Flashcards in ECGs: Tachycardias Deck (30)
what murmurs cause AF?
irregularly irregular rhythm should immediately cause you to think
pathology of atrial flutter?
AV nodal reentry circuit
why is there increased risk of stroke in AF?
disordered blood flow in the atrium causes it to pool and form a clot which can travel to the brain
what are the QRS complexes like in atrial flutter?
ECG shows a long PR interval with no other abnormalities
1st degree heart block
ECG shows an increasing PR interval with each beat followed by a dropped beat
mobitz type 1
atria are fluttering at ___bpm in atrial flutter
what drug can be given to make atrial flutter more prominently seen on the ECG?
a narrow QRS is less than ___ms
broad QRS complexes are generated from...
within the ventricle
conducted with aberrancy (not using the his-purkinje system)
a narrow complex rhythm
at or above the AV node
will be using the His-Purkinje system
commonest cause of SVT
AV nodal reentry tachycardia (AVNRT)
what happens in AVNRT
an ectopic beat signals around the atrium whilst telling the ventricle to beat
what does adenosine do?
blocks conduction through the AV node so stops the reentry circuit
difference between AVNRT and atrial flutter?
AVNRT: reentry circuit occurs in the AV node only
flutter: reentry circuit originates in the WHOLE atrium
where's the problem in AVRT?
an accessory pathway AFTER the normal pathway where the signal goes BACK to the AV node
adenosine works for AVRT T/F
blocks AV node firing so will prevent the signal coming back
how to tell if a lead is pointing negative or positive if it's hard to tell?
look for the sharpest point on the wave (eg sharp point at the bottom would be a negative lead)
if patient is clinically unstable and has a SVT what do you do?
delta waves indicate...
what does a delta wave look like and where is it?
1. a slurred upstroke on the QRS
2. short PR interval
there is no AV nodal delay in AVRT T or F
ventricles can't relax
AF + accessory pathway (eg WPW) =
a p wave found within the QRS complex is found in what supraventricular rhythm?
if a p wave is found within the QRS complex what has happened?
impulse starts in AV node instead of SA node which causes a simultaneous impulse to both the atria and ventricles
2 main pathologies behind SVT?
1. AV node reentry eg atrial flutter
2. accessory pathways eg WPW
an ECG that is sinus rhythm but the p wave looks different time is an example of
supraventricular ectopic beats