Abnormal Heart Rhytm Flashcards
What is wrong with this ecg
Ventricular tachycardia
(Has a wide complex so if tachycardia as well chances are 90% that it is VT) normal 3-5 small boxes
Other causes of wide complex tachycardia
Difference between VT and LBBB
VT p waves
Usually AV dissociation present but seldom visible on ECG
Differentials for wide complex tachycardia
Ventricular Tachycardia (1st guess)
Supraventricular tachycardia with BBB (2nd guess)
Pre-excited tachycardia over an accessory
pathway (Antidromic AVRT)
Ventricular paced rhythm
Animation of wide complex tachycardia
Must look for if wide complex tachycardia (patient may present with the following as well)
BBB (look in v1 and v6)
WPW (delta waves)
MI (q waves present)
Narrow complex regular tachycardia differential
Sinus tachycardia
Atrial flutter
AVJRT (AVNRT, AVRT)👉🏻supraventricular tachycardias
Atrial tachycardia
Junctional ectopic tachycardia
Tachyarrhytmia
Treatment of patient coming in with tachycardia
Immediate synchronized DC cardioversion is the most
effective
Amiodarone has a low efficacy in terminating VT in the acute
setting (20-30%) and may cause hypotension
Never give verapamil or adenosine in patients with a wide
complex tachycardia
Remember: Patients with VT can be haemodynamically stable
VT in younger patients
Cause can be idiopathic
VT examinations
Structural heart diseases
Systemic diseases (sarcoidosis)
Correct electrolytes
Treatment longterm for VT patients
VT due to structural heart disease:
– Commence anti-arrhythmic drug therapy (Beta-
blocker and Amiodarone)
– Refer for implantable cardioverter defibrillator
(ICD)
– VT ablation for recurrent ICD shocks
– Tx underling cause - Immunosuppressive
treatment (sarcoidosis)
(cf Idiopathic VT: refer for radiofrequency ablation)
Implantable Cardioverter Defibrillator
Differential of transient loss of consciousness
Taking history after syncope
*Circumstance
pain, prolonged standing, cough, micturition, swallowing, during, exertion
*Prodrome
absent, palpitations, warmth, diaphoresis, sweating, nausea, ringing in the ears,
abdominal pain aura
*During the TLOC
pallor, sweating, cyanosis posturing, jerking
*Postdrome
rapid recovery or fatigue confusion
*Medication
*Family history
*History of cardiac disease
Features of different causes of syncope
*Epilepsy
Tongue biting
Tonic clonic movements/head posturing
Confusion after loc
*Vasovagal
Prodrome (sweaty, nausea, light headedness)
Situiational (prolonged standing or sitting)
*Orthostatic
Postural dizziness
*Cardiac syncope
History of structural heart disease
*Exertional syncope
No prodrome, unpredictable
Palpitations at the time of syncope
Bradycardia main questions to ask yourself
Is this an AV block (p waves without qrs complexes)
Is this a sinus bardycardia (all p waves has qrs complexes)
Look in the inferior leads to confirm this(v1,v2 and avf)
Heartblock features
More p waves than qrs complexes
Regular rhytm (look at qrs to see this)
No association between p waves and qrs
Mechanism behind bradycardias
*Impulse generation (Sinus node problem)
Sinus bradycardia
Sinus arrest
Tachy-brady syndrome
Sino-atrial exit block
*Impulse conduction (i.e. AV node or HPS
problem)
1st, 2nd, 3rd degree heart block
Causes of sinus node dysfunction
*Intrinsic (intermittent dizziness, syncope)
Sick sinus syndrome
*Extrinsic (“sick” from underling cause)
Hyperkalaemia
Hypothermia
Hypothyroidism
Hypoxia
Hypercarbia
Head injury
Hypervagotonia
Drugs
Causes of heart block
• Degenerative (by far the most common)
• Inferior STEMI
• Congenital
• Infiltrative (Sarcoid, Amyloid)
• Drugs (remember digoxin)
• Hyperthyroidism
• Connective tissue diseases
• Aortic root abscess
Sinus arrest
Heart block degrees
– 1st degree (at average node usually or his pukinje)
– 2nd degree(at av node usually or his purkinje)
• Type 1 Mobitz (Wenckebach)
• 2:1 AV block
• Type 2 Mobitz
– 3rd degree(at his purkinje usually or av node)
