physiology lab exam 2 part3

p wave

atrial depolarization

QRS complex

ventricular depolarization

T wave

ventricular repolarization

PR or PQ interval

atrial conduction

QT interval

ventricular conduction

RR interval

heart rate

ST segment

ventricular de/re time

sinus bradhycardia (normal rythm)

sinus rhythm rate less than 60bpm

sinus tachycardia (normal rythm)

sinus rhythm greater than 100bpm

supraventricular tachycardia (not normal)

P and t waves are together instead of separate- P waves essentially absent in SVT

Atrial flutter (a-flutter)

consecutive atrial depolarization waves or "flutter" waves

- "saw tooth" appearance

-different ratios (2:1, 3:1, 4:1) possible

atrial fibrillation (a-fib)

-cause by many ectopic trial foci firing at rapid rates

-no distinguishable p waves because the atria are sending impulses erratically

-variable and irregular QRS response

ventricular tachycardia (v-tach)

-characteristic wide QRS complexes

-P wave generally blends within the QRS

ventricular fibrillation (v-fib)

-ventricular fibrillation is a type of cardiac arrest. There is no effective pumping action by the heart and there is no circulation

-lack of any identifiable waves on the electrocardiogram; it appears as erratic, rapid twitching of the ventricles

-requires immediate cpr and defibrillation