricular rate).

Regular rhythm.Regular rhythm. No p wave.No p wave.

Wide abnormal QRS.Wide abnormal QRS. Usually connected to Usually connected to

3rd degree HB.3rd degree HB.

Accelerated Idio-ventricular Accelerated Idio-ventricular Rhythm.Rhythm.

Rate 40-100bpm.Rate 40-100bpm. Exactly same features Exactly same features

as ventricular rhythm.as ventricular rhythm.

Ventricular Tachycardia.Ventricular Tachycardia.

Rate 100-200bpm.Rate 100-200bpm. Regular.Regular. Occasional dissociated p Occasional dissociated p

waves.waves. Wide, bizarre QRS.Wide, bizarre QRS.

LBBB in V1 indicates RVOT LBBB in V1 indicates RVOT origin (pulse).origin (pulse).

RVOT also associated with RVOT also associated with VF (Brugada).VF (Brugada).

RBBB in V1 indicates LV RBBB in V1 indicates LV origin (usually no pulse).origin (usually no pulse).

Other Features to distinguish VT.Other Features to distinguish VT.

Capture beats - normal Capture beats - normal looking beat.looking beat.

Occurs at exactly right Occurs at exactly right time to be conducted time to be conducted through.through.

VT continues VT continues immediately following.immediately following.

Fusion beats - Fusion beats - combination of sinus combination of sinus and ventricular beat. and ventricular beat.

Torsade de Pointes.Torsade de Pointes.

Twisting of the axis.Twisting of the axis. Rate 200-250bpm.Rate 200-250bpm. Regular or irregular.Regular or irregular. Sinusoidal pattern.Sinusoidal pattern.

May revert to VF or May revert to VF or back to SR.back to SR.

Associated with Associated with electrolyte electrolyte abnormalities.abnormalities.

Ventricular Fibrillation.Ventricular Fibrillation.

Chaotic ventricular Chaotic ventricular activity.activity.

Rapid contraction - Rapid contraction - unable to produce unable to produce cardiac output.cardiac output.

If patient is fine and If patient is fine and awake - it is not.awake - it is not.

Check leads or get Check leads or get defibs.defibs.

Heart Blocks.Heart Blocks.

First Degree Heart Block.First Degree Heart Block.

Rate depends on Rate depends on underlying rhythm.underlying rhythm.

Regular.Regular. Prolonged PR interval Prolonged PR interval

>0.2secs.>0.2secs.

Physiologic block in the Physiologic block in the AV node.AV node.

Caused by Medication, Caused by Medication, vagal stimulation, vagal stimulation, disease.disease.

Mobitz I Second Degree HB.Mobitz I Second Degree HB.(Wenckebach).(Wenckebach).

Rate depends on Rate depends on underlying rhythm.underlying rhythm.

Regularly irregular.Regularly irregular. Increasing PR interval.Increasing PR interval.

Dropped beat.Dropped beat. Cycle starts over.Cycle starts over. Diseased AV node with Diseased AV node with

long refractory period.long refractory period.

Mobitz II Second Degree HB.Mobitz II Second Degree HB.

Rate depends on Rate depends on underlying rhythm.underlying rhythm.

Same PR interval for all Same PR interval for all conducted beats.conducted beats.

P waves usually regular.P waves usually regular.

Some p waves not Some p waves not conducted.conducted.

Can be 2:1, 3:1, 4:1 etc.Can be 2:1, 3:1, 4:1 etc. Usually progresses to CHB.Usually progresses to CHB.

Complete Heart Block (3rd Complete Heart Block (3rd Degree HB).Degree HB).

Atrio-ventricular Atrio-ventricular dissociation.dissociation.

Regular p waves.Regular p waves. Regular QRS.Regular QRS. No relationship.No relationship.

Rate depends on Rate depends on intrinsic rhythm (e.g. intrinsic rhythm (e.g. escape rhythm).escape rhythm).

Needs pacemaker.Needs pacemaker.

Other rhythms.Other rhythms.

Asystole.Asystole.

No cardiac activity.No cardiac activity. Check leads.Check leads. Resuscitation.Resuscitation. Chest compressions may Chest compressions may

cause ECG waveforms.cause ECG waveforms.

Important to stop to assess Important to stop to assess rhythm.rhythm.

Usually poor prognosis.Usually poor prognosis. Check for p waves - may Check for p waves - may

respond to pacing.respond to pacing.

Paced Rhythm.Paced Rhythm.

Pacing spike.Pacing spike. Single / dual chamber.Single / dual chamber. Bi-ventricular.Bi-ventricular.

Implantable Implantable defibrillator.defibrillator.