Tachy + Bradycardias + Arrhythmias Flashcards Preview

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Flashcards in Tachy + Bradycardias + Arrhythmias Deck (47)
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1
Q

Adult tachycardia algorithm: initial steps

A

A-E
ECG
Identify reversible causes (4Ts + 4Hs)
Any adverse signs?

2
Q

What are the adverse signs in tachycardias?

A

Shock
Syncope
MI
Heart failure

3
Q

What do you do when there are adverse signs in a tachycardia?

A
Pt unstable
Synchronised DC shock
Amiodarone 300mg over 10-20 mins
Repeat shock
Amiodarone 900mg over 24hrs
4
Q

What to do if there are no adverse signs in a tachycardia?

A

Assess whether tachycardia is broad, narrow, regular or irregular

5
Q

What to do with a broad, regular tachycardia?

A

If VT or unsure:
Amiodarone 300mg over 24hrs then 900mg over 24hrs
If SVT w/ BBB: treat as regular narrow complex (Vagal)

6
Q

What to do with a broad, irregular complex?

A

Seek help!! AF w/ BBB

7
Q

What to do with a narrow, regular tachycardia?

A
Vagal manouvres (vasalva, carotid sinus massage, blowing into syringe)
Adenosine 6mg rapid IV - if no effect give another 12mg, then another 12mg
8
Q

What happens after treating a narrow, regular tachycardia?

A

If sinus rhythm achieved = probably re-entry paroxysmal SVTIf not achieved = could be atrial flutter - control with BB

9
Q

What to do with a narrow, irregular tachycardia?

A

Probably AF - treat rate with BB or dilitiazem
Digoxin or amiodarone in HF
Assess thrombosis risk

10
Q

Management of a polymorphic VT (eg Torsades de Point)?

A

Magnesium 2g

11
Q

When is amiodarone used?

A

Broad complex QRS arrhythmias

12
Q

ECG findings for VF

A

Small fib waves

13
Q

Management of AVRT + AVNRT (stable vs unstable)

A

If stable - vagal then adenosineIf unstable, synchronised cardioversion then amiodarone

14
Q

What is AVNRT?

A

Electrical activity circuits around the AV node

Caused by fast + slow fibres

15
Q

What is AVRT?

A

AV re-entrant tachycardia
Due to accessory pathway between ventricles + atria
Signal is conducted back to atria so atria contract before SAN sends next impulse
Causes fast heart rate
EG Wolff Parkinson White - accessory pathway is bundle of Kent

16
Q

What is SVT?

A

Narrow complex

Any impulse beginning above the bundle of His - any tachycardia that is not ventricular in origin (AF/ flutter/ AVRT)

17
Q

How can you distinguish between different forms of tachycardias on ECG?

A
Broad or narrow?
Broad irregular = AF with BBB
Broad regular = VT or SVT with BBB
Narrow Reg: VT, SVT
Irregular: AF
18
Q

Types of ventricular tachycardia

A

Monomorphic VT = short circuit coming from 1 place in the heart
Polymorphic VT = Torsades de Point, due to long QT interval

19
Q

S+S of AVNRT

A

Palpitations, dizziness, light headedness, SOB

Sudden onset

20
Q

AVNRT on ECG

A

Sudden onset, following atrial premature beat, spontaneous termination with AV block in absence of premature atrial beat
Loss of P waves

21
Q

Management of AVNRT

A

Stable = vagal maneuvres, adenosine, then verapamil, diltiazem, metoprolol or digoxin
Unstable = cardioversion
Long term = BB, diltiazem, digoxin
2nd line = flecainide, propafenone

22
Q

Bradycardia guidelines - initial step

A
Assess using A-E approach 
Any adverse features:
Shock
Syncope 
Myocardial ischaemia 
HF
23
Q

Bradycardia guidelines - what to do if adverse features are present?

A

Atropine 500mcg IV
If satisfactory response - move onto assessing risk of asystole

If not, consider interim measures: 
Atropine 500mcg IV repeat to max of 3mg 
OR 
Transcutaenous pacing 
OR 
Isoprenaline 5mcg min IV
Adrenaline 2-10mcg min IV 

Ultimately - arrange transvenous pacing!!

24
Q

Bradycardia guidelines: what to do if there are no adverse features?

A
Assess risk of asystole:
Recent asystole 
Mobitz II AV block 
Complete heart block w/ broad QRS 
Ventricular pause >3s
25
Q

Bradycardia guidelines: what to do if there is no risk of asystole?

A

Continue obs

26
Q

Bradycardia guidelines: what to do if there is a risk of asystole?

A
Consider interim measures: 
Atropine 500mcg IV repeat to max of 3mg 
OR 
Transcutaenous pacing 
OR 
Isoprenaline 5mcg min IV
Adrenaline 2-10mcg min IV

Ultimately - arrange transvenous pacing!!

27
Q

Types of bradycardias

A
Sinus bradycardia 
Sinoatrial block 
Sinus arrest 
AV block 
Junctional rhythm 
Idioventricular rhythm
28
Q

Types of regular narrow complex tachycardias

A
Sinus tachycardia 
Atrial tachycardia 
Junctional tachycardia 
AVNRT 
AVRT 
Atrial flutter
29
Q

Types of regular wide complex tachycardias

A

SVT with BBB
VT
AVRT

30
Q

Types of irregular narrow complex tachycardias

A

AF
Atrial flutter with variable block
Premature atrial contraction

31
Q

Types of irregular wide complex tachycardias

A

AF with BBB
Atrial flutter with variable + BBB
Polymorphic VT (Torsades de Point)
Premature ventricular contraction

32
Q

Management of sick sinus syndrome

A

Atropine

33
Q

What are the types of premature beats?

A

Premature atrial contraction

Junctional premature beat - originates from vicinity of AV nodes

34
Q

Describe WPW

A

Congenital defect of Bundle of Kent causing AVRT + AF

35
Q

ECG changes in WPW

A

PR interval <120
Slurred upstroke of QRS (delta wave)
Widened QRS

36
Q

Describe AF in WPW

A

> 200 blm ventricular rate - AF is conducted through bypass tract

37
Q

What are the types of AVRT?

A
Orthodromic = stimulus from premature complex travels up bypass tract + down AV node with narrow complex 
Antidromic = signal goes up AV node + down bypass tract, causes wide + abnormal QRS
38
Q

Management of AVRT

A

Same as AVNRT except avoid digoxin + verapamil

Long term = ablation

39
Q

What is a premature ventricular contraction?

A

Usually benign but can be significant if consecutive or multiform, or if falling on T wave of previous beat

40
Q

ECG changes for premature ventricular contraction

A

ARS >120
No P wave
Bizarre QRS

41
Q

What is an accelerated idioventricular rhythm?

A

Ectopic ventricular rhythm with rate 50-100

Occurs in acute MI or heart disease

42
Q

What is Torsades de Point?

A

Variation of polymorphic VT that occurs with baseline QT prolongation
QRS complexes twist around baseline

43
Q

What drugs predispose to Torsades?

A
Anything that prolongs QT:
Quinidine
Sotalol
TCAs
Erythromycin 
Quinolones 
Antihistamines
44
Q

What electrolyte disturbances can cause Torsade de Point?

A

Hypokalaemia

Hypomagnesemia

45
Q

Management of Torsades de Point?

A

Magnesium, temporary pacing, isoproterenol

46
Q

What is a pre-excitation syndro,e?

A

AVRT + symptoms of tachyarrhythmia

eg WPW or LGL

47
Q

What is ortho vs antidromic?

A
Orthodromic = impulse goes down AVN up accessory pathway
Anti = impulse goes down accessory pathway and up AVN - dangerous because its uncontrolled