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175 Cards in this Set

  • Front
  • Back
purposeful destruction of heart muscle cells, usually in an attempt to control a dysrhythmia
a medication that suppresses or prevents a dysrhythmia
antiarrhythmic medication
ability of the cardiac cells to initiate an electrical impulse
electrical current administered in synchrony with the patient’s own QRS complex to stop a dysrhythmia
rate of impulse formation
transmission of electrical impulses from one cell to another
electrical current administered to stop a dysrhythmia, not synchronized with the patient’s QRS complex
process by which cardiac muscle cells change from a more negatively charged to a more positively charged intracellular state
conduction velocity
disorder of the formation or conduction (or both) of the electrical impulse within the heart, altering the heart rate,heart rhythm, or both and potentially causing altered blood flow (also referred to as arrhythmia)
a signal produced by a pace maker when it is interrogated to indicate a near depleted battery
elective replacement indicator (ERI)
a device implanted into the chest to treat dysrhythmias
implantable cardioverter defibrillator (ICD)
in reference to pacemakers, term used to describe the pacemaker withholding an impulse (not firing)
force of myocardial contraction
the part of an electrocardiogram (ECG) that reflects conduction of an electrical impulse through the atrium; atrial depolarization
P wave
a dysrhythmia that has a sudden on set and or termination and is usually of short duration
paroxysmal dysrhythmia
the duration between the beginning of one P wave and the beginning of the next P wave; used to calculate atrial rate and rhythm
PP interval
the part of an ECG that reflects conduction of an electrical impulse from the sinoatrial (SA) node through the atrioventricular (AV) node
PR interval
an agent (eg, a medication) that causes or exacerbates a dysrhythmia
the part of an ECG that reflects conduction of an electrical impulse through the ventricles; ventricular depolarization
QRS complex
the part of an ECG that reflects the time from ventricular depolarization through repolarization
QT interval
process by which cardiac muscle cells return to a more negatively charged intracellular condition, their resting state
the duration between the beginning of one QRS complex and the beginning of the next QRS complex; used to calculate ventricular rate and rhythm
RR interval
the level that the intracardiac electrical activity must exceed in order to be sensed by a pacemaker
electrical activity of the heart initiated by the sinoatrial (SA) node
sinus rhythm
the part of an ECG that reflects the end of the QRS complex to the beginning of the T wave
ST segment
a rhythm that originates in the conduction system above the ventricles
supraventricular tachycardia (SVT)
the part of an ECG that reflects repolarization of the ventricles
T wave
the part of an ECG that reflects the time between the end of the T wave and the beginning of the next P wave; used to identify the isoelectric line
TP interval
in reference to pacemakers, term used to describe the release of an impulse in response to some stimulus
the part of an ECG that may reflect Purkinje fiber repolarization; usually it is not seen unless a patient’s serum potassium level is low
U wave
a rhythm that originates in the ventricles
ventricular tachycardia (VT)
The _____________node is a section of nodal tissue that is located in the upper wall of the right atrium. The SA node is also referred to as the pacemaker of the heart.
Sinoatrial (SA)
True or false?

The electrical impulse occurs at a rate of 60 to 100 beats per min.
The electrical impulse quickly travels from the sinus node through the atria to the ___________.
Atrioventricular node (AV)
True or false?

The structure of the AV node slows the electrical impulse giving the muscle cells of the atria time to contract and feel the ventricles with blood. This part of the atrial contraction is frequently referred to as the atrial kick.
After the AV node where does the electrical impulse go?
The electrical impulse then travels very quickly through the bundle of his to the right and left bundle branches and the purkinje fiber located in the ventricular muscle.
The electrical stimulation of the muscle cells of the ventricles in turn causes the mechanical contraction of the ventricles.What is this?
The cells re-polarize and the ventricles relax. What is this?
True or false?

The ventricles of heart have two states: systole (contraction) and diastole (relaxation). During diastole blood fills the ventricles and during systole the blood is pushed out of the heart into the arteries. The auricles contract anti-phase to the ventricles and chiefly serve to optimally fill the ventricles with blood.
The electrical stimulation is called ___________ and the mechanical contraction is called systole.
Electrical relaxation is called _________ and mechanical relaxation is called diastole.
Cardiac conduction video:
What is an electrocardiogram?
An electrocardiogram (EKG or ECG) is a test that checks for problems with the electrical activity of your heart.
Why would you have a ECG?
1. Check the heart's electrical activity.

2. Find the cause of unexplained chest pain, which could be caused by a heart attack, inflammation of the sac surrounding the heart (pericarditis), or angina.

3. Find the cause of symptoms of heart disease, such as shortness of breath, dizziness, fainting, or rapid, irregular heartbeats (palpitations).

4. Find out if the walls of the heart chambers are too thick (hypertrophied).

5. Check how well medicines are working and whether they are causing side effects that affect the heart.

6. Check how well mechanical devices that are implanted in the heart, such as pacemakers, are working to control a normal heartbeat.

7. Check the health of the heart when other diseases or conditions are present, such as high blood pressure, high cholesterol, cigarette smoking, diabetes, or a family history of early heart disease.
____ wave: the sequential activation (depolarization) of the right and left atria. Book states: The electrical impulse starting in the sinus node and spreading through out the atria.
P wave

right and left ventricular depolarization (normally the ventricles are activated simultaneously)
QRS complex

This is normally 2.5mm or less and height and 0.11 second or less in duration.
P wave
True or false?

To prevent interference form the electrical activity of skeletal muscle the limb electrodes are usually placed on areas that are not bony and do have have significant movement.
Explain how to place Lead V1 for a normal ECG.
On the right side of the sternum locate the 4 intercostal space and place your lead.
Explain how to place Lead V2 for a normal ECG.
Place in the 4th intercostal space on the left side of the sternum.
Explain how to place a lead V3 for a normal ECG.
It is place diagonally between V2 and V4.
Explain how to place a lead for V4 for a normal ECG.
It is placed in the 5th intercostal space in the mid clavicle line.
Explain how to place a lead for V5for a normal ECG.
It is placed in the 5th intercostal space in the anterior axillary line.
Explain how to place a lead for V6 for a normal ECG.
It is placed in the 5th intercostal space in the mid-axillary line.
True or false?

A standard 12 lead ECG reflects the electrical activity primarily in the left ventricle.
When ECG waveform moves toward the top of the graft paper its is known as a _________ deflection.
When the ECG waveform moves toward the bottom of the graft paper it is known as a __________ deflection.
In the QRS complex the ___ is the first negative deflection after the P wave and is less than 0.04 seconds in duration and less than 25% of the R wave amplitude.
The _ wave is the first positive deflection after the P wave and the S wave is the first negative deflection after this wave.
R wave
When the QRS complex is less than 5mm tall it is documented as?
qrs (small letters)
The QRS complex is normally less than _____ seconds in duration.
The ____ wave represents ventricular repolarization it is also the resting state.
The __ wave is thought to represent re-polarization of the Purkinje fibers. However, it is also seen in patients with hyper tension, hypokalemia or heart disease.
U wave
The ____ segment represents early ventricular re polarization last form the end of the QRS complex to the beginning of the T wave.
The _______ interval is measured from the beginning of the P wave to the beginning of the QRS completes and reprisens the time needed for sinus node stimulation.
The ____ represents early ventricular repolarization lasts from the end of the QRS complex to the beginning of the T wave.
ST segment
Why is it important to analyze the ST segment?
To identify whether it is above or below the isoelectric line which may be among other signs and symptoms and a sign of cardiac ischemia.
The _________ represents the total time for ventricular depolarization and re-polarization, it is measured from the beginning of the QRS complex to the end of the T wave.
QT interval
True or false

The QT interval lasts 0.32 to .40 seconds in duration if the heart rate is 65 to 95 beats per min.
If the QT interval becomes to long the patient is at risk for a lethal ventricular dysrhythmia known as?
Torsades de Points
The _______ interval is measured from the end of the T wave to the beginning of the next P wave.
TP interval
True or false

When no electrical activity is present this is known as the isoelectical line.
The ________ interval is measure from the beginning of one P wave to the next is is used to determine Atrial rate and rhythm.
PP interval
True or false?

A 1 min strip contains 300 large boxes an 1500 small boxes.
True or false?

To count the Ventricular rate count all the RR intervals within a 6 secs and them multiply by 10.
To count atrial rate count all the PP intervals within a 6 secs and them multiply by 10.
For this rate:
Atrial rate is between 60 and 100 bpm.

Ventricular and atrial rhythm is regular.

P wave is present and always in front of the QRS

PR interfal is between .12 and .2 seconds.

QRS ratio is 1:1
Normal Sinus Rhythm

_________ occurs when the sinus node creates an impulse at a slower than normal rate.
Sinus Bradycardia
What can cause sinus bradycardia?
Vagal stimulation

Medications(calcium channel blockers, amiodarone, beta blockers

Idiopathic sinus node dysfunction

Increased intracranial pressure (ICP)

Myocardial infraction (MI)



hydrogen ion (acidosis)




tension pneumothorax

What are the characteristics of Sinus bradycardia?
Ventricular and atrial rate is lower than 60bpm

QRS is normal

PR interval is consistand between .12 and .2 seconds

Rhythm is consistent.
True or false?

All characteristics of sinus bradycardia are the same as those of normal sinus rhythm except for the rate.
______ occurs when the sinus node creates an impulse at a faster then normal rate.
Sinus Tachycardia
What are the characteristics of Tachycardia.
Ventricular and atrial rate is faster than 100 bpm.

QRS is normal

PR interval is consistand between .12 and .2 seconds

Rhythm is consistent.
True or false?

As the heart rate increases the diastolic filling time decreases possibly resulting in reduced cardiac output and subsequent symptoms of syncope and low blood pressure. If the rapid rate persists and the heart can not compensate for the decreased ventricular filling the patient may develop acute pulmonary edema.
___________ occurs when the sinus node creates an impulse at an irregular rhythm the rate is usually increased with inspiration and decreases with expiration.
Sinus Arrhythmia
What are the characteristics of sinus arrhythmia?
Ventricular and atrial rate is 60 to 100 bpm

Ventricular and atrial rhythm is irregular.

QRS shape and duration: usually normal but may be abnormal.

P wave: normal and consistent

PR interval: Consistent interval between .12 and 0.20 seconds.

P: QRS ratio 1:1
___________ is a single ECG complex that occurs when an electrical impulse states in the atrium before the next normal impulse of the sinus node.
Premature Atrial Complex (PAC)

What are the causes of PAC?



stretched atrial myocardium



hypermetabolic states

atrial ischemia


The heart is under the control of the autonomic nervous system. Stimulation of the parasympathetic system results in all of the following except:

a. a slowed heart rate

b. lowered blood pressure

c. Reduction in the force of contraction.

d. Potitive inotropy.
The total time for ventricular depolarization and repolarization is represented on an ECG reading as the?

a. QRS complex

b. QT interval

c. ST segment

d. TP interval
Ventricular rate and rhythm can be determined by examining what interval on an ECG strip?

a. PP interval

b. QT interval

c. RR interval.

d. TP interval
The PR interval on an ECG strip that reflects normal sinus rhythm would be between?

a. 0.05 and 0.10 seconds

b. 0.12 and 0.20 seconds

c. 0.15 and .030 seconds

d. 0.25 and 0.40 seconds
Characteristics of sinus bradycardia include all of the following except?

a. A P wave preceds every QRS complex

b. Every QRS complex is normal

c. The rate is 40 to 60bpm

d. The rhythm is altered.
Ventricular rate and rhythm can be determined by examining what interval on an ECG strip?

a. PP interval

b. QT interval

c. RR interval

d. TP interval
The PR interval on an ECG strip that reflects normal sinus rhythm would be between?

a. 0.05 and 0.10 seconds

b. 0.12 and 0.20 seconds

c. 0.15 and 0.30 seconds
A dysrhythmia common in normal hearts and described by patients as "my heart skipped a beat" is?

a. Premature atrial complex (PAC)

b. atrial flutter

c. sinus tachycardia

d. ventricular fibrillation
A sawtooth P wave is seen on an ECG strip with?

a. Sinus bradycardia

b. atrial flutter

c. atrioventricular nodal reentry

d. premature junctional complex.
Atrial fibrillation is associated with a heart rate up to?

a. 300 bpm

b. 400 bpm

c. 500 bpm

d. 600 bpm
Atrioventricular (AV) nodal reentry tachycardia is characterized by an atrial rate?

a. Of 100 bpm

b. betwen 100 and 150 bpm

c. between 150 and 250 bpm

d. more than 250 bpm
Ventricula rbigeminy refers to a conduction defect in which?

a. Conduction is primaryly from the AV block.

b. every other beat is premature

c. rhythm is regular but fast.

d. the rate is between 150 and 250 bpm
With ventricular tachycardia?

a. conduction originates in the ventricle.

b. electrical defibrillation is used immediately.

c. the P wave usually is normal

d. all of the above.
Ventricular fibrillation is associated with an absence of?

a. heartbeat

b. palpable pulse

c. respirations

d. all of the above.
First degree AV block is characterized by

a. averiable heart rate usually fewer than 60 bpm

b. an irregular rhythm

c. delayed conduction producing a prolonged PR interval

d. P waves hidden within the QRS complex.
A conduction abnormality whereby no atrial impulse travels through the AV node is known as?

a. First degree AV block.

b. second degree AV block.

c. second degree AV block type 2

d. third degree AV block.
Cardioversion is used to terminate dysrhymias. With cardioversion the?

a. amount of votage used should exceed 400 W-s

b. electrical impulse can be discharged during the T wave.

c. defibrillator should be set to deliver a shock

d. above statement are all true.
When assessing vital signs in a patient with a permanent pacemaker the nurse needs to know the?
Pacer rate.
Candidates for impantable cardioverter defibrillation (ICD) are patients at high risk who have?

a. Experienced syncope secondary to ventricular tachyardia

b. survived sudden cardiac death.

c. sustained ventricular tachycardia.

d. Experienced one or more of the above.
The nurse needs to teach the patient with an automatic ICD that he or she must?

a. avoid magnetic fields such as a metal detection booths.

b. call for emergency assistance if he or she feels dizzy.

c. Record events that trigger a shock sensation.

d. be compliant with all of the above.
Name the four sites of origin for impulses that are used to name dysrhythmias.
1. Atria

2. Atrioventricular node or junction.

3. Sinus node.

4. Ventricles
Describe the normal electrical conduction through the heart.
Electrical conduction through the heart begins in the SA node travels across the atria to the AV node and then travels down the right and left bundle branches and Purkinje fibers to the ventricular muscle.
Name some of the causes for sinus tachycardia.
1. Fever

2. hypovolemia

3. anemia

4. exercise.

5. pain

6. congestive heart failure.

7. anxiety

8. Sympathomimetic or parasynmpatholytic drugs.
Sinus tachycardia occurs when the ventricular and atrial rate are greater than____ bpm.
List a rate and rhythm characteristic that is necessary to diagnosis ventricular tachycardia.
Ventricular tachycardia occurs when there is more than three PVCs in a row and the rate exceeds 100 bpm.
List three potential collaborative problems that a nurse would choose for a patient with dysrhythmias.
1. a thromboembolic event

2. Heart failure.

3. cardiac arrest.
Name one major difference between cardioversion and defibrillation.
The difference is in the timing of the electrical current. With cardioversion the current is synchronized with the patients electrical events; with defibrillation the current is synchronized and immediate.
For defibrillation, describe the placement of the electrode paddles on a patients chest.
The standard procedure is to place one paddle to the right of the upper sternum below the right clavicle and the other paddle just to the left of the cardiac apex.
Describe the difference between on demand and fixed or asynchronous pacemakers.
An on demand pacemaker is set for a specific rate and stimulates the heart when normal ventricular depolarization does not occur; the fixed rate pacemaker stimulates the ventricle at a preset constant rate independently of the patients rhythm.
Describe the Maze Procedure used in cardiac conduction surgery.
Small incisions are made through the atria so that scar tissue forms and prevents reentry conduction of the electrical impulse.
A term used to describe an irregular or erratic heart rhythm
The ability of the cardiac muscle to initiate an electircal impulse.
The ability of the cardica muscle to transmit electrical impulses
A term used to describe the electrical stimulation of the heart.
Stage of conduction in which the ventricles relax
Treatment of dysrhythmias by destroying causative cells
Mr. Woo'spacemaker is set to 72bpm. His heart rate is 76bpm. Is this expected? If so explain why?
Yes. Heart rate can vary as much as 5bpm faster or slower than the present rate.
Nursing care for a pacemaker includes incision site assement for three potential complications.
Bleeding, hematoma formation, and infection.
List for addtional complicaitons that a patient with a pacemaker may experience.
Hemothorax, ventricular ectopy and tachycardia, dislocation of the lead and phrenic nerve, diaphragmatic or skeletal muscle stimulation.
The most common initial postoperative pacemaker complication is?
dislodgement of the pacing electrode
List six thing abourt the pacemaker that must be noted in the patients chart.
1. pacemaker model
2. date and time of insertion
3. stimulation threshold
4. pacer rate
5. incision appearance
6. patient tolerance
True or false?

If PAC's are infrequent no treatment is necessary if they are frequent (more than 6 per min.) this may herald a worsening of disease state or the onset of more serious dysrhythmias such as atrial fibrillation. Treatment is directed toward the cause.
__________ occurs because of conduction defect in the atrium and causes a rapid regualar atrial rate usually between 250 to 400 time per min. Because the atrial rate is faster than the AV node can not conduct.
Atrial Flutter.
Atrial flutter often occurs in patients with?
COPD, Valvular disease, Thyrotoxicosis as well as pts following open heart surgery.
What are the characteristics of atrial flutter?
Ventrical and Atrial rate : Atrial rate ranges between 250 and 400; Ventricular rate is usually between 75 and 150

Ventricular and atrial rhythm: The atrial rhythm is regular; the ventricular rhythm is regular

ORS shape and duration: Usually normal but may be abnormal or may be absent.

P wave: Saw toothed shape; these waves are refereed to as f waves.

PR interval: Multiple F waves make it difficult to determine the PR interval.

P: QRS ratio: 2:1; 3:1; 4;1
What does a Atrial flutter look like?
True or false?

Atrial flutter can cause serious signs and symptoms such as chest pain, SOB, and low BP.
What is used to correct atrial flutter if it does not correct its self?
__________ is an uncoordinated atrial electrical activation that causes a rapid disorganized and uncoordinated twitching of atrial musculature.
Atrial Fibrillation.



True or false?

Atrial fibrillation usually occurs in people of advanced age with structural heart disease such as valvular heart disease such as mitral or tricuspid, inflammatory such as pericarditis, myocarditis, amyloidosis, coronary artery disease hypertension, congenial disorder especially atrial septal defect and heart failure.
___________ atrial fibrillation occurs with sub arachnoid hemorrhage and non hemorrhagic stroke is caused by in creased vagal or sympathetic stimulation.
What are the characteristics of atrial fibrillation?
Ventricular and atrial rate: Atrial rate is 300 to 600; Ventricular rate is usually 120 to 200 in untreated atrial fibrillation.

Ventricular and atrial rhythm: Highly irregular

QRS shap and duration: Usually normal, but may be abnormal.

P wave: None present or irregular.

PR interval: Cannot be measured

P:QRSratio: Many:1
True or false?

The clinical evluation of atrial fibrillation should in clude a history and physical examination, 12 lead EGC, Ecocardiogram, and blood test to assess thyroid renal and hepatic function.
True or false?

In many patients A-fib converts to sinus rhythm within 24hrs without treatment.
True or false?

Electrical cardioverion is indicated for patients with atrial fibrillation that is hemodynamically unstable unless they have digitalis toxicity or hypokalemia. Because fo the high risk of atrial thrombi cardioversion of atrial fibrillation that has lasted longer than 48hr should be avoided unless the patient has received warfarin for at least 3 to 4 weeks.
What is torsade de points?
Ventricular Tachycardia
If cardiversion is necessary to due on a patient before they have had 3 to 4 weeks of warfarin what do we do?
Make sure there is not a thrombus and administer heparin prior to cardioversion.
What is this?

An accessory pathway is congenital tissue between the atria, his bundle, AV node, Purkinje fiber, or ventricular myocardium. This anomaly is known as what kind of syndrome?
Wolff Parkinson White or WPW syndrome.
True or false?

Patients with atrial fibrillation who have a coronary artery stent implanted should receive clopidogrel (Plavix), an anti-platelet agent plus warfarin for 1 to 12 months following the procedure.
__________ or _________ rhythms occurs when the AV node instead of the sinus node becomes the pacemaker of the heart.
Junctional or Idionodal
True or false?

Junctional tachycardia is caused by enhanced automaticity in the junctional area resulting in a rhythm similar to a junctional rhythm except at a rate of 70 to 120. It may be indicate a serious underlying condition such as digitialis toxicity, myocardial ischemia, hypokalemia, or COPD.
______________ is a disorder of the heart in which the ventricles of the heart contract prematurely due to an accessory pathway known as the bundle of Kent. This accessory pathway is an abnormal electrical communication from the atria to the ventricles. WPW is a type of atrioventricular reentrant tachycardia.
Wolff–Parkinson–White syndrome (WPW)
True or false?

WPW syndrome is commonly diagnosed on the basis of the surface ECG in an asymptomatic individual. In this case it is manifested as a delta wave, which is a slurred upstroke in the QRS complex that is associated with a short PR interval. The short PR interval and slurring of the QRS complex is actually the impulse making it through to the ventricles prematurely (across the accessory pathway) without the usual delay experienced in the AV node.
True or false?

Patients whiht atrial bibrillation who have a coronary artery stent implanted should receive clopidogrel (plavix) an antiplatelet agent plus warfarin for 1 to 12 months following the procedure
__________ or idionodal rhythem occurs when the AV node, instead of the SA node becomes the pacemaker of the heart.
_________ is a common dysrhythmia that occurs when an impulse is conducted to an area in the AV node that causes the impluse to be rerouted back into the same area over and over again at a very fast rate.
Atrioventricular Nodal Reentry Tachycardia
If P waves cannot be identified the rhythm may be called Supraventricular tachycardia (SVT) or paroxysmal supraventricular tachyardia. How do you correct this?
Have Pt try vagal maneuvers to slow heart rate down such as baring down. If that does not work Adenosin may be used to convert the rhythm or at least slow the conduction.
What is a PVC?
It is a premature ventrical complex and stares in the ventricle and is conducted through the ventricles before the next normal beat.

What is Ventricular Tachycardia?
VT is defined as a three or more PVCs in a row occuring at a rate exceeding 100 bpm.

________ is the treatment of choice for monophasic VT in a symptomatic patient.
___________ is the treatment of choice for pulseless VT.
___________ is the most common dysrhthmia in patients with cardiac arrest.
Ventricular Fibrillation (widow maker)

______________ is always characterized by the absence of an audible heart beat, no pulse, and no respirations.
Ventricular fibrillation
__________ is commonly called flatline.
Ventricular asystole.
__________ also called a ventricular escape rhythm occurs when the impulse starts in the conduction system below the AV node or when the impulse is created by canno be conducted trough the AV node. Purkinje fibers automatically discharge at a rate of 20 to 40bpm.
Idoventricular rhythm
What causes Asystole?
Check your patent first... Dont freak out like I did and go get Sarah and Darrel while the Pt is setting up in bed drinking coffee... Possible causes are

1. Leads not conected correctly
2. Hypoxia
3. acidosis
4. severe electrolyte imblance
5. drug overdose
6. hypovolemia
7. cardiac tamonade
8. tension pneumothorax
9. coronary or pulmonary thrombosis.
10. trama
11. hypothermia.
What do we do in Asystole?
1. Start CPR, intubation and establish an IV access.

2. After 2 mins or 5 cycles of CPR a bolus IV of epinephrine is administerd and repeated at 3 to 5 min intervals.

3. One dose of vasopressin may be administered for the first or second dose of epenephrine and a bolus IV of atropine may administered as soon as possible after the rhythm check.
What the heck is a 1st degree AV block?
It is a block that occurs when all the atrial impulses are conducted through the AV node into the ventricles at a rate slower than normal.
What is a second degree AV block Type I aka Wenckebach?
Occurs when there is a repeating pattern in which all but one of a series of atrial impulses are conducted through the AV node into the ventricles.
What is a second degree AV block Type II?
Second degree AV block type II occurs when only some of the atrial impulses conducted through the AV node into the ventricles.
What is a third degree AV block?
Occurs when on atrial impulse is conducted through the AV node into the ventricles. In third degree AV block two impulses stimulate the heart and one stimulates the ventricles.
What is a cardioversion?
It is a timed electrical current to terminate a tachydyrhythmia.
True or false?

If a cardioversion is elective and the dysrhythmia has lasted for longer than 48hrs anticoagulation for a few weekds before the cardioversion may be indicated. Digoxin is ususally withheld for 48hrs before cardioversion to ensure that resumption of sinus rhythm with in normal conduction.
True or false?

Defibrillation is used in emergency situations as teh treatmetn of choice for ventricular fibrillation and pulse-less VT the most common cause of abrupt loss of cardiac function and sudden cardiac death.
True or false?

Epinephrine or vastopressin is administered after defibrillation to make it easier to convert the dysrhythmia to a normal rhythm with the next defibrillation. Antiarrhythmic medicatoins such as amiodarone, lidocane, or magnesium are administered if ventricular dysrhythmia persists.
A _________ is an eletronic device that provides electical stimuli to the heart muscle.