Arrhythmia

Front 1

SA Node blood supply

Back 1

RCA (55%)

Left circumflex (45%)

Front 2

Normal Heart rates of different intrinsic pacemakers

Back 2

SA Node: 60-90 bpm

AV Node: 45-60 bpm

His-Prkinje/BB Fibers: 30-45bpm

Front 3

AV Nodal Blood supply

Back 3

RCA (90%)

Left circumflex (10%)

Front 4

Blood supply of Bundle Branches

Back 4

RBB: LAD

LAF: LAD

LPF: RCA or Left circumflex

Front 5

Mechanisms of DYSRHYTHMIA

Back 5

(1) Increased automaticity

(2) Triggered activity

- Early Afterpolarizations

- Late Afterpolarizations

(3) Reentry circuits

- Two paths, one with a relatively slower refractory period

Front 6

Action of myocardial cell and relation to ion flow

Back 6

Front 7

Overview of Anti-Arrhythmics

Back 7

Front 8

Effect of of Anti-Arrhythmics on ECG intervals

Back 8

Front 9

Adverse effects of Amiodarone

Back 9

Acute Effects
Hypotension
Slowing of heart rate
Decreased contractility

Long-Term Effects

Common
Corneal deposits
Photosensitivity
Gastrointestinal intolerance

Less Common
Hyperthyroidism
Heart failure
Pulmonary toxicity, fibrosis
Hypothyroidism
Bradycardia
Prodysrhythmic effect

Drug Interactions
Increase Levels
- Phenytoin
- Procainamide
- Warfarin
- Digoxin
- Flecainide

Front 10

Electrophysiological effects of digoxin

Back 10

Front 11

Causes of sinus bradycardia

Back 11

Pharmacological

• Beta-blockers
• Calcium-channel blockers
• Digoxin
• Central alpha-2 agonists
• Amiodarone
• Opiates
• GABA-ergic agents
• Organophosphate poisoning

Non-pharmacological

• Normal during sleep
• Increased vagal tone (e.g. athletes)
• Vagal stimulation (e.g. pain)
• Inferior myocardial infarction
• Sinus node disease
• Hypothyroidism
• Hypothermia
• Anorexia nervosa
• Electrolyte abnormalities – hyperkalaemia, hypermagnesaemia
• Brainstem herniation (the Cushing reflex)
• Myocarditis

Front 12

Differential Diagnosis of causes of bradycardia

Back 12

• Cardiac disease
  • Myocardial ischaemia / infarction
  • Myocarditis
  • Congenital disorders
  • Cardiomyopathies
  • His-Purkinje fibre degeneration
• Hypoxia
• Electrolyte disturbance (e.g. hyperkalemia)
• Medications, poisonings and toxic exposures (e.g. digoxin, beta blockers, calcium channel blockers, amiodarone, clonidine, organophosphates)
• Hypothermia
• Hypothyroidism
• Raised intracranial pressure (Cushing response)
• Infections (e.g. Lyme disease, diphtheria, typhoid fever)
• Autoimmune (e.g. systemic lupus erythematosis)
• Infiltrative disorders (e.g. sarcoidosis, amyloidosis)
• Physiological causes (e.g. athletes, vagal stimuli)

Front 13

Differential of regular vs irregular bradycardia

Back 13

Regular
Sinus bradycardia
Junctional bradycardia/Idioventricular
Complete AV block (junctional escape)
Atrial flutter with high degree block

Irregular
Sinus arrhythmia, pause or arrest
Sinoatrial exit block (second degree)
Atrial fibrillation with slow ventricular response
Atrial flutter with variable block
Second degree AV block, type I
Second degree AV block, type II

Front 14

Sick Sinus Syndrome

Back 14

group of dysrhythmias from disease
of the sinus node and its surrounding tissues,including sinus bradycardia, sinus arrest, and SA exit block

Front 15

Type I vs Type II AV BLOCK

Back 15

Front 16

Bigeminy

Back 16

Extrasystole after every native beat

Front 17

Ashman phenomenon

Back 17

wide complex QRS complexes that follow a short R-R interval preceded by a long R-R interval

This wide QRS complex represents an aberrantly conducted complex that originates above the AV node

occurs because the duration of the refractory period of the myocardium is proportional to the R-R interval of the preceding cycle

Front 18

PAC vs PVC

Back 18

Front 19

Cause of PVCs and Vtach

Back 19

Acute or previous myocardial infarction or ischemia
Hypokalemia
Hypoxemia
Ischemic heart disease
Valvular disease
Catecholamine excess*
Other drug intoxications (especially cyclic antidepressants)
Idiopathic causes†
Digitalis toxicity
Hypomagnesemia
Hypercapnia
Class I antidysrhythmic agents
Ethanol
Myocardial contusion
Cardiomyopathy
Acidosis
Alkalosis
Methylxanthine toxicity

Front 20

Tachycardia Algorithim

Back 20

Front 21

Causes of sinus tachycardia

Back 21

Drugs/Meds/Iatrogenic

Anticholinergic

Catecholamines

Alcohol

Caffeine

Tobacco

Cocaine

β-blocker withdrawal

Supraventricular tachycardia ablation

Medical

Anemia

Dehydration

Exercise

Anxiety

Pain

Pulmonary embolus

Fever

Infection

Pericarditis

Aortic or mitral regurgitation

Myocardial infarction

Pneumothorax

Hyperthyroidism

Hypoglycemia

Front 22

Potential Causes of A Fib

Back 22

Cardiac causes
Hypertension
Heart failure
Coronary artery disease/ prior MI
LV Dysfunction
Cardiomyopathies
Valvular heart disease
Congenital heart disease
Pericardial disease
Postsurgical (particularly cardiac surgery)
Sick sinus syndrome
AF as a result of ventricular pacing
Supraventricular tachycardia (including WPW, atrial tachycardia, a flutter, ect)
Genetic/familial

Noncardiac causes
OSA
Obesity
Excessive alcohol ingestion
Hyperthyroidism
Pulmonary disease (pneumonia, COPD, PE, Pulm HTN)
Lone (idiopathic) AF

Front 23

2014 CCS Algorithim for who needs anticoagulation with a fib

Back 23

Front 24

Relative risk reduction for stroke in patients with afib:

- ASA

- Wargarin

Back 24

ASA: 22% (NNT = 34)

Warfarin: 64% (NNT = 14)

Front 25

CVA risk at different CHADS2 scores

Back 25

0: 1.9

1: 2.8

2: 4.0

3: 5.9

4: 8.5

5: 12.5

6: 18.2

Front 26

2014 CCS reccomendations regarding OACs

Back 26

(1) for OAC with nonvalvular AF, dabigatran, rivaroxaban or apixaban in preference to warfarin

(2) for OAC patients with a mechanical prosthetic valve, rheumatic mitral stenosis or eGFR of 15-30 ml warfarin is prefered over NOACs

(3) Consider lower dose age >75 and CRF

Front 27

CCS ED algorithim for management of A Fib

Back 27

Front 28

AVRT with orthodromic conduction (AV node 1st)

Back 28

• Rate usually 200 – 300 bpm
• P waves may be buried in QRS complex or retrograde
• QRS Complex usually <120 ms unless pre-existing bundle branch block, or rate-related aberrant conduction
• QRS Alternans – phasic variation in QRS amplitude associated with AVNRT and AVRT, distinguished from electrical alternans by a normal QRS amplitude
• T wave inversion common
• ST segment depression

Front 29

AVRT with antidromic conduction (bypass 1st)

Back 29

• Rate usually 200 – 300 bpm.
• Wide QRS complexes due to abnormal ventricular depolarisation via accessory pathway

Front 30

Diseases associated with WPW

Back 30

Idiopathic*
Cardiomyopathy (especially hypertrophic)
Transposition of great vessels
Endocardial fibroelastosis
Mitral valve prolapse
Tricuspid atresia
Ebstein’s disease

Front 31

SVT with aberrancy versus VT

Back 31

Front 32

Criteria for Torsade de Pointes

Back 32

1. Ventricular rate greater than 200 beats/min
2. Undulating QRS axis, with the polarity of the complexes
appearing to shift about the baseline
3. Paroxysms of less than 90 seconds

Front 33

Classification of Conditions that can lead to to Torsade de Pointes

Back 33

Pause Dependent (Acquired)
Drug induced: Class IA and IC antidysrhythmics; many phenothiazines and butyrophenones (notably haloperidol and
droperidol), cyclic antidepressants, antibiotics (especially macrolides), organophosphates, antihistamines, antifungals,
antiseizure and antiemetic agents
Electrolyte abnormalities: hypokalemia, hypomagnesemia, hypocalcemia (rarely)
Diet related: starvation, low protein
Severe bradycardia or atrioventricular block
Hypothyroidism
Contrast injection
Cerebrovascular accident (especially intraparenchymal)
Myocardial ischemia

Adrenergic Dependent (Tachycardia Prompted)
Congenital
Jervell and Lange-Nielsen syndrome (deafness, autosomal recessive)
Romano-Ward syndrome (normal hearing, autosomal dominant)
Sporadic (normal hearing, no familial tendency)
Mitral valve prolapse
Acquired (Rare)
Cerebrovascular disease (especially subarachnoid hemorrhage)
Autonomic surgery: radical neck dissection, carotid endarterectomy, truncal vagotomy

Front 34

Rx for Torsade de Pointes (acquired)

Back 34

Empiric magnesium

D/C any QT pronlonging agents

Correct Electrolyte abnormalities

Increased HR to shorten QT

Front 35

Ainsworth SVT vs VT

Back 35

Front 36

ECG Findings to search for in syncope

Back 36

(1) Acute coronary syndrome
(2) Tachycardia/Bradycardia and AV blocks
(3) Intervals
- Short PR suggesting WPW/Pre-excitation
- Long or Short QT interval
(4) Hypertrophic cardiomyopathy
(5) Brugada syndrome
(6) Arrhythmogenic right ventricular dysplasia

Front 37

Critical diagnoses to consider in patient with syncope

Back 37

Life threatining dysrhythmias

Myocardial infarction

Outflow obstruction

Critical aortic stenosis

PE

Pericardial tamponade

Hypertrophic cardiomyopathy

Vascular catastrophes

SAH

Thoracic aortic dissection

Abdominal aortic aneurysm

Ectopic pregnancy

Hypovolemia/Hemorrhage/Anemia

Toxic/Metabolic derangements

Stroke