In lead II, what is the deflection of the P wave?
wat is considered abnormal in a P wave that occurs?
when it occurs outside SA node; in damaged atria and such
what does a notched, wide (enlarged) or biphasic P wave mean?
increased left atrial pressure and left arial dilation
three times the P wave will look different than with sinus p wave
-Premature atrial complexes (PAC's)
-Wandering Atrial Pacemaker
premature atrial complex; p wave differs in appearance from underlying rhythm (not consistent P waves)
-premature beats are occurring in the atria
wandering atrial pacemaker
P' waves continuously change in their appearance
the closer the site of origin of the P wave.....?
the more it looks like a normal P wave
if the P' wave is initiated from the middle of the right atrium...
the P' wave is less positive than one that originates from the upper-right atrium
with av heart block, do the p waves look similar or different?
alike, and the p-p intervals remain constant
with premature beats the P' wave looks...
different than regular P waves, for instance the P'-P interval is shorter
between 150-250 bpm, this results from an ectopic site in the atria. The P' wave is likely to be buried in the T wave of the preceding beat
what are t waves often like when the p' wave is buring in it because of atrial tachycardia?
the t waves are often peaked, notched, or larger than normal
what do P' waves that continuously change in appearance indicate?
that the impulse is arising from different locations in the atria (wandering atrial pacemaker)
250-350 bpm, and the normal p waves are absent, instead there are flutter waves
a chaotic looking baseline absent of uniform P waves is characteristic of atrial fib. Instead of p waves, we see an uneven baseline of f waves
when is a p' wave inverted?
when the p' wave arises from the lower right atrium near the av node, in the left atria or the av junction; results in retrograde depolarization of the atria
in 2nd degree AV heart block type I...
the AV node fatigues more with each conducted impulse until it finally is so tired that it fails to conduct an impulse through to the ventricles
in 2nd degree AV heart block type II...
there are more P waves than QRS complexes as some of the sinus waves are blocked in the AV node and do not reach the ventricles
3rd degree av heart block...
There is complete blockage of the AV node resulting in the atria being stimulated to contract by the impulse that originates from the SA node and the ventricles being stimulated to contract by an escape pacemaker that arises from somewhere below the AV node. For this reason, the atria and ventricles fire at different rates causing the P waves to appear as though they are marching through the QRS complexes