ARRHYTHMIA

Objectives At the end of this session students should be able to:  Distinguish the normal from abnormal rhythms.  Understand the pathophysiologic basis of arrhythmia.  Differentiate ventricular from supraventricular arrhythmias.  Recognize different types of supraventricular arrhythmias.  Recognize the different types of heart block.  Be familiar with strategies of arrhythmia management.

Conduction system hierarchy

Basic ECG elements ST interval TP segment T wave QT interval ST segment QRS PR interval PR segment P wave Duratio n Intervals Joining Segments Basic elements

2 dimensions P Q R S T Time Axis

Electrical axis

Classification of arrhythmia

Mechanisms of arrhythmia Enhanced automaticity Triggered activity Reentry

Mechanisms of arrhythmia IMPULSE GENERATION IMPULSE CONDUCTION IMPAIRED CONDUCTION ENHANCED CONDUCTION IMPAIRED GENERATION ENHANCED GENERATION BRADYARRHYTHMIA TACHYARRHYTHMIA A. tachy Junct. Tachy Acc. J rhythm Acc. LV rhythm V. tachycardia Sinus pause Sick sinus syndrome High vagal tone Medication A. Fibrillation A. flutter PSVT VF & VT Pre-excitation SN exit block AV block Bundle branch & fascicular block

Reentry macro & micro reentry functional or structural

Rhythm analysis (P-QRS) Rhythm (P waves & QRS)Present Sinus / non sinus Absent Real / technical Rate (P waves & QRS)SlowAppropriate/inappropriate Fast Narrow/wide complex Regularity (P waves & QRS)Regular Irregular Group beating or haphazard P wave morphology & QRS morphologyAxis up/down P waves, extreme axis Duration & Axis Normal or wide (RBBB, LBBB), sup. axis P-QRS relationshipNormal 1:1, normal PR interval Abnormal Ratio, duration (fixed, variable, unrelated) Others PR & QT intervalsNormal Abnormal Long or short

Rhythm interpretation Pulse initiation P wave Present Deflection (Lead II & aVF) RateRegularity Consistency (Shape & rate) YNupdownFastNSlowReg.Irreg.YN QRS Present Morphology (duration) RateRegularityAxis YNNarrowWideFastNSlowReg.Irreg.NAbn Pulse propagation P-QRS Relation 1:1 <0.21:1 > 0.2Progressive 2:1Fixed 2:1Dissociation Conclusions: …………………………………………………………………………(diagnosis)

Normal sinus rhythm

Normal Sinus Rhythm

Sinus Tachycardia (Appropriate vs inappropriate)

Sinus Tachycardia

Sinus Bradycardia (Appropriate vs inappropriate)

Sinus Bradycardia

Sinus Arrhythmia (normal or abnormal?)

Sinus Arrhythmia

What is the abnormality ?

Premature atrial contractions (ectopic beats)

Premature Atrial Complexes

Atrial Tachycardia

Atrial Flutter

Atrial Fibrillation

Junctional Rhythm

Accelerated JR

Accelerated Junctional Rhythm

Junctional Tachycardia

Paroxysmal supra- ventricular tachycardia (AV nodal reentrant tachycardia)

Paroxysmal supra- ventricular tachycardia (AV nodal reentrant tachycardia)

Paroxismal SVT (AVNRT)

Clinical Signs of Tachyarrhythmia

1 st degree AV block

Type I second degree AV block

2 nd Degree Block Type 1

Type II second degree AV block

Second degree AV block (type- II)

Complete Heart Block (third degree AV block)

Complete heart block

Premature ventricular beats (RVOT type)

Isolated PVCS, couplets and tripplets

PVC with R on T phenomenon

What do you notice?

Non-sustained VT

Ventriculat tachycardia Why? PPPP

Monomorphic VT What is the mechanism?

Polymorphic VT What is the mechanism?

Ventricular fibrillation

What is this rhythm? Accelerated Idioventricular Rhythm

Idioventricular rhythm

Asystole

Case Study 5

QT (corrected) QTc= QT (msec) √R-R (sec) = 640/ 1.05 = 610 msec > 450 m sec is long Long QT syndrome (Jervell-Nielson-Lange)

WPW

Arrhythmia management Aim: Hemodynamic stability Prevent complications Symptomatic relief Strategies: Restoration of normal rhythm Slowing of tachyarrhythmia Augmenting the slow rhythm Options: Pharmacological agents Electrical cardioversion Transcatheter ablation Device implantation Emergency versus elective management Electrophysiology lab

Emergency cardioversion

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