lecture 3 (chapter 6 and 8) Flashcards
the biphasic P wave is characteristic of atrial enlargement, but we want to know which of the 2 ____ is enlarged
atria
a patient who has enlargement of the left atrium, because the mitral valve is stenosed, will have a biphasic P wave in lead _____
V1
with left ventricular hypertrophy there is a very tall _____ wave in lead V5
R
Characteristic T wave is commonly associated with ____ ventricular hypertrophy
left
ventricular strain is characterized by depression of the ST____-
segment
what is strain usually associated with
ventricular hypertrophy
minor AV blocks lengthen the brief pause between _______ and _______
atrial depolarization and ventricular repolarization
describe a third degree AV block
completely blocks the conduction of atrial stimuli to the ventricles
the delay caused by a first degree AV block prolongs the _____
PR interval
where does Wenckebach typically originate
AV node
where does mobitz originate
below the AV node
what inhibits the AV node, making it more refractory
vagal maneuvers
if ventricular rate ranges between 40 and 60, the a focus in the ________ is probably pacing the ventricles
AV junction
the diagnosis of a bundle branch block is mainly based on ______
widened QRS
to diagnose BBB, the QRS complex must be at least _____ of a second in duration
0.12
what type of disorder is sinus node dysfunction
bradyarrhythmias (disorders of impulse formation)
what type of disorder is sick-sinus syndrome
disorder of impulse formation (bradyarrhythmias)
what are the criteria for first degree AV block
1-to-1 ratio of P waves to QRS complexes, PR interval is fixed/consistent, PR interval exceeds 200 sec (must meet all 3)
what are the 2 types of Type 1 second degree AV block present
grouped beats (groups are clusters of QRS complexes separated by missed single beats) or 2 P waves for every QRS complex, without groups or clusters of beats (all PR intervals will be the same)
