Tachycardia Flashcards
Tachyarrhythmia presentation
asymptomatic
SOB
palpitations
pre-syncope
chest pain
collapse
cardiac arrest
What is a palpitation?
abnormal awareness of heartbeat (not necessarily an abnormal heartbeat)
What questions should you consider when you are presented with a tachyarrhythmia?
fast or sloe
broad or narrow QRS
regular or irregular
are there P waves
AF ECG
narrow complex
irregularly irregular
no organised P waves
irregular baseline
Define tachycardia
heart rate > 100bpm
List some narrow complex tachycardias
<120ms
sinus tachycardia
AF
atrial flutter
focal atrial tachycardia
AVNRT
AVRT
List some broad complex tachycardias
ventricular tachycardia
‘SVT’ with aberrations
pre-excited tachycardia
pacemaker-associated tachycardia
What is the typical rate of atrial flutter?
150bpm
(normally an exact division of 300)
Atrial flutter ECG
narrow complex
regular
organised atrial activity
‘sawtooth’ appearance
Adenosine MOA
blocks AV node
AVNRT ECG
atrioventricular nodal reentry tachycardia
inverted retrograde P wave
(no normal P waves)
carotid sinus pressure may cause reversion to sinus rhythm
rate usually 150-180 bpm
narrow QRS
Wolff-Parkinson-White ECG
short PR interval (<120ms)
broad QRS
delta wave (slurred upstroke to QRS complex)
[pre-excitation syndrome]
What is an accessory pathway?
an extra piece of heart muscle tissue that connects directly between the atria and the ventricles, bypassing the AV node altogether
How do accessory pathways show on ECG in sinus rhythm?
broad QRS + pre-excitation (delta waves)
w do accessory pathways show on ECG in tachycardia?
narrow QRS + no pre-excitation