Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 5 - Cardiology > Arrhythmias > Flashcards

Arrhythmias Flashcards

1
Q

Cardiac arrest rhythms

A

Shockable:

  • Ventricular tachycardia
  • Ventricular fibrillation

Non-shockable rhythms:

  • Pulseless electrical activity
  • Asystole
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Cardiac arrest protocol

A

Assess rhythm - shockable vs non-shockable

CPR 30:2

Adrenaline 1mg

  • Give ASAP for non-shockable rhythms
  • After third shock in VF/VT
  • Repeat every 3-5m

Amiodarone 300mg
- Give after third shock in VF/VT
(- Further dose of 150mg after 5 shocks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Reversible causes of cardiac arrest

A

Four Hs, Four Ts

Hypoxia
Hypovolaemia
Hypo/hyperkalaemia
Hypothermia

Thrombosis
Tension pneumothorax
Tamponade
Toxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Tachycardia treatment summary

A

Unstable:

  • Consider up to 3 synchronised shocks
  • Consider amiodarone infusion

Stable with narrow complex (<0.12s QRS)

  • AF - rate control with beta blocker or CCB (or rhythm control if in 48h)
  • Atrial flutter - rate control with beta blocker
  • SVT - vagal manoeuvres and IV adenosine

Stable with broad complex (>0.12s QRS):

  • VT or unclear - amiodarone infusion
  • If previously confirmed SVT with BBB - give adenosine as for normal SVT
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the pathophysiology of atrial flutter?

A

Atrial flutter is caused by a “re-entrant rhythm” in either atrium.

This is where the electrical signal re-circulates in a self-perpetuating loop due to an extra electrical pathway.

This stimulates atrial contraction at 300bpm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is atrial flutter associated with?

A

HTN
IHD
Cardiomyopathy
Thyrotoxicosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Treatment of atrial flutter

A

Rate/rhythm control with beta blockers or cardioversion

Treat the reversible underlying condition (e.g. hypertension or thyrotoxicosis)

Radiofrequency ablation of the re-entrant rhythm

Anticoagulation based on CHA2DS2VASc score

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What causes SVT?

A

Electrical signal re-entering the atria from the ventricles.

Normally the electrical signal in the heart can only go from the atria to the ventricles.

In SVT the electrical signal finds a way from the ventricles back into the atria.

Once the signal is back in the atria it travels back through the AV node and causes another ventricular contraction.

This causes a self-perpetuating electrical loop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is paroxysmal SVT?

A

Situation where SVT comes and goes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Acute management of SVT

A

Valsalva manoeuvre

Carotid sinus massage

Adenosine

  • Slows conduction through the AV node
  • May cause brief period of asystole - however it is quickly metabolised and sinus rhythm should return

Alternative to adenosine is verapamil

DC cardioversion may be needed if medical treatment fails

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Adenosine key things to remember

A

Avoid in asthma, COPD, heart block and severe hypotension

Warn patient about the scary feeling of dying / impending doom when injected

Give ASAP into large cannula
- Initially 6mg, then 12mg and further 12mg if there is no improvement between doses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Recurrent episodes of SVT

A

Measures can be taken to prevent these episodes

Medication - beta blockers, CCBs or amiodarone

Radiofrequency ablation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is Wolff-Parkinson White syndrome?

A

Caused by extra electrical pathway connecting the atria and ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

ECG changes in WPW

A 
Short PR interval (<0.12s)
Wide QRS (>0.12s)

Delta wave - slurred upstroke to QRS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Definitive management of WPW, other treatment

A

Radiofrequency ablation of the accessory pathway is the definitive management

Medical therapy:

  • Sotalol
  • Amiodarone
  • Flecainide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is radiofrequency ablation? What conditions can it be used for?

A

Identifying the site of the arrhythmia and burning the abnormal area of electrical activity

These leaves scar tissue which will not conduct impulses

Can be curative and used in:

  • AF
  • Atrial flutter
  • SVT
  • WPW
17
Q

What is torsades de pointes?

A

A type of polymorphic VT

It looks like normal ventricular tachycardia on an ECG however there is an appearance that the QRS complex is twisting around the baseline.

The height of the QRS complexes progressively get smaller, then larger then smaller and so on.

18
Q

Who can torsades de pointes occur in?

A

It occurs in patients with a prolonged QT interval

19
Q

What causes prolonged QT?

A

Long QT syndrome - inherited

Medications - antipsychotics, citalopram, flecainide, amiodarone, macrolide antibiotics e.g. erythromycin

Electrolyte disturbances e.g. low K, Mg, Ca

20
Q

Acute management of Torsades de Pointes

A

Correct the cause - stop causative medications, correct electrolyte disturbances

Magnesium sulphate infusion

May need defibrillation if VT occurs

21
Q

What is the risk of Torsades de Pointes?

A

It can progress into VT and cardiac arrest

22
Q

Long term management of prolonged QT syndrome?

A 
Avoid medications that prolong the QT interval
Correct electrolyte disturbances
Beta blockers (not sotalol)
Pacemaker or implantable defibrillator
23
Q

What are ventricular ectopics? Presentation?

A

Premature ventricular beats causes by random electrical discharges from outside the atria.

Presentation:
- Random brief palpitations

ECG - will show individual random, abnormal, broad QRS complexes on a background of a normal ECG.

24
Q

Management of ventricular ectopics

A

Bloods -

  • FBC (check for anaemia)
  • U&Es (check for electrolyte disturbance)
  • TFTs

Reassurance and no treatment in otherwise healthy people

Seek expert advice in patients with background heart conditions or other concerning features or findings (e.g. chest pain, syncope, murmur, family history of sudden death)

25
Q

Types of heart block

A

First degree - Prolonged PR interval (>0.2s or 5 small squares)
- All P waves followed by QRS

Second degree:

  • Type 1 - PR interval gradually increases until non-conducted P wave
  • Type 2 - PR interval doesn’t lengthen but there is a set ratio of P waves to QRS

Third degree
- Complete dissociation between atria and ventricles

26
Q

2:1 heart blocks

A

2 P waves for every QRS

Can be caused by Mobitz type 1 or type 2 - difficult to tell which

27
Q

What is the risk with Mobitz type 2 and third degree heart block?

A

Risk of asystole

28
Q

Treatment of AV node blocks/bradyarrhythmias

A

If unstable or risk of asystole (Mobitz Type 2, complete heart block or previous asystole):
- Atropine 500mcg IV

If no improvement:

  • Further atropine doses up to 3mg
  • Other inotropes e.g. isoprenaline
  • Transcutaneous cardiac pacing
29
Q

Common causes of AV node block

A

IHD - most common

Also - medications (BB, CCBs, digoxin), electrolyte imbalances, post-cardiac surgery,

30
Q

What is the definitive treatment of Mobitz type 2 and complete heart block?

A

Pacemaker + ICD (implantable cardioverter defibrillator)

Year 5 - Cardiology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions