Cardiac Arrhythmias.

Question 1

(1) ___________ are abnormalities in cardiac rhythm and/or conduction.

(2) Often differentiated by rate (tachycardia vs bradycardic) and QRS duration (wide vs narrow).

(3) Dangerous to the extent that they reduce cardiac output, thereby decreasing brain and myocardial perfusion.

Answer 1

Cardiac Arrhythmias

Question 2

(1) Can be lethal (sudden cardiac death)
(2) Symptoms can range from asymptomatic to palpitations to dizziness to pre- syncope to syncope.

Answer 2

Physical Findings: Cardiac Arrhythmias.

Question 3

Detected because patients present with symptoms or detected during a routine screening

physical or age related screening

Answer 3

Diagnosis: Cardiac Arrhythmias.

Question 4

ECG is the gold standard for monitoring and diagnosing ___________.

Answer 4

Cardiac Arrhythmias Diagnosis

Question 5

(1) Depending on the dysrhythmia and patient presentation, ABCs, IV, Oxygen, Monitor.

(2) Varies by arrhythmia and symptoms. Treatment can include antiarrhythmic drugs and more techniques such as cardioversion or
transcutaneous pacing.

(3) Definitive treatment may be required via a catheter ablation by a Cardiologist.

Answer 5

Treatment: Cardiac Arrhythmias

Question 6

Decreased cardiac perfusion leading to AMI, syncope, cardiac arrest, and/or death.

Answer 6

Complications: Cardiac Arrhythmias

Question 7

Disposition: Cardiac Arrhythmias

Answer 7

Stabilize if able and transfer to a higher level of care/MEDEVAC.

Question 8

What Rhythm?
Beat originates in the SA node and follows the appropriate conduction pathways. The intrinsic rate is 60-100 beats/min and the rhythm is regular. Every beat has a P wave, and every P wave is followed by a
QRS complex.

ECG
1) PR interval remains constant.
2) R-R interval is regular and constant.
3) P-P interval is constant

Physical Findings
1) Disappears with breath holding or with an increased heart rate (from activity or exercise).
2) No clinical significance
3) Common in both the young and elderly

Answer 8

Normal Sinus Rhythm

Question 9

What Rhythm?
Heart rate slower than 60 beats/min due to increased vagal tone on normal pacemaker, organic disease of the SA node, or due to medications.

ECG
1) Heart rate < 60 beats/min
2) Normal and consistent P wave morphology followed by QRS complex.
3) Normal PR interval

Physical Findings
1. < 45 beats/min may cause weakness, chest
pain, lightheadedness, N/V, confusion, or syncope. The rate usually increases with exercise or administration of Atropine.

2. In healthy individuals in excellent physical condition sinus bradycardia to rates of 50 beats/min or lower is a normal finding.

Answer 9

Sinus Bradycardia

Question 10

1) Perform rapid and primary assessments.
2) Determine if heart rate is less than 50 bpm.
3) Determine if the patient is stable or unstable.

a) Unstable is defined as:
(1 Changes in mental status.
(2 Ischemic chest discomfort.
(3 Hypotension
(4 Signs of shock.
(5 Acute heart failure.

4) If the patient is stable then monitor the patient, obtain vitals, obtain 12 lead if able, attempt to identify and treat underlying causes.

Answer 10

General Treatment- Bradyarrhythmia (ALS)

Question 11

1st give Atropine 0.5 mg IV push and repeat q 3-5 minutes for a maximum of 3 mg

(1 Atropine works by inhibiting all vagal input into the SA node

(2 Atropine does not work for any patient that has undergone a heart transplant

**(3 Side Effects: Tachycardia, urinary retention, blurred vision, photophobia, constipation, MYDRIASIS (dilated pupils).

b) If Atropine ineffective prepare for transcutaneous pacing OR
c) Consider Dopamine IV infusion at 2-10 mcg/kg/min OR
d) Epinephrine IV infusion 2-10 mcg/min (use 1:10,000 epinephrine
mixture).

Answer 11

Treatment- Bradyarrhythmia (ALS) UNSTABLE

Question 12

1) Ventricular ectopic rhythms are more
likely to occur with slow sinus rates.
2) AMI due to slow heart rate and inadequate cardiac output.
3) Cerebral or renal ischemia due to inadequate cardiac output.

Answer 12

Complications: Bradyarrhythmia (ALS) UNSTABLE

Question 13

What Rythem?
1) Heart rate faster than 100 beats/min caused by rapid impulse formation from the SA node.
2) Occurs with fever, exercise, emotion, pain, anemia, heart failure, pregnancy, early shock, thyrotoxicosis, alcohol withdrawal or in response to many drugs.
3) The rate infrequently exceeds 150 beats/min.

ECG
1) HR > 100 beats/min
2) P wave is followed by a QRS complex and each QRS has a P wave preceding it.
3) QRS complex is normal duration (< .12 seconds).

Answer 13

Sinus Tachycardia

Question 14

1) ABCs, monitor, IV, Oxygen to maintain saturation > 94%.
2) Assess appropriateness of clinical condition.
3) Usually Sinus Tachycardia has an identifiable etiology. Once identified then treat accordingly (dehydration, fever, stimulants, infection, pain, etc.)
4) If no identifiable etiology determined and patient is unstable ACLS protocol.

Answer 14

General Treatment: Sinus Tachycardia

Question 15

(1 Changes in mental status
(2 Ischemic chest discomfort
(3 Hypotension
(4 Signs of shock
(5 Acute heart failure

Answer 15

Unstable Sinus Tachycardia and Supraventricular Tachycardia (PSVT)

Question 16

1) Paroxysmal = comes and goes
2) Supraventricular = originating above the ventricles
3) Tachycardia = HR > 100 beats/min
4) Most common paroxysmal tachycardia and often occurs in patients without structural heart disease.
5) The most common mechanism is reentry (Atrioventricular nodal reentry tachycardia (AVNRT))

ECG
1) HR 150-240 (commonly HR is 160-220)
2) Regular R-R interval
3) Narrow QRS complex
4) P wave often buried in the narrow QRS complex

Answer 16

Paroxysmal Supraventricular Tachycardia (PSVT)

Question 17

1) May be asymptomatic
2) Frequently associated with palpitations, mild chest pain or shortness of breath.
3) Episodes usually begin and end abruptly
4) May cause syncope
5) May cause AMI

Answer 17

Physical Findings: Paroxysmal Supraventricular Tachycardia (PSVT)

Question 18

1) In the absence of structural heart disease serious effects are rare and most attacks break spontaneously.
2) ABCs, IV, Vitals, Monitor, Oxygen if saturation < 94%
3) Determine if the patient is stable or unstable

Unstable is defined as:
(1 Changes in mental status
(2 Ischemic chest discomfort
(3 Hypotension
(4 Signs of shock
(5 Acute heart failure

Cardioversion

Mechanical Measure

Drug TherapyDrug Therapy

Answer 18

Treatment: Paroxysmal Supraventricular Tachycardia (PSVT)

Question 19

a) Used to stimulate the Vagus nerve and increase Vagal tone.
b) Valsalva
c) Breath hold
d) Dunk face in bowl of ICE cold water.
e) Carotid sinus massage - will interrupt up to 50% of PSVT (firm but gentle pressure over the right carotid sinus for 10-20 seconds, if unsuccessful then attempt over the left carotid sinus).
(1 Never put pressure on both Carotid sinuses at the same time.

Answer 19

Treatment: Mechanical Measures should be attempted if patient is stable: Supraventricular Tachycardia

Question 20

1. Adenosine - use first line if available
   Antiarrhythmic
   - 6 mg IV push very quickly followed by saline flush quickly repeat 12 mg IV push quickly if 6 mg dose did not work

Beta Blockers - second line
2. Metoprolol 5 mg IV repeat dose every 5 minutes up to 15 mg max.
- Metoprolol 50mg PO BID

Calcium Channel Blockers – second line
3. Diltiazem: 0.25 mg/kg IV over 2 minutes

4. Synchronized Cardioversion - patient is hemodynamically unstable, synchronized electrical
   cardioversion is almost universally successful at 50-150 J

Answer 20

Treatment Drug Therapy: Supraventricular Tachycardia

Question 21

1) Myocardial dysfunction/ischemia
2) CHF
3) Syncope

Answer 21

Complications: Supraventricular Tachycardia

Question 22

1) It is an accessory electrical pathway or bypass tract between the atrium and the ventricle bypassing the AV node and can predispose to reentrant arrhythmias.
2) Associated with PSVT rhythm.

EKG
1) Short PR interval ( < 0.12 seconds).
2) Wide, slurred QRS complex called a delta wave.

Answer 22

Wolf Parkinson White Syndrome (WPW)

Question 23

What rythem is UNSTABLE the perform immediate synchronized cardioversion with 50-150 J.

Stable and in PSVT you can attempt vagal maneuvers just like in PSVT treatment.

Answer 23

Treatment: Wolf Parkinson White Syndrome (WPW)

Question 24

a) Adenosine - same dose as PSVT
b) Metoprolol - same as a PSVT

Answer 24

Medications: Wolf Parkinson White Syndrome (WPW)

Question 25

Ultimately need a referral to a cardiologist for catheter directed radiofrequency ablation.

Answer 25

Wolf Parkinson White Syndrome (WPW) referral

Question 26

1) Most common, chronic arrhythmia, and prevalence increases with age.
2) Multiple areas of atrial myocardium continuously discharging causing the atrium to fibrillate rather than contract in an organized manner.
3) R-R pattern is irregularly irregular.

Answer 26

Atrial Fibrillation

Question 27

A-fib predisposes patients to

Answer 27

thromboembolic events.

Question 28

1) R-R interval is irregularly irregular
2) Atrial rate ~ 400 beats/min and presents as fibrillation waves (wavy baseline).
3) Ventricular rate will depend upon how many of the atrial beats get conducted from the AV node which can range from bradycardia to tachycardia (with rates as high as 170-180

Answer 28

EKG Atrial Fibrillation

Question 29

1) Up to 2/3 of patients experiencing their 1st episode of A-fib will spontaneously revert to sinus rhythm within 24 hours.
2) Goal of treatment should focus on ventricular rate control, conversion of hemodynamically unstable AF to Sinus Rhythm or both.
3) Patients with AF > 48 hours are at risk for cardioembolic events and should not be cardioverted until anti-coagulated for a minimum of 3 weeks prior to attempting elective cardioversion.
4) ABCs, IV, Monitor, Vitals, Oxygen if saturation < 94%
5) Assess for signs of the patient being UNSTABLE, and if so at any point perform synchronized Cardioversion at 100-200 J (even if the patient has been in AF for longer than 48 hours and not been anticoagulated).

Answer 29

Treatment: Atrial Fibrillation

Question 30

Metoprolol 5 mg IV q 5 minutes to a total of 15mg and then start 50 mg PO BID.

Diltiazem: 0.25 mg/kg IV over 2 minutes

Enoxaoarin (Lovenox)
(1 Dose: 1mg/kg SC q12 hours

Answer 30

Medications: Atrial Fibrillation

Question 31

1) Embolic event leading to ischemic stroke, or ischemic extremities.
2) Rapid ventricular rate leading to myocardial dysfunction or ischemia.

Answer 31

Complications: Atrial Fibrillation

Question 32

1) Usually associated with Pulmonary disease.
2) Originates from a localized area in the atria.
3) Predisposes patients to thromboembolic events.
4) Different disorders that can cause A-Flutter

EKG
1) Saw tooth flutter waves between QRS complexes.
2) Atrial rate between 250-350 beats/min.
3) AV block 2:1, 3:1, 4:1

Answer 32

Atrial Flutter

Question 33

1) Goal of treatment should focus on ventricular rate control, conversion of hemodynamically unstable AF to Sinus Rhythm or both.

2) Ventricular rate control is accomplished using the same agents as in atrial fibrillation, but is more difficult to control.
a) Metoprolol
b) Diltiazen

3) If UNSTABLE at all then proceed directly to synchronized cardioversion with 100-200 J.

Answer 33

Treatment: Atrial Flutter

Question 34

1) Embolic event in chronic aflutter is the same as chronic atrial fibrillation.
2) Myocardial ischemia
3) Dizziness or syncope
4) Heart failure

Answer 34

Complications: Atrial Flutter

Question 35

a) Non-Sustained V-tach: 3 or more consecutive ventricular premature beats lasting < 30 seconds and terminating spontaneously.
b) Sustained V-tach
c) Pulseless (will talk about in cardiac arrest Advanced Life Support section).

Most common cause of ________ is AMI, ischemic heart disease, or electrolyte abnormalities (hypokalemia, hypomagnesemia).

Life threatening because it may lead to pulseless V-tach, V-fib, and death

EKG
1) Wide QRS complex (longer than 0.12 seconds).
2) Absence of p waves
3) Tachycardia, usually HR 160-240 beats/min.
4) Moderately regular R-R interval.

Answer 35

Ventricular Tachycardia

Question 36

1) IV, Monitor to identify rhythm, Vitals, Oxygen if saturation < 94%.
2) IF Pulseless V-Tach then initiate ACLS Protocol.
3) If they have a pulse then assess if unstable or not.
4) If stable then MEDADVICE and possibly treat with
Antiarrhythmic medication (see below).
5) If unstable then immediately perform synchronized
cardioversion 100-200 J.

MEDS
a) Lidocaine 0.5-0.75 mg/kg IV repeat every 5-10 minutes to a max dose of 3 mg/kg total.

b) Amiodarone 150 mg IV over 10 minutes followed by 1 mg/min x 6 hours then 0.5 mg/min for the next 18 hours.

c) Magnesium
(1 Give 2 grams IV if you suspect low magnesium

Answer 36

Treatment: Ventricular Tachycardia

Question 37

Progression to pulseless V-tach, V-fib, or death.

Answer 37

Complications: Ventricular Tachycardia

Question 37

1) If the HR is between 100-150 and stable then:
a) Monitor the patient (vitals, oxygen level, cardiac rhythm).
b) Obtain 12 lead EKG if possible.
c) Identify and treat underlying cause (dehydration, blood loss, fever, infection, anxiety, etc.)

2) If the HR is > 150 the determine is the patient stable or UNSTABLE.
a) If UNSTABLE at any time (change in mental status, ischemic chest discomfort, hypotension, signs of shock, acute heart failure) then perform IMMEDIATE cardioversion start at 100 J and increase voltage
if needed up to 200 J.

b) If stable with HR > 150 then you need to determine if they have a NARROW QRS complex (<0.12 sec) or WIDE QRS complex (greater than or equal to 0.12 sec).
(a If vagal maneuvers ineffective then attempt Adenosine 6 mg
(b If Adenosine ineffective or the tachyarrhythmia recurs, then consider MEDADVICE and Beta Blocker or CCB.

(2 If Wide complex and stable, then.
(a If regular and monomorphic (same looking QRS complex), consider adenosine.
(b Consider antiarrhythmic infusion of Procainamide,
Amiodarone, or Sotalol if available.
(c Consider expert consultation (Cardiologist if available).

Answer 37

Tachyarrhythmia per Advanced Life Support Protocol

Question 37

1) _____ impulses originating from the ventricles.
2) are very common, even in patients without heart disease, but occur most in patients with ischemic disease.
3) Other common causes include hypoxemia, CHF, Digoxin toxicity, caffeine use, hyperthyroidism, and electrolyte abnormalities.
4) Patients with underlying structural heart disease with _______s are at increased risk of development of Ventricular Fibrillation, especially following AMI.

EKG
1) Wide QRS complex without a preceding P-wave.
2) Occurs before then next predicted QRS complex is set to occur.

Symptoms
1) Usually asymptomatic
2) Palpitations
3) Dizziness

Answer 37

Premature Ventricular Contraction (PVC)

Question 38

1) If the patient is asymptomatic and has no organic/structural heart disease; then no treatment is necessary.
2) In the case of frequent PVCs in a patient with underlying structural heart disease then start Metoprolol 50 mg PO BID.

Answer 38

Treatment: Premature Ventricular Contraction (PVC)

Question 39

1) Progression to sustained Ventricular Tachycardia or
Ventricular Fibrillation.
2) Sudden cardiac death in those with underlying structural heart disease.

Answer 39

Complications: Premature Ventricular Contraction (PVC)

Question 40

If asymptomatic send MEDADVICE message and possibly
retain. If symptomatic MEDEVAC.

Answer 40

Disposition: Premature Ventricular Contraction (PVC)

Question 41

1) Totally disorganized depolarization of small areas of the ventricular myocardium.
2) No effective ventricular pumping and thus no cardiac output.
3) Life threatening arrhythmia.
4) Seen most commonly with severe ischemic heart disease.

EKG
1) Fine to course zigzag pattern without p waves or QRS complexes.

Symptoms
1) Patient will not have a pulse
2) Hypotensive
3) Unconsciousness
4) If a patient is awake and responsive

Answer 41

Ventricular Fibrillation

Question 42

Initiate ACLS Protocol for cardiac arrest.

Answer 42

Treatment: Ventricular Fibrillation

Question 43

1) Death
2) Anoxic brain injury.
3) Anoxic organ dysfunction.

Answer 43

Complications: Ventricular Fibrillation

Question 44

1) _______ is a polymorphic Ventricular tachycardia.
2) Primarily due to acquired or congenital QT interval
prolongation.
3) Most acquired prolonged QT due to many different classes of medications.
4) Can be triggered by hypomagnesemia, hypocalcemia, hypokalemia, starvation, anorexia nervosa, liquid protein diets, and hypothyroidism.

EKG
1) HR greater than 100 beats/min.
2) Wide QRS complex (greater than 0.12 seconds).
3) Frequent variations of the QRS axis, morphology, or both.

Symptoms
1) Palpitations
2) Lightheadedness, dizziness
3) Hypotension
4) Syncope
5) Sudden cardiac death

Answer 44

Torsades de Pointes

Question 45

1) IV, Monitors, Vitals, Oxygen if saturation < 94%.
2) Need to first determine if they have a pulse. If PULSELESS
then initiate ACLS Protocol.
3) IF they have a pulse then determine if they are stable or unstable.
4) IF stable then continue to monitor, Vitals every 5 minutes and 2 grams of Magnesium Sulfate IV, Check electrolyte panel and EKG if able.
5) IF unstable then proceed to synchronized cardioversion at 100 J then give 2 grams of Magnesium Sulfate IV.
6) Call for MEDEVAC to higher level of care.
7) Stop all medications that they are taking.

Answer 45

Treatment: Torsades de Pointes

Question 46

Magnesium Sulfate 2 grams IV over 10 minutes.

Answer 46

Medications: Torsades de Pointes

Question 47

1) Delayed or blocked conduction from the atrium to the ventricles.
2) 3 degrees of AV blocks.
3) AV Block = heart blocks.
4) Advanced Heart blocks = 2nd degree type II and 3rd degree heart blocks.

Answer 47

Atrioventricular (AV) Block

Question 48

a) Delayed AV conduction manifested by a prolonged PR interval.
b) It represents delayed conduction between the SA node and the AV node, not truly a heart block.
c) It is a benign finding, with no need to worry about it progressing into any worse block.

EKG:
Prolonged PR interval > 0.2 seconds is the only finding that defines the condition.

Symptoms: Mostly asymptomatic

Treatment: None warranted as it will not progress to any further arrhythmia or AV block.

No need to call for MEDADVICE or MEDEVAC, patient can go about their usual duty without any restrictions, no need to follow up on anything.

Answer 48

1st Degree AV Block

Question 49

a) This is commonly referred to a Wenckebach block.
b) Progressive prolongation of AV conduction until impulse is completely blocked.
c) In this rhythm the block is above the AV node.
d) Causes: Can be normal in athletes, increased vagal tone, ischemic heart disease, AMI, Cardiomyopathy, Viral myocarditis, Lyme Carditis, hyperkalemia, Hypo/Hyperthyroidism, medications (Beta blockers, Calcium channel blockers, antiarrhythmic drugs)

e) EKG
(1 Progressive PR interval prolongation until a QRS complex is not conducted.
(2 This represents failure of a conducted atrial beat to reach the ventricle.
(3 QRS complex is narrow (because the disease is above the AV node).
f) Symptoms
(1 Typically patient will only be symptomatic if they are bradycardic with HR < 50 beats per min.
(2 If bradycardic then may have lightheadedness, dizziness, presyncope, syncope or evidence of shock.

Answer 49

2nd Degree AV Block Type I

Question 50

(1 IV, Monitor, Vitals, Oxygen if saturation < 94%.
(2 Evaluate for any signs of being unstable: If unstable then administer Atropine 0.5mg IV and prepare for transcutaneous pacing.
(3 If stable and bradycardic start looking for causes.
(4 If stable, normal HR, and asymptomatic - look for possible causes and if no serious causes then okay to continue duty. Call for MEDADVICE.
(5 If stable, normal HR, but symptomatic then place on monitor, vitals, and observe. Call for MEDADVICE.

Answer 50

Treatment: 2nd Degree AV Block Type I

Question 51

What Rythem?

Atropine 0.5 mg IV bolus and can repeat every 3-5 minutes if needed for a total max dose of 3 mg.

If Atropine ineffective then can use Dopamine IV 210
mcg/kg/min.

Epinephrine IV 2-10 mcg/min.

If Atropine does not work, then transcutaneous pacing. set it to 80 beats/min

Answer 51

Medications: 2nd Degree AV Block Type I

Question 52

(1 _______ usually imply structural heart damage to the nodal conduction system and are usually permanent.
(2 They have a high likelihood of progressing to a 3rd degree AV block.
(3 Typically the block is just below the AV node in the HIS bundle.
(4 Because of the potential for progression to 3rd degree block you MUST prepare transcutaneous pacing. IF pacing unavailable use Dopamine Infusion or Epinephrine infusion (same doses as above).
(5 Must identify and treat any underlying causes increased vagal tone, AMI, drugs depressing conduction.

EKG
(1 PR interval remains unchanged prior to a P wave that fails to
conduct to the ventricles.
(2 Because the disease is below the AV node the QRS complex tends to be more prolonged (> 0.10 seconds in duration).

Symptoms
(1 Fatigue
(2 Dyspnea
(3 Chest pain
(4 Presyncope or syncope
(5 Sudden cardiac arrest

Answer 52

2nd Degree AV Block Type II

Question 53

(1 ABCs, IV, Monitor, Vitals, Oxygen if saturation < 94%.
(2 Evaluate for any signs of being unstable: (changes in mental
status, ischemic chest discomfort, hypotension, signs of shock,
acute heart failure) if unstable then administer Atropine 0.5mg IV
and prepare for transcutaneous pacing.
(3 If Atropine ineffective then can use Dopamine IV 2-20
mcg/kg/min.
(4 If signs of heart failure use either Dobutamine 5-20 mcg/kg/min or Epinephrine 2-10 mcg/min.
(5 Regardless of treatment you need to transcutaneous pace the
patient.
(6 Call for MEDEVAC to a higher level of care to a cardiologist and permanent pacemaker
(7 Obtain a 12 lead EKG if possible to evaluate for AMI, check
electrolyte levels.

Answer 53

Treatment: 2nd Degree AV Block Type II

Question 54

(1 Also known as complete heart block due to no AV conduction.
(2 There is complete disassociation of P waves and QRS complexes.
(3 Occurs in up to 8% with AMI.
(4 Usually this leads to inadequate cardiac output to maintain
perfusion to vital organs and patients present unstable with periods of ventricular asystole.
(5 Causes are similar to 2nd Degree AV blocks, especially cardiac
ischemia.

EKG
(1 Patient’s will have evidence of atrial (p waves) and ventricular
(QRS complex) activity which are independent of each other on
the EKG.
(2 There will be no association or pattern to PR intervals.
(3 Disease in 2/3 of patient’s is at the AV node which leads to narrow qrs

Symptoms
(1 Fatigue
(2 Dyspnea
(3 Chest pain
(4 Presyncope or syncope
(5 Sudden cardiac arrest

Answer 54

3rd Degree AV Block

Question 55

(1 ABCs, IV, Monitor, Vitals, Oxygen if saturation < 94%.
(2 Evaluate for any signs of being unstable: if unstable then
administer Atropine 0.5 mg IV and prepare for transcutaneous
pacing.
(3 If Atropine ineffective then can use Dopamine IV 2-10
mcg/kg/min.
(4 If signs of heart failure use either Dobutamine 5-20 mcg/kg/min or Epinephrine 2-10 mcg/min.
(5 Regardless of treatment you need to transcutaneously pace the
patient.
(6 Call for MEDEVAC to a higher level of care to a cardiologist and
permanent pacemaker.
(7 Obtain a 12 lead EKG if possible to evaluate for AMI, check
electrolyte levels.

Answer 55

Treatment: 3rd Degree AV Block