Rate Flashcards
When reading an EKG you should first consider the
Rate
Sinus rhythm
60-100 bpm
Sinus bradycardia
Rate less than 60 bpm
Sinus tachycardia
Rate more than 100 bpm
Automaticity foci
SA node, AV junction, Ventricles
Junction foci inherent rate
40-60
Ventricular foci inherent rate
20-40 beats per min
Rapid automaticity suppresses slower automaticity this is called
Overdrive suppression
An automaticity focus only emerges to function as a pacemaker when it is no longer
Overdrive suppressed
If SA node pacing failed, what can take over the active pacemaking responsibilty at its inherent rate of 60-80 bpm
An alternate atrial automaticity focus
An automaticity focus in the AV junction begins active backup pacing only
In the absence of pacing stimuli coming down from the atria
Because the AV node is the only conduction link between the atria and the ventricular conduction system, a complete block of the proximal AV node
Blocks all pacing stimuli from atrial automaticity focus
In an emergency, an irritable focus may suddenly discharge at a rapid rate of
150-250 bpm, this is the same for all foci
An R on a heavy black line is known as the start line, the dark lines after that are called the
300, 150, 100, 75, 60, 50
The distance between the heavy black lines represents
1/300th
