1. Arrhythmias
Danny Haywood
FY1

2. Intro Conduction system of heart Symptoms/signs Investigations
Tachy vs Brady
Bradyarrhythmias
Different types
Management
Tachyarrhythmias
Broad vs narrow
Types of each
Management of each
Summary
Some example ECGs

4. Symptoms/signs Syncope Dizziness Palpitations Heart Failure Chest pain
Sudden death
No symptoms

5. Investigations Bedside Bloods Imaging Special tests ECG
TFTs, U+E, FBC, Troponins
Imaging
Echo, CXR
Special tests
Holter monitor

6. ARRhYTHMIAS Bradyarrhythmias vs Tachyarrhythmias Brady Tachy
HR < 60bpm
Tachy
HR > 100bpm

7. Bradyarrhythmias Type I heart block Type II heart block
1st degree heart block
Prolonged PR interval > 0.2 seconds
Type II heart block
Mobitz type 1 – Wenckebach
Gradually increased PR intervals until missed QRS
Mobitz type 2
Intermittently P wave not followed by QRS
May be pattern eg 2:1, 3:1 ratio of P waves to QRS complexes – no increase in PR interval
Type III heart block
Complete heart block
No correlation between P waves and QRS complexes

8. Management Acute (eg. Secondary to MI) Chronic
If symptomatic/clinical deterioration
IV atropine
External (transcutaneous) pacing
Chronic
Mobitz type II or complete AV block
Permanent pacemaker

9. Tachyarrhythmias
Narrow complex (Supraventricular) vs Broad complex (Ventricular)
Narrow
QRS <0.12 seconds
Broad
QRS >0.12 seconds

10. Narrow complex Sinus tachycardia Atrial Fibrillation (AF)
Atrial Flutter
Atrioventricular nodal re-entry tachycardia (AVNRT)
Atrioventricular reciprocating tachycardia (AVRT)

11. AF
Continuous, rapid activation of atria – due to rapidly depolarising foci within the atria
Often located by pulmonary veins
No coordinated mechanical action

12. AF – Causes ATRIAL PhIB A – Alcohol T – Thyroid disease
R – Rheumatic heart disease
I – Ischaemic heart disease
A – Atrial myxoma
L – Lung pathology (pneumonia, PE)
Ph – Pheochromocytoma
I – Idiopathic
B – Blood pressure (hypertension)

13. AF - management Conservative Medical Interventional Alcohol cessation
Lifestyle factors (diet/exercise/smoking)
Medical
Treat underlying cause
Rate control vs rhythm control
Interventional
Catheter ablation

14. Rate control Older age, permanent AF
Bisoprolol/verapamil and Warfarin (CHADSVASc)

15. Anticoagulation Therapy
Congestive heart failure (or Left ventricular systolic dysfunction) 1  H
Hypertension: blood pressure consistently above 140/90 mmHg (or treated hypertension on medication)
 A2
 Age ≥75 years 2  D
 Diabetes Mellitus
 S2
 Prior Stroke or TIA or thromboembolism  V
 Vascular disease (e.g. peripheral artery disease, myocardial infarction, aortic plaque)  A
 Age 65–74 years
 Sc
 Sex category (i.e. female gender)
Chadsvasc
Score
Risk
Anticoagulation Therapy
Low
No antithrombotic therapy (or Aspirin) 1
Moderate
Oral anticoagulant (or Aspirin)
2 or greater
High
Oral anticoagulant

16. Rhythm control Cardioversion < 48 hours
Pharmacological vs DC
younger, symptomatic, physically active patients
Congestive heart failure
Paroxysmal AF
failure of rate control
< 48 hours
Cardioversion + heparin
> 48hrs – TOE/anti-coagulation (3 weeks)
risk of failure?
High – 4 weeks sotalol/amiodarone then electrical.
Low - electrical

17. Rhythm control Pharmacological Interventional
No structural heart disease
1st - Flecainide
2nd – Sotalol
3rd – Amiodarone
Structural heart disease
Amiodarone
Interventional
Pulmonary vein isolation - catheter ablation

18. Atrial Flutter
Organised atrial rhythm, coming from ectopic focus in atria (usually left)
Usually 300bpm
Ventricular rate depends on degree of AV block eg 2:1 = 150bpm
Saw tooth pattern

19. Atrial Flutter Management Conservative Medical – similar to AF
Vagal manoeuvres
Medical – similar to AF
Acute
DC cardioversion or IV adenosine (<48 hours)
> 48 hours - 3 weeks anticoag then cardiovert
Chronic
Pill in pocket
Regular anti-arrhythmics
Interventional
Radiofrequency catheter ablation

20. AVNRT 2 pathways within the AV node
1) short refractory period + slow conduction
2) long refractory period + fast conduction
Normally conducts through fast pathway
If premature atrial beat, fast pathway still refractory (long refractory period) therefore travels down slow pathway and back up the fast pathway.

21. avnrt

22. AVRT Accessory pathway (Bundle of Kent most common)
Pre-excitation (delta wave) on ECG
Wolff-Parkinson-White syndrome

23. Management of SVTs Haemodynaically unstable Conservative Medical
Electrical cardioversion
Conservative
Vagal manoeuvres
Valsalva, carotid massage, cold water
Medical
Adenosine (acute)
Anti-arrhythmics (regular and pill-in-pocket)
Interventional
Catheter ablation

24. Broad complex tachys VT vs VF
Unstable
electrical cardioversion
Stable
1st – Class I Anti-arrhythmics (lidocaine)
2nd – Amiodarone
3rd – DC cardioversion

25. Broad complex tachys VT vs VF
Cardiac arrest
Rapid, irregular activity – no cardiac output
Usually provoked by ventricular ectopic beat
Management
Electrical defibrillation

26. Broad complex tachys Something to be aware of
SVT with concomitant bundle branch block = broad complex tachy

27. Summary Brady vs tachy Remember causes of AF Brady Tachy Sinus Brady
1st degree heart block
Mobitz I & II
Complete
Tachy
Narrow
Sinus tachy, AF, Flutter, AVNRT, AVRT
Broad
VT, VF,
Remember causes of AF

28. ECGs – test yourself

29. A

30. B

31. C

32. D

33. E

34. F

35. G

36. H

37. I

38. J

39. K

40. L

41. Answers Sinus rhythm AF Atrial Flutter VT VF 1st degree heart block
Complete heart block
Mobitz type II
AVRT
Mobitz type I
AVNRT
Right bundle branch block

42. References All images and ECGs borrowed gratefully from google images
Kumar & Clarke: Clinical Medicine 7th Ed
NICE guidelines: AF (CG36)