ECG PA: Rhythm abnormalities Flashcards
What are the ECG correlates of sinus arrhythmia?
- One P wave per QRS complex
- Constant PR interval
- Progressive beat-to-beat change in the R–R interval.
aetiologies of Sinus bradycardia?
athletic training, fainting attacks, hypothermia or myxoedema, and is
also often seen immediately after a heart attack.
Supraventricular rhythms consists of ?
Sinus rhythm
Atrial rhythm
Junctional or nodal rhythm
Narrow QRS seen in ?
Supra-ventricular rhythms
Wider QRS seen in
Ventricular rhythms + supra-ventricular rhythms with BBBs or WPW syndrome.
SA node rate average is ?
70
Atrial ectopic focus and AV node average rate ?
50
Ventricular rhythms ?
30
Significance and mechanism of escape rhythms ?
- They are often protective as they occur in the context of SA nodal failure and they should not be aborted as they are essential for the heart.
-They are commonly seen in acute phase of MI.
ECG correlate of atrial escape ?
after a series of normal SA P waves an abnormal P wave emerges which is followed by a normal QRS which is followed by normal P-QRS.
ECG correlates of junctional rhythms ?
- rate about 75 BPM
- No P waves
-often normal QRS or deep SS pattern.
ECG correlates of ventricular escape ?
- AV rate dissociation ( Atrial rate = 145 BPM, Ventricular rate = 15BPM)
- Many P waves between QRS
- wired QRS morphology with T wave inversions.
What should be the minimum rate in diagnosing V-TAC ?
V-Tac should not be diagnosed if the rate is not > 120.
What is accelerated
idioventricular rhythm ?
It is a benign condition seen in the context of ventricular escape rhythms . It is caused by a ventricular focus taking control of the ventricular rate paroxysmally.
It should not be treated unless the HR exceeds > 120 beats / min.
Extrasystole ECG pattern ?
Atrial extrasystole = abnormal P wave
Junctional = no P wave or immediatly before or immediatly after the QRS.
