Arrhythmias Flashcards
(27 cards)
Arrhythmias
Interruption to the normal electrical signals that coordinate conduction of the heart muscle.
Narrow Complex Tachycardia
QRS < 0.12 seconds. (3 small squares)
>100Bpm
Types of narrow complex tachycardia
Sinus tachy
Supraventricular
AFib
Atrial Flutter
Red flags within narrow complex tachycardia
Treat with DC Cardioversion + / - IV Amiodarone.
LOC
Chest pain
Shock
Severe HF
Broad complex tachycardia
QRS > 0.12 seconds. (3 small squares)
>100bpm
Types of broad complex tachycardia
Ventricular Tachycardia
Polymorphic Ventricular Tachycardia (Torsades des pointes)
Afib with BBB
Supraventricular Tachycardia with BBB
Supraventricular tachycardia
Looks like there are no P waves as it looks like T wave, QRS, T wave etc.
Regular rhythm and absence of sawtooth pattern.
Idiopathic at first.
Afib
Absent P waves and irregularly irregular rhythm.
Atrial Flutter
Atrial rate at 300 bpm - sawtooth pattern
QRS occurs at regular intervals - May lead to 2 atria contractions for every one ventricular.
Re-entrant rhythm in either atrium leading to self perpetuating loop.
Repeated P waves with narrow complex tachycardia.
Treatment - Anticoagulation based on CHA2DS-VASc or Radiofrequency ablation.
Torsades des pointes
Height of QRS gets progressively smaller or larger than smaller etc. Seems like it is twisting round itself.
Terminates spontaneously and reverts to sinus or progresses to VT.
Prolonged QT for men and women
> 440ms for men (11 squares) or >460ms for women (11.5 squares)
Prolonged QT stage of cardiac cycle
Prolonged repolarisation of the myocytes after contraction
Causes of prolonged QT
Long QT syndrome (inherited)
Medications
Electrolyte Imbalances
Management of prolonged QT
Stopping and avoiding causative agents
Correcting electrolyte disturbances
Beta Blockers
Pacemakers or implantable cardioverter defibrillators.
Emergency Management of prolonged QT
Correct underlying
Magnesium Infusion
Defibrillation if VT occurs.
Medication that causes prolonged QT
Antipsychotics
Citalopram
Flecainide
Sotalol
Amiodarone
Macrolide Abx
Electrolyte imbalances causing prolonged QT
Hypokalaemia
Hypomagnesaemia
Hypocalcaemia.
Ventricular ectopics
Isolated, random and abnormal with broad QRS complex on an otherwise normal ECG
Bigeminy - every other beat is an ectopic
Management
Reassurance
Specialist advice if - underlying heart condition, frequent or concerning symptoms, Fhx of heart disease or sudden death.
Beta Blockers sometimes used.
First degree HB
Persistent prolonged PR interval always followed by a QRS
Second Degree Mobitz type 1
Increasingly prolonged PR interval followed by a dropped QRS
Second degree Mobitz type 2
Normal PR interval followed by missed QRS in a repeated pattern - e.g. 3 : 1 block
Third degree HB
No correlation between p wave and QRS.
Risk of asystole.
Causes of bradycardia
Medications - Beta blockers
Heart Block
Sick Sinus Syndrome
Sick Sinus Syndrome
Dysfunction of SAN - caused by idiopathic degenerative fibrosis.
Results in sinus bradycardia, arrhythmias and prolonged pauses.
