II
ACTIVITY 1
NSG124.10.01.01 DYSRHYTHMIA PATHOPHYSIOLOGY & MANAGEMENT
ELECTROCARDIOGRAM (ECG)
Graphic representation of cardiac electrical activity
Previous
Play
Next
Rewind 10 seconds
Move forward 10 seconds
Unmute
0:12
/
0:15
Full screen
Brainpower
Read More
P WAVE
Caused by depolarization in the atria and corresponds to atrial contraction
BRADYDYSARHYTHMIAS
dysrhythmias in which heart rate is slowed
CLASS IV: CALCIUM CHANNEL BLOCKERS
Reduce calcium entry and depress phase 4 depolarization, which reduces automaticity, slows
conduction velocity, and reduce contractility
DYSRHYTHMIA
An abnormality in the rhythm of the heartbeat
,T WAVE
Repolarization of the ventricles, so this wave is not associated with overt physical activity of the
heart
QRS COMPLEX
Cause by depolarization of the ventricles and corresponds to ventricular contraction
T/F: All antidysrhythmic drugs can worsen existing dysrhythmias and generate new ones.
True.
ACTIVITY 2
NSG124.10.01.02 ANTIDYSRHYTHMIC DRUGS
SODIUM CHANNEL BLOCKER - LIDOCAINE
Used only for ventricular dysrhythmias
DIGOXIN
Supraventricular dysrhythmias by decreasing conduction through the AV Node and by
decreasing automaticity in the D=IN
POTASSIUM CHANNEL BLOCKER - AMIODARONE
Approved only for life-threatening ventricular dysrhythmias and adverse effects related to
ophthalmic and pulmonary toxicities
SODIUM CHANNEL BLOCKER - QUINIDINE
Broad-spectrum agent active against supraventricular and ventricular dysrhythmias
BETA BLOCKER - PROPANOLOL
Treating dysrhythmias caused by excessive sympathetic stimulation of the heart
, CALCIUM CHANNEL BLOCKER - VERAPAMIL
Slow ventricular rate in patients with atrial fibrillation or atrial flutter and terminate SVT caused
by an AV nodal reentrant circuit
ACTIVITY 3
NSG124.10.01.03 NURISNG CARE FOR ANTIDYSRHYTHMIC AGENTS
CASE STUDY
You are the nurse in the cardiac care rehabilitation unit. Mr. Jones is a 68-year-old man who
was recently diagnosed with atrial fibrillation. He has the following questions regarding his
condition:
What is the cause of my dysrhythmia?
ANSWER & RATIONALE
Answer: A dysrhythmia is defined as an abnormality in the rhythm of the heartbeat. In their
mildest forms, dysrhythmias have only modest effects on cardiac output. However, in their most
severe forms, dysrhythmias can so disable the heart that no blood is pumped at all.
Rationale: Dysrhythmias result from alteration of the electrical impulses that regulate cardiac
rhythm, and antidysrhythmic drugs control rhythm by correcting or compensating for these
alterations. Because of their ability to compromise cardiac function, dysrhythmias are associated
with a high degree of morbidity and mortality.
How will my atrial fibrillation be treated?
Answer: Long-term therapy is with a beta blocker (atenolol or metoprolol) or a cardioselective
calcium channel blocker (diltiazem or verapamil), both of which impede conduction through the
AV node. To prevent stroke, most patients are treated with warfarin.
Rationale: Treatment of atrial fibrillation has two goals: improvement of ventricular pumping and
prevention of stroke. Pumping can be improved by either (1) restoring normal sinus rhythm or
(2) slowing ventricular rate. The preferred method is to slow ventricular rate. Warfarin
(Coumadin) is also prescribed.