Arrhythmias

Question 1

Treatment for tachycardia causing a patient to be unstable

Answer 1

DC Cardioversion

Question 2

QRS complex width determined by

Answer 2

His-Purkinje

Ventricles contracting

Question 3

Narrow complex tachycardia

Answer 3

Ventricles activated via normal conduction system (His-Purkinje)
In terms of mechanism, is supra ventricular tachycardia

Question 4

Supra ventricular tachycardias categories

Answer 4

Atrial flutter/tachycardia
Atrio-Ventricular Nodal Reentrant Tachycardia
Atrio-Ventricular Re-entrant Tachycardia

Question 5

Atrial flutter/tachycardia

Answer 5

Regular narrow complex

Originates from atria- focal or re-entrant circuit

Question 6

Atrial flutter

Answer 6

P wave- saw tooth like, most prominent in inferior (negative in inferior)
Counter-clockwise circuit in RA

Question 7

Atrial Fibrillation

Answer 7

Common
Prevalence increases with age
Fibrillatory waves
R-R waves irregular

Question 8

AF treatment

Answer 8

Acute rate + rhythm management- try to achieve haemodynamic stability
Manage Precipitating factors
Assess stroke risk
In long run, consider if continue with rate management or try to get them out of AF

Question 9

AF Stroke risk

Answer 9

Increased
CHADS VASc score
Oral anticoagulation

Question 10

AF rate + rhythm management

Answer 10

Catheter ablation

Question 11

Atrio-ventricular nodal re-entrant tachycardia

Answer 11

Small circuit that occurs around AV Nodal tissue
Reentry within AV node
Fast regular
Regular narrow complex tachy

Question 12

Atrio-ventricular re-entrant tachycardia

Answer 12

Typically occurs in patients with pre-excitation (initial slurring of QRS complex with short PR interval)

Question 13

Wolff-Parkinson-White syndrome

Answer 13

Arises from atrio-ventricular re-entrant tachycardia

Pre-excited ECG AND documented tachycardia/palpitation symptoms

Question 14

Orthodromic AVRT

Answer 14

Ventricle activated down His Purkinje system, activation going back up atrium via accessory pathway
Narrow QRS

Question 15

Antidromic AVRT

Answer 15

Ventricles activated by accessory pathway
Right ventricle activated before left- goes back up to atrium via AV node
Broad complex tachycardia

Question 16

Pre-excited AF

Answer 16

Fast broad irregular rhythm
AF in top chambers, AF goes down to ventricle via both AV node and accessory pathway
Accessory pathway conducts very fast so can have very fast rhythm- can lead to VF
Medical emergency
DC Cardioversion
Inpatient Ablation for accessory pathway

Question 17

Nodal dependent tachycardia

Answer 17

Termination with vagal manouver/adenosine

Question 18

Adenosine in atrial arrhythmias

Answer 18

Increase AV block

Doesn’t terminate tachy

Question 19

Narrow QRS- irregular

Answer 19

Possible AF

Treat AF

Question 20

Narrow QRS- Regular

Answer 20

Supra-ventricular tachy
Vagal manoeuvre to determine if nodal dependent
Adenosine- 6mg rapid bolus, if no effect further 12mg, if no effect further 12mg after –> if terminates, probably nodal dependent SVT
If sinus rhythm not achieved, probably atrial flutter- beta blockers etc.

Question 21

Broad complex tachy

Answer 21

Ventricular activation not via normal specialised conduction system

Question 22

VT

Answer 22

Ventricle activated not via His but from somewhere else in ventricle
Broad QRS, Regular

Question 23

SVT with abberancy

Answer 23

Broad complex QRS
Supraventricular tachy, with bundle branch block (cause of broadness)
Activated by His purkinje system that’s not working as it should

Question 24

Paced rhythm

Answer 24

Broad complex QRS

Question 25

Pre-excited rhythm

Answer 25

Broad complex QRS

Question 26

VT- clues ECG

Answer 26

``` Regular broad complex VA dissociation (fusion beats, capture beats, independent p wave activity) Ventricular concordance Bizarre frontal axis Very broad QRS ```

Question 27

Broad QRS irregular

Answer 27

AF with BBB | Pre-excited AF

Question 28

Complete HB

Answer 28

Complete dissociation between p waves and QRS

Question 29

Device therapy

Answer 29

Bradycardia- pacemaker Susceptibility to VT/VF- ICD (implantable cardioverting defibrillator) Cardiac resynchronisation- BiV/CRT device- works at all times, to make right and left ventricle work in conjunction

Question 30

Situations where risk of arrhythmias

Answer 30

Cardiomyopathy patients History of syncope/FH SCD (brugada syndrome, ARVC, long QT syndrome) Other medical conditions (infiltrative conditions, myotonic dystrophy)