Ventricular Tachycardia Flashcards
Why does VT occur? (2 points)
- Rapid ventricular depolarisation originating from within ventricles
- Commonly bc scarring of ventricles after MI
How is a VT seen on an ECG?
- 100+ BPM
- Broad QRS complex (120+ ms)
What are the 2 types of VT?
- Monomorphic VT
- Polymorphic VT
What are the characteristics of Monomorphic VT? (2 things)
- Wide QRS complexes (200+ ms)
- Uniform QRS morphology
What are the characteristics of Polymorphic VT? (2 things)
- Wide QRS complexes (120+ ms)
- Variable QRS morphology
What is Torsades de pointes? (3 things)
- A subtype of Polymorphic VT
- QRS complexes “twist” around isolecetric baseline
- QT prolongation
Why does Monomorphic VT have UNIFORM QRS morphology?
Bc ventricular contractions all uniform shape bc all depolarizations beginning from same spot in ventricle
Why does Polymorphic VT have VARIABLE QRS morphology?
Ventricular contractions change shape each beat bc signal begins in different areas of ventricle
What are the risk factors of VT? (4 things)
- Ventricular muscle ischaemia (we said ventricular scarring from MI)
- Structural heart disease
- Coronary artery disease
- Electrolyte abnormalities
What are the clinical features of VT? (5 things)
- Syncope / Dizziness
- SOB
- Chest pain
- Palpitations (cah is tachy)
How is the diagnosis of VT made?
ECG / cardiac monitoring
What investigations should you do for VT? (3 things)
- ECG
- Serum electrolytes
- Toxicology studies (therapeutic / recreational drug use)
What does the management option for VT depend on?
Whether there is a pulse or not
How should you a manage VT WITH a pulse but haemodynamically UNSTABLE?
Direct current cardioversion
How should a deteriorating VT patient who is haemodynamically UNSTABLE be managed? (2 things)
- Direct current cardioversion
- If fails –> IV amiodarone hydrochloride + repeat cardioversion