Tachyarrhythmia

Gaurav Panchal

Arrhythmogenesis

• Impulse formation – Automaticity – inappropriate Tachy / brady;

accelerated Ventricular rate after MI. – Triggered activity i.e. Long QT, CPVT

• Impulse conduction – Block –

• Without re entry – SA/AV/ BBB• With re entry – WPW, AVNRT,

– Reflection • Both

– Interaction between automatic foci– Interaction between automaticity and conduction

Presentations

• Mode of presentation – Clinic vs Emergency

• Palpitations – Mode of onset – rest vs exercise – Mode of termination – Severity of symptoms

• Syncope • Dizziness / presyncope • SOB

Evaluate

• Drug history

• F/H

• Assess – HR, BP, ECG

• Effect of respiration, CSM

Case 1

• 24 year old female with palpitations – – fast, regular, – usually at rest, – subsides after holding breath or pouring cold

water on face, – usually lasts 25 min to 1 hour. – No presyncope / syncope / SOB

• QRS– >120ms = Broad Complex Tachycardia– <120ms = Narrow Complex Tachycardia

• P-QRS relation• Abnormal pattern of beats

– QRS morphology – normal / abnormal– P wave morphology – normal / abnormal

• Origin or termination of arrhythmia – P / QRS

SVT

• 90% reentrant, 10 % not reentrant

• 60% AV nodal reentrant tachycardia (AVNRT)

• 30% orthodromic reciprocating tachycardia (ORT)

• 10% Atrial tachycardia

• 2 to 5% involve WPW syndrome

Differential Dx of Regular SVT

• Short RP tachycardia– AV nodal reentrant tachycardia– AVRT– atrial tachycardia when associated with slow

AV nodal conduction

AVNRT

• Responds to vagal maneuvers in 1/3 cases

• Very responsive to AV nodal blocking agents such as beta blockers, CA channel blockers, adenosine.

• Recurrences are the norm on medical therapy

• Catheter ablation 95% successful with 1% major complication rate

• 2 pathways within or limited to perinodal tissue– anterograde conduction

down fast pathway blocks with conduction down slow pathway, with retrograde conduction up fast pathway.

• May have very short RP interval with retrograde P wave visible as an R’ in lead V1 or psuedo-S wave in inferior leads in 1/3 of cases . No p wave seen in 2/3

Management

• Vagal manoeuvres

• Pharmacological – Acute management – adenosine, flecainide,

amiodarone – Prevention – flecainide, propranolol, sotalol,

amiodarone

• RFA

Case 2

• 64 year old male with palpitations – acute onset for 12 hours – fast, regular, associated with dizziness on standing up. No syncope or SOB.

Management

• Cardioversion – Pharmacological – DCCV

• Ablation

• Rate control – Beta blockers– Amiodarone

• Anticoagulation

Narrow Complex Tachycardia

Regular Irregular

Irregularly Irregular:•Afib•Multifocal Atach

Regularly Irregular:•Aflutter with variable response•Atach with var response

P before QRS:Sinus tachyAtachAflutter with 1:1 AV

No p wave:SVTAtach?very fast AFIB

P>QRS:Aflutter

68 year old male collapse while on coffee table.

Management

• Acute stabilisation– Hemodynamically unstable – Hemodynamically stable – amiodarone,

lidocaine– Correct predisposing factors

• K+, hypotension, ischemia,

• Long term care – Anti-arrhythmic – beta blocker, amiodarone – ICD

• Cardiomyopathies– Ischaemic – DCM– HCM– ARVC

• TOF • Inherited arrhythmias

– CPVT– Brugada– Long QT – Short QT

• Idiopathic – Outflow tract – Annular – Fascicular

• Questions