Test 3 - Chapter 25 - Arrythmia

lebohese's version from 2018-03-28 01:53


Question Answer
Normal heart rate is between ___ and ___/minute60 &100
Heart contractions occur when cardiac cells "fire" known as depolarization
During depolarization, ____ charged ions enter the cells through specialized exchange channelspositively
___ initiates depolarization of the atria and ventriclesNa+
___ entry results in depolarization of the sinoatrial (SA) and atrioventricular (AV) nodesCa+
The cells must return to their resting state also known asrepolarization
The time it takes for repolarization to occur is know as refractory period
How do arrythmia's occur?the cardiac ion exchange channels function improperly
What is an arrythmia?an irregular heart rhythm or heart rate that is too rapid/too slow
Atrial flutter is a heart rate of 160-350 beats/min. It is caused by more contractions in the ___ than in the ___.atrium & ventricle
Supraventricular tachycardia (SVT) is a heart rate of____up to 200 beats/min
Ventricular tachycardia is a heart rate of____faster than 200 beats/min
Atrial fibrillation is a heart rate of 300 - 400 beats/min
What is the most common arrythmia?Atrial fibrialltion
Ventricular fibrillation is a heart rate of faster than 600 beats/min
Antiarrythmic drugs are classified into ____ classes4
MOA: Class l - Na+ channel blockers Slow rate of depolarization/prolong time between contractions
MOA: Class ll - B-Blockerssuppressing ectopic beats and arrythmia's/ blocking stimulation of the SV and AV nodes
MOA: Class lll - K+ channel blockersblockade of potassium channels/prolong depolarization and refractory period
MOA: Class lV - Ca2+ Channel blockersCa2+ Channel blockade
Cardioglycosides is approved for the treatment of ___atrial fibrillation
MOA of Cardioglycosidesslows conduction velocity and prolongs refractory period
ACEI's and ARB's both lengthen refractory period and shorten ____conduction time
What kind of fibrillation is life threatening?Ventricular fibrillation