Bradycardia Assessment and Management

Bradycardia Assessment and Management

1. Bradycardia
Assessment and Management
Callum Addison

2. ●Narrow Complex:
●Wide Complex
Classifying Bradydysrhythmias
Regular Irregular
Sinus bradycardia Sinus arrhythmia
Complete AV Block
(junctional escape)
Mobitz Type I+2
Atrial flutter with high
degree block
Atrial flutter with variable
block.
Regular Irregular
Sinoventricular
rhythm
Sinoatrial exit block
with BBB
Complete AV Block
(ventricular escape)
Mobitz Type I+2
Atrial flutter with high
degree block
Irregular
bradycardias with
BBB

3. ECG 1
●Type II

4. ECG 2

5. ECG 3

6. Classification (cont)
●Sinus Bradycardia
●Sinus node dysfunction
Sinoatrial exit block
Sinus arrest – pause > 3 seconds
●Sick sinus syndrome.
●AV
1
st
degree HB
2
nd
degree HB – Mobitz I + II
3
rd
degree HB
Junctional escape
●Ventricular escape rhythm

7. Causes
●Physiological
●Medications – AV nodal blockade, cholinergic crisis
●Cardiac disease – Ischaemia, myocarditis, cardiomyopathies, HIS-
purkinje fibre degeneration
●Metabolic/Endocrine – Anorexia, hyperkalaemia, hypothyroidism
●Neurological
●Autoimmune – SLE, sarcoidosis, amyloidosis
●Infections – Lyme disease, diptheria, typhoid fever
●Hypoxia/Hypothermia
●Surgery

8. Sinus Bradycardia
●Physiological
Athletes
Respiratory Sinus Arrhythmia
Sleep:

10. Medications
●AV nodal blocking drugs
(Class II, Class IV, Digoxin, Amiodarone)
●Organophosphates
●Clonidine
●Spot Quiz – Which organophosphate was recently
used to assassinate the step-brother of a well known
political figure.

11. Kim Jong-nam - VX

12. Ischaemia
●Up to 30% of patient with inferior STEMI will
develop second or third degree AV block.
●Associated with an increased in-hospital mortality.
●Inferior myocardial wall and the SA/AV nodes are
usually all supplied by the right coronary artery

13. Raised ICP
●Cushing response.
● Raised BP, Bradycardia, Irregular breathing.
●Bradycardia is due to the baroreceptor response to
the sympathetic efforts to increase cerebral
perfusion – or mechanical distortion of the vagus
nerve

14. Symptomatic
Dizziness, light headedness, palpitations, fatigue,
exercise intolerance.
Unstable
● Neuro: GCS, Syncope
● Respiratory: SOB, Pulmonary congestion
● CVS: Hypotension, shock, CHF, ACS.
Symptoms

15. Treatment Algorithm
●ABC Management
●IV Access/O2/Vitals/ECG
●Assess for and treat underlying causes
●As per ACLS

16. ACLS Algorithm
ncreases firing of the SA Node by blocking the action of the vagus nerv

17. APLS algorithm

18. Atropine
●Competitive muscarinic antagonist -
Anticholinesterase inhibitor
●Increases firing of the SA Node by blocking the
action of the vagus nerve.
●Onset of action ~ 1 minute
●Duration of action 30 – 60 minutes.
●The first drug of choice for symptomatic
bradycardia.
●Dose in the Bradycardia ACLS algorithm is 0.5mg
IV push and may repeat up to a total dose of 3mg.

19. Spot Quiz – Who Am I
●Invasive Pest
●Solanaceae family
●Contains Tropane alkaloids

20. Transcutaneous Pacing
●Non-invasive pacing is used on a temporary basis
until the patient is stabilized and either an adequate
intrinsic rhythm has returned or a transvenous
pacemaker is inserted, whether temporary or
permanent.

21. Apple of Sodom

22. Alternative Agents
●Adrenaline (second line agent).
Non-selective A/B agonist.
2-10mcg/min
Titrated to maintain a satisfactory HR.
●Dopamine – 2-10mcg/kg/min
●Isoprenaline – 2.5mcg/min

23. Transcutaneous Pacing
●Indications
Patient with symptomatic bradycardia and a palpable pulse
who has not responded to pharmacological therapy (or no
IV access able to be established).
High-grade AV blockade (3
rd
degree heart block or unstable
mobitz type II.
Cardiac arrest with ventricular standstill, but atrial activity
present.
●Recent asystole.
●Contraindication
Asystolic cardiac arrest

24. Transcutaneous Pacing
●For pacing readiness (i.e. standby mode) in the
setting of acute myocardial infarction (AMI) with
the following:
Symptomatic sinus bradycardia
Mobitz type II second-degree AV block
Third-degree AV block
New left, right or alternating bundle branch block or
bifascicular block

25. Transcutaneous Pacing - Procedure
●O2 and IV Access.
●Sedation unless contraindicated.
●Placement of pads on clean, dry, shaven skin.
●Pacing mode with rate 60-80 bpm.
●Begin pacing at 5mA amp, increase amperage in
5mA increments until visible electrical capture-
(QRS-T complexes after each pacing spike).
●Check pulse for mechanical capture.
● Increase by a further 5mA after capture.

26. Classification of Bradycardia
●Absolute or Relative
●Functional or relative bradycardia occurs when a patient may have a heart rate
within normal sinus range, but the heart rate is insufficient for the patients
condition. An example would be a patient with an heart rate of 80 bpm when they
are experiencing septic shock.
●Narrow or Wide Complex
●Regular or irregular
●Sinus vs Sick Sinus vs AV nodal vs Ventricular

27. Case 1
●68 year old female.
●Presents with an episode of syncope on a
background of 1 week of vomiting and poor oral
intake.
●GCS 14 on arrival, HR 34, BP 80/53
●PMHx: HTN, CHF
●Medx: Spironolactone, Bisoprolol.

28. Case 1 (cont)
●K+ of 7.8
●Responded to IV calcium gluconate, IV insulin
dextrose and inhaled salbutamol.
●Always consider the diagnosis of hyperkalaemia in
patients presenting with bradycardia or complete
heart block.
).

29. Case 1 (cont)

30. Case 1 (cont)
●Severe bradycardia (HR ~ 30 bpm)
●Symmetrically peaked T waves in V2-5
●Flattening, broadening and near-disappearance of P
waves (still barely visible in V1-3)
●Prolongation of the PR interval
●Broad QRS complexes (~120 ms)

31. Case 2
●48 year old presents with sharp pleuritic
chest pain after playing a game of squash
today.
●PMHx: BPH, Meningioma.
●Fhx: CAD.
●No recent immobilization or surgical history.
●O/E Haemodynamically stable WNL. 3
rd

heart sound heard.

32. Athlete's Heart
●Regular physical activity leads to physiological
adaptions in cardiac dimensions. Primarily LV wall
thickness and cavity size.
●Enhanced diastolic filling with increased stroke
volume and cardiac output.
●Subsequent bradycardia, repolarization
abnormalities and voltage criteria for chamber
enlargement.
●Accentuated antagonism.

33. Case 2

34. Athlete's heart.
●Electrocardiographic findings that are common,
training-related, normalize with exercise and that do
not require additional evaluation are:
●Sinus bradycardia
●1° atrioventricular block or mobitz 1 are common.
●Incomplete right bundle branch block (BBB)
●Early repolarization.
●Isolated voltage criteria for left ventricular
hypertrophy (LVH).

35. Athlete's Heart (cont)
● With voltage criteria for LVH, pathological
hypertrophy should be suspected in any of the
following:
●Left atrial enlargement,
●Left-axis deviation,
●Repolarization abnormalities,
●Pathological Q waves.
●T-wave inversion ≥2 mm in ≥2 adjacent leads.

36. Proceed with caution.

37. Case 3
●74 year old lady with sudden onset 30 minute
episode of crushing central chest pain, radiating to
neck and associated with diaphoresis and
palpitations.
●Previous similar episodes for the last 6 months on
exertion however only mild in severity.
●PMHx: Diabetic, HTN, Hypercholesterolaemia.
●Shx: Smoker
●O/E – HR 42, BP 102/60, Sats 97% on RA.

38. Case 3 (cont)

39. Case 3 (cont)
●Regular, narrow complex bradycardia.
●Ventricular rate of 43 BPM.
●Complete AV block.
●Likely junctional escape rhythm.
●Significant ST elevation in leads II, III, and AVF,
with reciprocal ST depression in leads I and AVL,
all suggestive of an inferior STEMI.

40. Case 3 (cont)
●Inferior STEMI with RV infarction was diagnosed.
● IV fluids were given.
● Aspirin, Ticagrelor and Heparin were given
● Patient taken to cath lab:
●Coronary angiography revealed an acute thrombus
with 100% occlusion of the proximal Right
Coronary Artery (proximal to the right ventricular
marginal branch), successfully stented and reduced.

41. Summary
●Remember ABC'ss
●Assess and treat underlying causes
●Reassess regularly for changes in rhythm.
●Decision to treat largely based on
haemodynamic stability and risk of asystole.
●Clear algorithms provided by APLS/ACLS
available for treatment.

42. LIFEPAK 20/20E Defibrillator/Monitor
Noninvasive (Transcutaneous) Pacing
Demonstration video (4 minutes).
●https://www.youtube.com/watch?
v=Nb0fDABC6UY

43. References/Further Reading
●ACLS/APLS Australia
●Australian Resuscitation Council
●Textbook of Cardiology.org
●Family Practice Notebook
●LITFL
●Dr Smith's ECG Blog
●Dr Venkatesan.com
●Department of Agriculture and Food.