Abnormal ECG Flashcards
Rhythm arising from the SA node, Atrium or AV node are called…
Supraventricular rhythm
How are the Supraventricular rhythms conducted and what is the consequence on ventricular depolarisation?
- By His-Purkinje system
- Normalventricular depolarisation ,normal narrow QRS
Where do ventricular rhythms arise from and how do they spread ?
What do QRS look like ?
- From different foci in ventricle
- DONT spread via His-Purkinje system
- Wide QRS (>3 small boxes)
What do atrial beats look like on ECG ?
- Small p wave
- Normal QRS
What can you see on a AV junctional beat ECG ?
Reversed p wave because atrial depolarisation goes away from apex (AV to SA)
Normal QRS
Which lead is the best to look at p waves ?
II
What is normal sinus rhythm ?
- HR 60-100 bpm
- Regular
- p wave befor each QRS
- PR 0,12-0,20 s
- QRS < 0,12 s (3 small boxes)
Sinus rhythm with rate < 60bpm is called …
Bradycardia
What causes Atrial Fibrillation ?
Multiple atrial foci , chaotic impulses
What are the consequences of AF on the P wave , impulse and QRS ?
- No p wave , wavy baseline
- Impulses arrive at AV node at rapid irregular rate
- QRS normal but irregular
In AF, are all impulses arriving at the AV node conducted ? Why
No,
only some at irregular intervals because AV node in refractory period
How is the pulse and HR in AF ?
Irregularly irregular
What is Heart block ?
AV conduction blocks
-Delay or failure of impulse conduction from atrium to ventricle via AV node and bundle of HIS
What can cause heart block ?
Acute MI
Degenerative changes
What are the 3 types of heart block ?
- First degree
- 2nd degree
- -type 1 : Wenkenbach
- -type 2
- 3rd degree , Complete heart block