10 - Arrhythmias P. 1

Question 1

Native latent pacemakers

Answer 1

Sinoatrial node - 60-100 bpm
Atrioventricular junction - 40-60 bpm
Purkinje system - 20-40 bpm

Question 2

Action potential phases

Answer 2

Phase 0 - resting state (-80mV)
—cell repol —
Phase 1 - na channels close = NA flux ceases
Phase 2 - k channel opens Ca++ flux continues - plateau phase
Phase 3 - Ca++ closes, K+ fluc out continues
—gradual and spontaneous depol—
Phase 4 - K+ channel closed, active transport of Na+ and K+ return to resting state concentration

Question 3

Arrhythmias are generated by?

Answer 3

1. Altered impulse formation

2. Altered impulse conduction

Question 4

Altered impulse formation examples

Answer 4

• altered normal automaticity
• increased sinus node automaticity (sympathetic)
• increased sinus node automaticity (parasympathetic)
• escape rhythms
• ectopic beats & rhythms
• abnormal automaticity
• triggered activity
• early after depol
• delayed after depol

Question 5

Altered impulse conduction examples

Answer 5

• Conduction block
• transient vs permanent
• unidirectional/bidirectional
• functional/fixed
• reentry
• primarily unidirectional
• includes accessory pathways (WPW)
• multidirectional (unstable pathway_

Question 6

Supraventricular arrhythmias

Answer 6

PAC
Ectopic Atrial Rhythm
MAT
Atrial Flutter
Atrial Fibrillation

Question 7

Junctional arrhythmias

Answer 7

(Nodal)
PJC
Junctional Rhythm
AV node re-entry tachy (AVNRT)
AV re-entry tachycardia (AVRT)

Question 8

Ventricular arrhythmia

Answer 8

PVC
Idioventricular rhythms
V tach
Polymorphic ventricular tachycardia (torsades)
V Fib

Question 9

If the monitor looks terrible but the pt looks fine?

Answer 9

Treat the pt no the monitor

Question 10

Assess stability of pt

Answer 10

HOTN
Alter mental
Shock
Ischemic chest discomfort
Acute HF

Follow ACLS alogrithms

Question 11

Tachycardia ACLS protocol

Answer 11

O2, EKG
Assess stability
Unstable - cardiovert
Stable - fix causes

Question 12

Bradycardia ACLS protocol

Answer 12

O2 ekg
Assess stability

Stable - look for the why
Unstable - ATROPINE, dopamine, EPI

Question 13

Shock, shock, everybody shock, & another shock

Answer 13

V fib pulseless V tac ACLS

Shock 
Shock 
Epi
Shock 
Amnioterone 
Shock

Question 14

Reversable causes of MI

H’s and T’s

Answer 14

Hypovelemia
Hypoxia
Hydrogen ion (acidosis)
Hypo-hyperkalemia
Hypothermia
Tension pneumothorax
Tamponade, cardiac
Toxins
Thrombosis, pulmonary
Thrombosis, Coronary

Question 15

Cardiac arrest drugs

Answer 15

Epinephrine - 1mg q 3-5 min
Amiodarone -
- 1st dose = 300 mg bolus
- 2nd dose = 150 mg

Question 16

Cardiac arrest shock therapy

Answer 16

1st
- Biphasic 120-200J
2nd and subsequent
- Monophasic 360J

Question 17

Approach for stable arrhythmias

Answer 17

ID arrhythmia
Mechanism 
Consequences
Treatment (best for this one)
Patient HX 
PE
Diagnostics

Question 18

Stable arrhythmias diagnostic tests

Answer 18

Lab - CBC, TSH, Electroyltyes, Drugs, HCG
Electrical - ECG, Holter/event/implantable
CXR
TTE
Treadmill
Tilt-table
Electrophysiologic testing

Question 19

Implantable pacemaker indications

Answer 19

Heart block
Sinus node dysfunction
Syncope
Dilated cardiomyopathy

Question 20

Cardioverter-defibrillator indications

Answer 20

Non sustained VT
Spontaneous VT
Cardiac arrest survivors
Syncope of undetermined etiology (when pharm fails)

Question 21

Types of pacemakers

Answer 21

Temporary
-Transcutaneous
-Transvenous
Permanent
-ventricular
-dual chamber
-biventricular

ICD/Cardioverter

Question 22

Temp pacemakers

Answer 22

Reversible bradycardia
Acute rheumatic fever
Pending surgery

*dont leave the hospital

Question 23

Permanent pacemaker types

Answer 23

Ventricular

• single chamber
• dual chamber
• atria and ventricle

Biventricular
-both ventricles

Question 24

AICD

Answer 24

Automated implantable cardioverter defribillator

Pts at risk for SCD

• CAD
• depressed LV function
• runs of VT
• LVEF <30%
• long QT, brugada syndrome

Question 25

Pacemaker spike before QRS

Answer 25

Ventricular pacing

Question 26

Pacemaker spike before p and before QRS

Answer 26

Dual chamber

Question 27

Pacemaker spike in 2,3,AVF?

Answer 27

L ventricle

Question 28

Pacemaker spike before p

Answer 28

Atrial pacing

Question 29

2 pacemaker spikes before QRS, none before p

Answer 29

Dual chamber pace