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YEAR 3 TCD > WEEK 7 - palpitations > Flashcards

WEEK 7 - palpitations Flashcards

1
Q

where does the pericardial cavity sit?

A

between the parietal and visceral layers of the serous pericardium

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2
Q

Cardiomyocyte ________ in unison in order to provide effective pump action to ensure adequate blood _________ of the organs and tissues. Cardiomyocyte make up the bulk of the volume of the heart but constitute only ______ of the total cell number.

Intercalated discs (gap junction) provide an electrical junction from one cell to the next. They transmit _______ currents from one cell to the next. Intercalated discs are made up of 6 hollow tubes (________) that provides an intercellular gap enabling the ___________ to act as an electrically continuous sheet and all myocytes to be activated simultaneously.

Intercalated discs (desmosomes) provide a structural attachment from one cell to the next. They ‘glue’ cells together. Glycoproteins called _________ span the 25nm gap between the cell membranes, and ______ forms the intermediate filaments.

Transverse tubules (t-tubules) are invaginations of the cell membrane which run into the _______ of the cell. They transmit the electrical stimulus rapidly into the interior of the cell. Transverse tubules promote the synchronous activation of the whole depth of the cell despite the fact that the signal to contract is relayed across the external membrane.

A
  • contract
  • perfusion
  • 30-40%
  • ionic
  • connexon
  • myocardium
  • cadherins
  • desmin
  • interior
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3
Q
A
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A
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5
Q

inflow of what depolarises the membrane and causes a rise in membrane voltage?

A

Na+

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6
Q

rapid outflow of what returns the membrane potential to its resting potential?

A

K+

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7
Q

Lead I detects electrical activity from which aspect of the heart?

A

left lateral

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8
Q

Lead aVR detects electrical activity from which aspect of the heart?

A

right atrium

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9
Q

Lead V6 detects electrical activity from which aspect of the heart?

A

left ventricle

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10
Q

what does each aspect of an ecg look at?

A
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11
Q

what are narrow complex vs broad complex tachycardias?

A
  • Narrow: Atrial fibrillation, Supraventricular tachycardia eg atrial flutter
  • Broad: Ventricular fibrillation
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12
Q

what 3 things could you find on examination with thyrotoxicosis?

A

goitre, tremor and exophthalmos

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13
Q

what 2 things could you find on examination with anaemia?

A

pallor of creases, conjunctivae

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14
Q

Flip-flopping – the palpitations are thought to be caused by _____ ______ such as supraventricular or ventricular premature contractions. The flip-flop sensation is thought to result from the forceful contraction following the pause and the sensation that the heart is stopped results from the pause.

A

extra systoles

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15
Q

Rapid fluttering – result from a sustained ventricular or supraventricular arrhythmia. Furthermore, the sudden cessation of this arrythmia can suggest ________ __________ __________. This is further supported if the patient can stop the palpitations by using _________ manoeuvres.

A

paroxysmal supraventricular tachycardia

Valsalva

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16
Q

The rhythm of the palpitations may indicate the aetiology of the palpitations (irregularly irregular palpitations indicate _____ _______ as a source of the palpitations). An irregular pounding sensation in the neck can be caused by ____________ _________, and the subsequent atria are contracting against a closed tricuspid and mitral valves, thereby producing _______ _ _____.

A
  • atrial fibrillation
  • atrioventricular dissociation
  • cannon A waves
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17
Q

Palpitations induced by exercise could be suggestive of _______________, ___________ or ____________.

A

cardiomyopathy, ischemia or channelopathies

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18
Q

Palpitations can occur during times of catecholamine excess, such as during exercise or at times of stress. The cause of the palpitations during these conditions is often a sustained __________ tachycardia or ____________ ____________. ____________ tachycardias can also be induced at the termination of exercise when the withdrawal of catecholamines is coupled with a surge in the _____ tone.

Many psychiatric conditions can result in palpitations including depression, generalized anxiety disorder, panic attacks, and somatization.

A
  • supraventricular
  • ventricular tachyarrhythmia
  • supraventricular
  • vagal
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19
Q

according to NICE, if the cause of the palpitations remains unclear, what should you do if…..

  1. If symptoms are relatively infrequent (less than once a week) and last for an hour or more
  2. If symptoms are short lived but frequent
  3. If symptoms are short lived and infrequent
A

If the cause of the palpitations remains unclear:

If symptoms are relatively infrequent (less than once a week) and last for an hour or more, advise the person to attend an Accident and Emergency department, or their GP surgery, for an electrocardiogram (ECG) during the next episode. Provide a letter to be given to the healthcare professional requesting an ECG immediately on presentation during an episode.

If symptoms are short-lived, arrange ambulatory monitoring in primary care if available, or refer to cardiology. The type of monitoring required is dependent on the frequency and duration of symptoms:

If symptoms are short lived but frequent (for example, daily), a 24-hour or 48-hour Holter monitor is appropriate.
If symptoms are short lived and infrequent (for example, less than once a week), a self-activated recorder or an event monitor is appropriate.

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20
Q

what are palpitations?

A

Palpitations are defined as rapid pulsations or abnormal rapid or irregular beating of the heart. They are common and non-specific. The cause of palpitations could be benign or more life threatening

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21
Q

how can the causes of palpitations be defined according to their underlying pathogenesis?

A
  • High output states: Anaemia or pregnancy
  • Structural cardiac causes: valvular heart disease, ischaemic heart disease, hypertension
  • Catecholamine excess: high caffeine, illicit drugs, stress, anxiety
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22
Q

what is an arrhythmia?

A

an abnormality of the heart’s rhythm. It may beat too slowly, too quickly, or irregularly. These abnormalities range from a minor inconvenience or discomfort to a potentially fatal problem. Arrhythmias or heart rhythm problems are experienced by more than 2 million people in the UK.

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23
Q

bradycardia = <__bpm
tachycardia = >__bpm

A
  • 60
  • 100
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24
Q

what can cause bradycardias?

A

occur when depolarisation FAILS to initiate or conduct properly

  • SAN disease
  • heart block (AVN, His-bundle)
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25
Q

what can cause tachycardias?

A

occur when there is ABNORMAL depolarisation occurring in the heart

  • enhanced automaticity
  • reentry
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26
Q

what is SA node disease and what are the various forms?

A

when the SA node fails to act as the ‘pacemaker’

  • sinus bradycardia
  • sinus pause
  • sinoatrial exit block (heart block)
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27
Q

what does this show?

A

sinus bradycardia

Sinus bradycardia occurs on an ECG when there is a normal upright P wave in lead II ― sinus P wave ― preceding every QRS complex with a ventricular rate of less than 60 beats per minute.
Many normal causes like in athletes or when asleep

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28
Q

what does this show? describe the condition

A

sinus pause

  • Sinus pause describes a condition where the SA node fails to generate an electrical impulse for what is generally a brief period of time.
  • Patients who have sinus pauses may complain of missed or skipped beats, flutters, palpitations, hard beats or may feel faint, dizzy or lightheaded or experience a syncopal episode (passing out). Frequent pauses would heighten these symptoms. This is a result of patients actually missing or dropping beats. Obviously, if the heart misses a beat, blood does not flow during that time period resulting in a lack of oxygen or perfusion throughout the body.
  • Treatment may involve the use of medications or the use of a temporary or permanent pacemaker.
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29
Q

what does this show? describe

A

sinoatrial exit block (heart block)

During sino-atrial exit block, the depolarizations that occur in the sinus node cannot leave the node towards the atria. They are blocked. On the ECG this is expressed as a pause. SA exit block can be distinguished from sinusarrest because the pause in SA exit block is a multiple of the P-P interval that preceded the pause.

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30
Q

what is first degree heart block?

A

slow conduction through AV node

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31
Q

what are the 2 types of 2nd degree heart block?

A
  • Wenckebach or Mobitz type I — Av conduction becomes slower and slower until it misses a beat
  • Mobitz type II — fixed block - usually 2:1
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32
Q

what is 3rd degree heart block?

A

complete heart block — no conduction to the ventricles

an escape pacemaker takes over from the His-bundle/bundle branch

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33
Q

what does this show?

A

2nd degree heart block type I

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34
Q

what does this show?

A

3rd degree heart block

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35
Q

what does this show?

A

2nd degree heart block type II

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36
Q

what does this show?

A

1st degree heart block

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37
Q

how to remember heart block mnemonic

A
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38
Q

what is automaticity?

A

an area of myocardial cells depolarise faster than the SA node. this may be atrial or ventricular issue. most occur at a single ‘focal’ site

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39
Q

what is reentry?

A

an electrical pathway that is not supposed to be there, connecting 2 areas that should not be connected. abnormal electrical connections can be congenital, or they can form because of heart disease. if such a connection exists, it can form an electrical circuit

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40
Q

what are the 2 types of tachycardia?

A

narrow complex (SVT) and broad complex (VT):

  • supraventricular tachycardia (SVT) is a heart condition where the heart suddenly beats much faster than normal. this type of tachycardia originates from faulty electrical impulses in the upper part of the heart, rather than from the ventricles
  • ventricular tachycardia (VT) is defined as a sequence of three or more ventricular beats. the frequency must be higher than 100bpm, mostly it is 110-250 bpm
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41
Q
A

(AVNRT = atrioventricular nodal reentrant tachycardia)

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42
Q

what does this show?

A

atrial flutter

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43
Q

what does this show?

A

atrial tachycardia

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44
Q

what does this show?

A

atrio-ventricular reentry tachycardia (AVRT)

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45
Q

what does this show?

A

AF

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46
Q

what does this show?

A

AVNRT

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47
Q
A
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48
Q

what does this show?

A

ventricular fibrillation

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49
Q

what does this show?

A

ventricular tachycardia

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50
Q
A
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51
Q

what is Wollf-Parkinson-White (WPW) syndrome?

A

a supraventricular tachycardia (SVT) that uses an atrioventricular (AV) accessory tract. The accessory pathway may also allow conduction during other supraventricular arrhythmias, such as atrial fibrillation or flutter. The majority of patients with ECG findings of pre-excitation do not develop tachyarrhythmias.

WPW syndrome is relatively common and found in 1-3 people per 1,000 population. WPW syndrome is found in all ages, although it is most common in young, previously healthy people.

It has been linked to Sudden Cardiac Death in children and young adults.

52
Q

WPW syndrome is classified into what two types according to the ECG findings?

A

type A = the delta wave and QRS complex are predominantly upright in the precordial leads. the dominant R wave in lead V1 may be misinterpreted as RBBB

type B = the delta wave and QRS complex are predominantly negative in leads V1 and V2 and positive in the other precordial leads, resembling LBBB

53
Q

what are vagal manoeuvres?

A

Vagal manoeuvres are physical actions that make your vagus nerve act on your heart’s natural pacemaker, slowing down its electrical impulses. Your vagus nerve — which goes from your brainstem to your abdomen — plays a major role in your parasympathetic nervous system, which controls a number of things in your body, including heart rate.

They are a low-risk, low-cost way to slow down a heart rate that’s too fast.

54
Q

Vagal manoeuvres (most commonly the Valsalva manoeuvre) can be used to distinguish between what?

A

ventricular tachycardia and supraventricular tachycardia by slowing the rate of conduction at the SA or AV nodes

55
Q

Vagal manoeuvres (most commonly carotid sinus massage) are used to diagnose what?

A

carotid sinus hypersensitivity

56
Q

Therapeutic: Vagal manoeuvres are the first-line treatment of hemodynamically stable ___________________, serving to slow down or terminate the arrhythmia. Vagal manoeuvres have a reported success rate of conversion to _____ rhythm for SVT around __-__%, possibly being higher for _____ (an SVT associated with a bypass tract). Whereas the modified Valsalva manoeuvre is most effective in adults, cold water immersion may be preferred as a safe, effective, and non-invasive treatment for paediatric SVT

A
  • supraventricular tachycardia
  • sinus
  • 20-40%
  • AVNRT
57
Q

describe the Valsalva manoeuvre

A

While lying on your back, take a deep breath and act like you’re exhaling but with your nose and mouth closed for 10 to 30 seconds. It should feel like trying to breathe air out into a blocked straw.

58
Q

describe the diving reflex

A

While sitting, take several deep breaths, hold your breath and then quickly put your whole face into a container of ice water. Keep your face submerged as long as you can. The alternative approach is putting a bag of ice water or an ice-cold, wet towel against your face.

59
Q

describe the carotid sinus massage

A

Lie on your back with your head turned to one side. The doctor will use their fingers to push on your carotid sinus for five to 10 seconds. If it doesn’t work, they can try again after a minute or try the other side of your neck

60
Q

when should a patient not do vagal manoeuvres?

A

Do not do vagal manoeuvres if patient is unstable, meaning they have:
- Low blood pressure
- Chest pain
- Shortness of breath
- A shortage of oxygen in their body
- An inability to get enough blood to their organs

61
Q

DVLA and arrhythmias?

A

In the UK, Driver and Vehicle Licensing Agency (DVLA) advice is as follows:

Group 1 (car or motorcycle):
- Must stop driving if the arrhythmia has caused or is likely to cause incapacity.
- Driving may be permitted when the underlying cause has been identified and the arrhythmia has been controlled for at least four weeks.

Group 2 (lorry or bus):
- Disqualifies from driving if the arrhythmia has caused or is likely to cause incapacity. DVLA must be informed.
- Driving may be permitted when:
- The underlying cause has been identified.
- The arrhythmia is controlled for at least three months.
- The LV ejection fraction is ≥40%.
- There is no other disqualifying condition.

62
Q

how is AF diagnosed on ECG?

A

AF is an ECG diagnosis characterised by

1) an irregular RR-interval and
2) absent or no p waves occurring for more than 30s (definition of sustained is more than 30s).

63
Q

AF is disorganised electrical activity within the atria (fibrillating) with an atrial rate of >____ bpm. This gives rise to the absent or abnormal __ waves (sometimes called fibrillation waves). The atrioventricular (AV) node is usually unable to conduct at such rapid rates and consequently there is a degree of ______. During AF the ventricular conduction is random and hence it gives rise to the irregularity of the ventricular beats (irregular __ interval).

A
  • 300
  • p
  • AV block
  • RR
64
Q

_______________________ (episode lasting between 30s up to 1 week) is a common cause of intermittent palpitations. AF usually begins with short, infrequent episodes of _____ which are often asymptomatic termed ‘silent’. A patient may then start to develop symptoms and eventually an ECG at the time of symptoms can make the diagnosis. As the condition progresses the episodes of AF become more frequent and longer lasting. Eventually ___ may develop into persistent AF (episode lasting more than 1 week) or permanent AF. The term permanent AF indicates that the clinician and patient are both happy to accept being in AF and no further attempts are made to restore sinus rhythm.

A
  • Paroxysmal atrial fibrillation or PAF
  • PAF
  • PAF
65
Q

what is one major trigger for AF that has been identified?

A

pulmonary veins ectopy

in AF patients, during embryonic development, sleeves of atrial tissue abnormally extend into the pulmonary veins. Ectopy arising from cardiomyocytes within one or more pulmonary veins can enter the left atrium and trigger AF, as well as sustain the arrhythmia

66
Q

AF is not usually considered a life-threatening arrhythmia and it is unlikely to result in a cardiac arrest (for example compared to ventricular tachycardia), but patients with AF have an increased mortality risk mainly due to what 2 things?

A

stroke and heart failure

AF increases the risk of stroke five-fold, and strokes due to AF are usually more severe and disabling. In some patients AF can impair the heart function and result in heart failure with reduced left ventricular systolic function. The risk of heart failure is increased when the ventricular rates are rapid and poorly controlled (i.e., >100 bpm). Approximately 20% of patients with atrial fibrillation will also have heart failure.

67
Q

what are the three important aspects of AF management?

A
  1. symptom control
  2. stroke prevention
  3. heart failure
68
Q

what is the HAS-BLED score? same as ORBIT score

A

scoring system to identify major bleeding risk in patients with AF

69
Q

patients with a HASBLED score of ___ or more are deemed high risk and require close monitoring

A

3

70
Q

Oral anticoagulation is recommended in patients with a high stroke risk (i.e., CHA2DS2VASc score of __ or more in women, __ or more in men)

A
  • 2
  • 1
71
Q

what anticoagulation is recommended first line for AF?

A

DOACs — they all have similar efficacy and safety profile - choice will depend on patient preferences (once daily or twice daily medication) as well as renal function

72
Q

what doac is licensed for use in patients with chronic kidney disease?

A

apixaban

73
Q

in AF, what medications are used for rate control?

A

beta blockers

74
Q

in AF, what medications are used to maintain sinus rhythm?

A

amiodarone, flecainide

75
Q

A DC cardioversion is not a definitive treatment; although it is the most effective way of restoring sinus rhythm it does not prevent the recurrence of AF. The inability to restore sinus rhythm (even for one beat) despite at least ___ weeks of ________ therapy would be defined as an unsuccessful DC cardioversion. In these cases, a rate control approach would be recommended.

A
  • 4
  • amiodarone
76
Q

although the mechanisms involved are not fully understood, what seems to be the commonest trigger for AF?

A

ectopy arising from one or more of the pulmonary veins

77
Q

what are the 2 commonest causes of sustained palpitations?

A

atrial fibrillation and supraventricular tachycardia (SVT)

78
Q

what is the most common cause of non-sustained palpitations?

A

ectopics — can be supraventricular or ventricular in origin

79
Q

what is Torsades des Pointes?

A

a type of VT that is a rare but potentially life threatening arrhythmia that can cause non-sustained symptoms

80
Q

look on goodnotes at adult tachycardia algorithm

A

ok

81
Q
A

CHA2DS2VASc, ORBIT and HASBLED

82
Q

apixaban, dabigatran, edoxaban and rivaroxaban MoAs

A

apixaban, edoxaban and rivaroxaban = factor Xa inhibitor

dabigatran = direct thrombin inhibitor

83
Q

what should patients with mechanical heart valves or moderate to severe rheumatic mitral stenosis be offered instead of doacs?

A

warfarin

84
Q

what are the main factors used to help decide between a rate versus rhythm control strategy for patients with AF?

A
85
Q

what is first line rate control treatment?

A

beta blockers — start with a low dose and uptitrate according to HR and BP. cautions use in patients with acute heart failure or elderly due to risk of hypotension

86
Q

what is second line treatment for rate control?

A

calcium channel blockers eg. diltiazem or verapamil

87
Q

in who should calcium channel blockers be avoided?

A

patients with left ventricular systolic dysfunction (because it has a negative inotropic effect)

88
Q

when can digoxin be used? what should be checked and monitored?

A

This can be added in if rate poorly controlled despite first line or second line. Ensure you check potassium (risk of toxicity in hypokalaemia) and monitor renal function. Levels can be taken to minimise risk of toxicity.

89
Q

when would a permanent pacemaker be used?

A

Useful in patients with tachy-brady syndrome to allow introduction of medications to treat tachy episodes. It can be combined with an AV node ablation if medications are unsuccessful in rate control.

90
Q

what is the most commonly used anti arrhythmic drug for AF in the UK? what should it be taken with and when should it be avoided?

A

felcainide

  • ensure it is taken at the same time as an AV nodal drug (eg. beta blocker or rate limiting CCB) to reduce risk of atrial flutter with 1:1 conduction
  • avoid in patients with coronary artery disease and structural heart disease

flecainide has a pro-arrhythmia risk

91
Q

when should sotalol be avoided?

A

Avoid using in patients with structural heart disease. Can cause QTc prolongation so should measure QTc interval prior to starting and after any dose adjustments.

Sotalol has a pro-arrhythmia risk.

92
Q

what can be used for rhythm control in patients with structural heart disease?

A

amiodarone

93
Q

toxic effect and monitoring in amiodarone?

A

Increased risk of toxic side effects with long term use (e.g., lung fibrosis, thyroid dysfunction, skin photosensitivity, eye complications, liver impairment). Patients will need regular monitoring of LFT/TFT/renal function and lung function. Although an effective drug its side effect profile makes it undesirable to use in the longer term. Can cause QTc prolongation so should measure QTc interval prior to starting and after any dose adjustments. Amiodarone has a pro-arrhythmia risk.

94
Q

what drug is this describing?

Should only be used by Specialists. Less effective than Amiodarone but better side effect profile. Only use in paroxysmal AF and avoid in patients with heart failure or left ventricular impairment.

A

dronedarone

95
Q

what is the only definitive treatment available for AF?

A

catheter ablation. (ie. pulmonary vein isolation)

An invasive procedure usually day-case with local anaesthesia and sedation. A Cryoballoon is placed within the left atrium and the tissue is frozen to -50 degrees for 4 minutes. Each pulmonary vein is treated in sequence. Success rates around 70% in paroxysmal AF and 60% in persistent AF. Radiofrequency ablation can also be used.

96
Q

what is an effective treatment for terminating AF, but doesn’t present it from reccurring?

A

DC cardioversion

It is useful to help assess a patient’s symptoms (i.e., comparing symptoms in AF and normal sinus rhythm) and assess suitability for long term rhythm control. For example, a rhythm control strategy would not be recommended in patients with an unsuccessful DC cardioversion on Amiodarone (defined as no sinus beats following a DC shock after a minimum 4 weeks of Amiodarone)

97
Q

Avoid using bisoprolol and rate limiting calcium channel blocking agents together as there is a high risk of what?

A

AV block

98
Q

what does this show?

A

SVT

The rhythm is a regular narrow complex tachycardia with a ventricular rate of ~180 bpm. There are no clear p waves and the QRS is narrow (less than 120 ms or <3 small squares).

99
Q

what are the 3 causes of SVT?

A

atrioventricular nodal re-entry tachycardia (AVNRT), atrioventricular reciprocating tachycardia (AVRT) or atrial tachycardia

100
Q

what can help distinguish between the different causes of SVT?

A

Blocking the AV node can help to distinguish between the different causes of SVT. Adenosine is a rapidly acting AV nodal blocking agent but avoid in asthma patients.

The Valsalva manoeuvre is a non-pharmacological way of blocking the AV node.

Termination of the tachycardia is consistent with AVNRT or AVRT, whilst unmasking of atrial beats or flutter waves is more consistent with atrial tachycardia and flutter respectively

101
Q

How to differentiate between a ventricular ectopic and supraventricular ectopic?

A

ventricular ectopics are broad whilst supraventricular ectopics are narrow

102
Q

what does this ecg show?

A

Sinus tachycardia with a single premature ventricular ectopic/complex (PVC).

The rhythm is sinus as there are clear normal p waves preceding each QRS beat (aside from the ventricular ectopic) and the PR interval is normal (120-200 ms or between 3-5 small squares). The ventricular rate is about 150 bpm. When counting from left to right beat 7 is broad (i.e., >120 ms or > 3 small squares) and different to the sinus rhythm complexes. It is occurring slightly prematurely. The last 4 beats are sinus rhythm.

103
Q

what is monomorphic VT commonly due to?

A

re-entry circuits within scar in patients with structural heart disease

104
Q

what does this mean

A

idk

105
Q
A

digoxin and warfarin

A patient with AF of longer than 48 h duration is at risk of thromboembolism after cardioversion. Unless the patient is severely compromised, it is standard practice to prescribe anticoagulation to the patient with warfarin for a month before attempting elective cardioversion. During that time the ventricular rate is controlled by prescribing digoxin.

106
Q
A

DC shock and heparin

In this case immediate DC shock is indicated because the patient is severely compromised. The administration of heparin decreases but does not abolish the risk of thromboembolism after cardioversion.

107
Q
A

do not prescribe anything

Her CHADSVASC score is 1 due to her being female. With no other risk factors, NICE recommend not to issue any form of anticoagulation. A male with a score of 1 should be considered for anticoagulation. For AF, treatment would be lifelong, if started, in anyone with a score of 2 or above.

108
Q
A

class 3

Amiodarone has class I, II, III and IV actions but is used clinically for its class III actions. Class III drugs act as a potassium blocker, which prolong the plateau phase of the cardiac action potential and increase the absolute refractory period. As a consequence, they also prolong the Q–T interval.

Amiodarone is the drug of choice to treat VT. When it is used chronically it has a number of adverse effects but these are not an issue in the acute scenario. These adverse effects include bradycardia, pulmonary fibrosis, hepatic fibrosis, corneal microdeposits (regress if drug is stopped), photosensitive rash and thyroid dysfunction.

109
Q
A

Torsades de Pointes

This is torsades de points, which will often degenerate to ventricular fibrillation leading to cardiac arrest. Causes include drugs, electrolyte disturbance and congenital long Q–T syndrome. Conventional anti-arrhythmic will make this condition worse. The treatment of choice is intravenous magnesium sulphate and ventricular pacing at a high rate.

110
Q

SMITH mnemonic for AF causes

A

S – Sepsis
M – Mitral valve pathology (stenosis or regurgitation)
I – Ischaemic heart disease
T – Thyrotoxicosis
H – Hypertension

also remember about alcohol and caffeine

111
Q

what may patients with AF present with?

A
  • palpitations
  • SOB
  • dizziness or syncope (loss of consciousness)
  • symptoms of associated conditions eg. stroke, sepsis or thyrotoxicosis
112
Q

what are the 2 differentials for an irregularly irregular pulse?

A

AF and ventricular ectopics

Ventricular ectopics disappear when the heart rate gets above a certain threshold. Therefore, a regular heart rate during exercise suggests a diagnosis of ventricular ectopics.

113
Q

Paroxysmal atrial fibrillation refers to episodes of atrial fibrillation that reoccur and spontaneously resolve back to sinus rhythm. These episodes can last between 30 seconds and 48 hours.

Patients with a normal ECG and suspected paroxysmal atrial fibrillation can have further investigations with what 2 things?

A
  • 24 hour ambulatory ECG (Holter monitor)
  • cardiac event recorder lasting 1-2 weeks
114
Q

what is valvular AF?

A

AF with significant mitral stenosis or a mechanical heart valve

115
Q

who may be offered rhythm control treatment for AF?

A

patients with:

  • a reversible cause for their AF
  • new onset AF (within the last 48 hours)
  • heart failure caused by AF
  • symptoms despite being effectively rate controlled
116
Q

what are the 2 methods of rhythm control?

A
  • cardioversion
  • long term rhythm control using medications
117
Q

what are the 2 types of cardioversion?

A

immediate and delayed

118
Q

when are the 2 types of cardioversion used?

A

immediate — if AF is either:
- present for less than 48 hours
- causing life-threatening haemodynamic instability

delayed — if the AF
- has been present for 48 hours
- and they are stable

119
Q

what are the 2 options for immediate cardioversion?

A
  • pharmacological (flecainide or amiodarone)
  • electrical
120
Q

what is the drug of choice in pharmacological cardioversion in patients with structural heart disease?

A

amiodarone

121
Q

The patient should be ___________ for at least __ weeks before delayed cardioversion. During the 48 hours before cardioversion, they may have developed a blood clot in the atria, and reverting them to sinus rhythm carries a high risk of mobilising that clot, causing a stroke. They are ___ controlled whilst waiting for cardioversion.

A
  • anticoagulated
  • 3
  • rate
122
Q

what is the target INR for AF?

A

2-3

123
Q

what is the half life of warfarin?

A

1-3 days

124
Q

what does the CHA2DS2VASc score stand for? 0-2 points?

A

C – Congestive heart failure
H – Hypertension
A2 – Age above 75 (scores 2)
D – Diabetes
S2 – Stroke or TIA previously (scores 2)
V – Vascular disease
A – Age 65 – 74
S – Sex (female)

NICE (2021) recommends, based on the CHA2DS2-VASc score:

0 – no anticoagulation
1 – consider anticoagulation in men (women automatically score 1)
2 or more – offer anticoagulation

125
Q

describe the ORBIT score

A

The NICE guidelines recommend using the ORBIT score for assessing the risk of major bleeding in patients with atrial fibrillation taking anticoagulation. The easiest way to calculate the ORBIT score is using an online calculator. The “ORBIT” mnemonic can be used to remember the 5 factors:

O – Older age (age 75 or above)
R – Renal impairment (GFR less than 60)
B – Bleeding previously (history of gastrointestinal or intracranial bleeding)
I – Iron (low haemoglobin or haematocrit)
T – Taking antiplatelet medication

For most patients with atrial fibrillation, the risk of stroke with no anticoagulation will outweigh the risk of bleeding on anticoagulation.

YEAR 3 TCD (15 decks)

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