Arrhythmia Flashcards
What is the most common cause of Sudden Cardiac death?
Ventricular Fibrillation
What is the most common cause of Stroke?
Atrial Fibrillation
What does the P-Wave represent?
Depolarization of the Atria
Those tisses with slower Action potentials are dependent upon what?
Calcium
How can Ventricular Hypertrophy be diagnosed on ECG?
Height of the R wave is markedly increased
T Wave reversal
What is the mechanism of the ECG abnormalities in Ventricular Hypertrophy
Increased muscle mass delays depolarization and repolarization
Is Bundle Branch Block always pathological?
Yes
What are the EKG features of Bundle Branch Block?
Wide QRS
What is the pathophysiology of Bundle Branch Block
Delayed activation of the ventricle since conduction tissue is blocked
What is the PR interval?
Conduction through the AV node
What is the RS interval
Polarization of the ventricles
What does the T wave represent?
Repolarization
What does the Q wave represent?
Septal depolarization
What are the 2 MAJOR MECHANISMS* of Cardiac ARRHYTHMIAS?
- Altered Automaticity
2. Reentry
What is Enhanced Automaticity?
Occures when there is a depolarization outside the normal cycle
What phase of the action potential has been altered in Enhanced Automaticity?
Phase 4 and it is raised threshold potential
What are possible causes of Enhanced Automaticity?
- Increases sympathetic tone
- Decreased parasympathetic tone
- CO2
- Digitalis
- Low oxygen
- Decreased Potassium
What are some causes of reentry?
Ischemia
Valve disease
Cardiac Surgery
Electrolyte Imbalance
What are some of the possible Clinical effects of Reentry?
- Premature Atrial Depolarization
- Supraventricular Tachycardia
- Ventricular Tachycardia
- Arrythmia in
What must be present for reentry to occur?
- A contiguous alternative pathway for the current to move along
- Loop circuit
- Loop circuit + Unidirectional Blocc
- Different conduction (slower) velocity
