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 RegularIrregular Irregularly Irregular: Afib Multifocal Atach Regularly Irregular: Aflutter with variable response Atach with var response P before QRS: Sinus tachy Atach Aflutter with 1:1 AV No p wave: SVT Atach ?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