Cardiac Conduction - Arrhythmias Flashcards by David Houghton

Which cells are autorythmic in the heart?

1 - smooth muscle cells
2 - myocytes
3 - pacemaker cells
4 - all of the above

3 - pacemaker cells

make up 1% of cell in the heart
SA and AV node are the located in the heart

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The action potential that leaves the SA node does what to the heart?

1 - contraction of the ventricles
2 - contraction of the atrium
3 - contraction of the atrium and ventricles

2 - contraction of the atrium

action potential reaches AV and slows down

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The AV node is the only point that allows the action potential to move from the atria to the ventricles, and there is a delay from when the AV receives the node to when it moves into the ventricles. Why is this?

1 - diameter of AV node is small so increases resistance to electrical flow
2 - slower Ca2+ ion channels are used
3 - allows adequate time for ventricles to fill
4 - all of the above

4 - all of the above

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Organise the following into the correct order for conduction through the heart?

1 - AV node
2 - purkinje fibres
3 - SA node
4 - bundle branches

3 - SA node
1 - AV node
4 - bundle branches
2 - purkinje fibres

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The right bundle branch has 1 branch called a fascicle. How many does the left bundle branch have?

1 - 4
2 - 3
3 - 2
4 - 1

3 - 2

anterior fascicle supplies anterior part of LV
posterior fascicle supplies posterior part of LV

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Do the bundle branches or purkinje fibres conduct action potentials faster?

purkinje fibres
this ensures heart contracts in a coordinated fashion

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Are the pacemaker cells in the SA node the only method for initiating the heart to contract?

no
plan A = SA node
plan B = pacemaker cells in atrium
plan C = AV node
plan D = pacemaker cells in bundle branches

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The heart has a number of fail safes incase anything should happen to the SA node. Other parts of the heart are able to initiate a heart beat. The additional places that can generate a heart beat are:

plan B = pacemaker cells in atrium
plan C = AV node
plan D = pacemaker cells in bundle branches

These areas can initiate a heart beat, but the rate would be different. Match up the new rates below with the additional locations above: 30, 40 and 60 bpm.

pacemaker cells in atrium = 60bpm
AV node = 40bpm
pacemaker cells in bundle branches = 30bpm
the above is all relative to the SA node initiating 70bpm

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The pacemaker cells have automaticity to generate the heart beats. However, if any of the 4 points that can generate a heart beats go into dysfunctional automaticity they can create what?

1 - heart failure
2 - left ventricular hypertrophy
3 - arrhythmias
4 - cor pulmonael

3 - arrhythmias

for example if SN become dysfunctional, this may cause sinus tachycardia

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What does tachyarrhythmias mean?

1 - normal heart rhythm
2 - fast heart rhythm abnormality
3 - slow heart rhythm abnormality
4 - all of the above

2 - fast heart rhythm abnormality

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In the ECG below we can see an abnormal heart beat than makes up aprox 1/3 of clinic visits. What is this called and where is it originating from?

1 - ventricular ectopic beats
2 - SA ectopic beats
3 - AV ectopic beats
4 - atrial ectopic beats

1 - ventricular ectopic beats
- originating in ventricles so wide QRS
- QRS is wide here as the normal conduction pathway which is fast (narrow QRS) is not being used

width of QRS
wide = ventricle
narrow = atrial

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In the ECG below we can see an abnormal heart beat than makes up aprox 1/3 of clinic visits. What is this called and where is it originating from?

1 - ventricular ectopic beats
2 - SA ectopic beats
3 - AV ectopic beats
4 - atrial ectopic beats

4 - atrial ectopic beats

width of QRS
narrow = originates in atrium
wide = originates in ventricle
Ventricles here are why as the conduction doesn’t take the normal fast pathway, instead it takes a slower pathway and therefore has a wide QRS

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Are ectopic beats, where people describing the feeling of missing a heart beat dangerous?

no
can have up to 500/day

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In the image attached (A and B) there appears to be a missed beat, what is this?

1 - no heart beat stimulated
2 - heart beat too fast to contract properly
3 - heart is empty and pumps very little blood
4 - can be all of the above

3 - heart is empty and pumps very little blood

the following beat will be overly forceful, so can scare patients and feel like palpitations

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Ectopic beats are generally benign, providing the patient doesn’t have any underlying heart disease. However, if the ectopic beats make up over a specific % then this can lead to ectopic induced cardiomyopathy. What % of total heart beats need to be ectopic for this to occur?

1 - >1%
2 - >5%
3 - >10%
4 - >25%

3 - >10%

R on T wave ectopic, these are also dangerous and can induce VT

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Which of the following must be performed as the basic principles of any potential arrhythmia?

1 - Document the arrhythmia on an ECG 12 lead, ambulatory monitor
2 - Exclude/identify any underlying pathology, IHD, Cardiomyopathy, valve disease, IHD, channelopathies
3 - Exclude electrolyte (low K+) disturbance, thyrotoxicosis
4 - Assess risk, eg Ectopics vs ventricular tachycardia
5 - Lifestyle
6 - Drug treatment
7 - Ablation or Device therapy (if drugs fail)
8 - all of the above

8 - all of the above

manage the patient NOT the ECG

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What is the 1st step in managing a patient with ectopic beats?

1 - exclude underlying heart disease
2 - monitor ECG (24h)
3 - evaluateV frequency of ectopic beats
4 - lifestyle changes

1 - exclude underlying heart disease

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What is the 2nd step in managing a patient with ectopic beats?

1 - exclude underlying heart disease
2 - monitor ECG (24h)
3 - provide drugs
4 - lifestyle changes

2 - monitor ECG (24h)
- helps evaluate frequency of ectopic beats and rule out history of heart disease

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What is the 3rd step in managing a patient with ectopic beats?

1 - exclude underlying heart disease
2 - monitor ECG (24h)
3 - provide drugs
4 - lifestyle changes

4 - lifestyle changes

stop caffeine and alcohol
stop elicit drugs
stop over the count cold (sympathetic) and anti-histamines (parasympathetic)

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In a patient with no known heart disease who is experiencing ectopic beats, should we prescribe medications?

typically no
can increase side effects

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Typically we do not prescribe medications to patients presenting with arrhythmias. But if we need to, which class of drugs would we typically prescribe?

1 - Ca2+ channel blockers
2 - Na+ channel blockers
3 - B-blockers
4 - K+ channel blockers

3 - B-blockers

low dose of propranolol taken as required
low dose Bisoprolol taken

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In addition to ectopic beats inducing abnormal arrhythmias, we have re-entry arrhythmias. This can be due to scar tissue from a previous MI. Is the heart able to send a signal around the scar tissue at the same speed?

yes
but generally there are 2 paths
1 path has fast conduction and 1 path has slow conduction

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Typically if there is a lesion in cardiac tissue, such as following an MI, there will be a fast and a slow conduction around the scar tissue. Generally the fast route dominates and the patient is fine. What happens if you have an ectopic beat occur along the fast pathway?

1 - nothing slow conduction takes over and all is ok
2 - slow pathway takes over fast pathway creating a re-entry circuit
3 - fast pathway catches up and takes over

2 - slow pathway takes over fast pathway creating a re-entry circuit

can create a regular heart beat
BUT can also cause a re-entry tachycardia

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If you have a re-entry at the AV node (called functional micro reentry), this can cause what?

1 - ectopic beats
2 - ventricular fibrillation
3 - supraventricular tachycardia
4 - atrial flutter

3 - supraventricular tachycardia

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Which of the following are ECG characteristics of supraventricular tachycardia? 1 - tachycardia (160-220 bpm) 2 - narrow QRS <120 ms (3 little squares) 3 - regular tachycardia 4 - all of the above

4 - all of the above

Supraventricular tachycardia can be caused by which of the following? 1 - AV nodal reentry tachycardia (AVNRT) 2 - Paroxysmal atrial tachycardia (AT) 3 - Atrio-ventricular reentry tachycardia (AVRT) 4 - all of the above

4 - all of the above - AVNRT = p wave buried in QRS complex as atria and ventricle activated at the same time - AT = p wave before QRS - AVRT - p wave after QRS

There is also the case where some patients such as in wolf parkinsons white syndrome called functional macro re-entry. What can happen here? 1 - accentuates the link between the SA node and AV node 2 - accentuates the signal from the AV node to the ventricles 3 - accessory pathway in addition to AV node connecting the atrium and ventricles 4 - all of the above

3 - accessory pathway in addition to AV node connecting the atrium and ventricles - if ectopic beat occurs at wrong time then this can cause a re-entry circuit between atrium and ventricles

Which of the following are characteristics of an ECG in a patient with wolf parkinsons white syndrome? 1 - short PR interval (<120ms or 0.120) 2 - delta wave - slurred upstroke of QRS complex in R wave) 3 - wide QRS (>120ms) 4 - all of the above

4 - all of the above

In Wolf parkinsons white syndrome, which is caused by an accessory pathway in addition to AV node connecting the atrium and ventricles (see picture). Typically this moves to the atrium and then the ventricles and back along the accessory pathway. However, this can also move down the accessory pathway and back up the AV node. If this occurs which of the following occurs on an ECG trace? 1 - short PR interval (<120ms or 0.120) 2 - delta wave - slurred upstroke of QRS complex in R wave and slurred downstroke of QRS complex in S wave 3 - broad QRS complex (>120ms) 4 - all of the above

1 - broad QRS complex - ventricles are activated abnormally - resembles ventricular tachycardia

What is the 1st step of Supraventricular tachycardia management? 1 - medication 2 - lifestyle changes 3 - rule of cardiac disease 4 - ablation or device therapy

3 - rule of cardiac disease - uncommon for wolf parkinsons white syndrome patients to have cardiac disease - atrial tachycardia patients are likely to have underlying cardiac disease

What is the 2nd step of Supraventricular tachycardia management? 1 - medication 2 - lifestyle changes 3 - rule of cardiac disease 4 - ablation or device therapy

2 - lifestyle changes - stop caffeine and alcohol - stop elicit drugs - stop over the count cold (sympathetic) and anti-histamines (parasympathetic)

If a patient presents with a supraventricular tachycardia we need to get them out of this as quickly as possible. Which 2 of the following can we use to treat this? 1 - shock therapy 2 - vagotonic manoeuvers 3 - tilt testing 4 - AV node blocker medication

2 - vagotonic manoeuvers - carotid massage and valsalva manoeuvre - these slow AV node and may interrupt the arrhythmia - works in 1 in 5 patients 4 - AV node blocker medication

Prior to performing vagotonic manoeuvres, aimed at slowing the AV node, what must you do? 1 - lie the patient down 2 - auscultate carotid artery for bruit 3 - auscultate the aortic valve 4 - percuss the carotid artery

2 - auscultate carotid artery for bruit - need to identify if they have carotid disease - if carotid disease is present you could cause embolisation and strokes

If a patient presents with a supraventricular tachycardia we need to get them out of this as quickly as possible. We can use vagotonic manoeuvres (aimed at slowing the AV node) and AV node blocker medication. Which 2 of the following medications would be used for this? 1 - Atenolol 2 - Amiodarone 3 - Verapamil 4 - Adenosine

3 - Verapamil - Ca2+ channel blocker - Calcium channels are the major drivers of depolarisation in the pacemaker cells of the AV and AS node node. 4 - Adenosine - opens ACh sensitive K+ channels and blocks Ca+ influx in the atrium and nodal tissues.

To prevent a supraventricular tachycardia we need to get them out of this as quickly as possible. Which of the following drugs would NOT be used here? 1 - Flecainide 2 - Bisoprolol 3 - Amiodarone 4 - Verapamil

3 - Amiodarone Atrial tachycardia: atrial stabiliser = Bisoprolol AV nodal reentry: AV node blocker = Bisoprolol, Verapamil) WPW – accessory pathway blocker = Flecainide)

Electrophysiological studyand Ablation is a method where multiple pacing wires are passed into the heart (RA, RV, bundle of HIS and coronary sinus). This allows a programmed electrical stimulation to provoke arrhythmias, allowing mapping of the arrhythmia. What is the purpose of this approach? 1 - identify the arrhythmia and then burn local tissue, creating scar 2 - identify the arrhythmia and then give drugs 3 - identify the arrhythmia and then give lifestyle advice 4 - all of the above

1 - identify the arrhythmia and then burn local tissue, creating scar - aim is to interrupt the re-entry circuit - 90% effective and treatment of choice in younger patients

The most common tachycardia is sinus tachycardia. Which of the following can cause sinus tachycardia? 1 - reactive response 2 - thyrotoxicosis 3 - severe anaemia 4 - pulmonary embolism 5 - intrinsic sinus node dysfunction (rare) 6 - all of the above

6 - all of the above - reactive response = Fever, Pain, Emotional stress / anxiety, Dehydration, Stimulant drugs and Low BP - essentially a stress response

There are some serious arrhythmias, which is the most common serious arrhythmia? 1 - atrial flutter 2 - supraventricular tachycardia 3 - ventricular tachycardia 4 - atrial fibrillation

4 - atrial fibrillation - if ventricular fibrillation was an option this would be the most dangerous - 2.5% prevalence in the UK

Is atrial fibrillation caused by multiple functional micro or macro re-entry? - micro-reentry = a small area of cardiac tissue is involved - macro-reentru = a large area of cardiac tissue is involved

- macro re-entry - multiple of these in the atria - causes rapid and irregular atrial contractions that send this signal to the ventricles

Which of the following underlying structural heart diseases is atrial fibrillation common in? 1 - IHD 2 - cardiomyopathies 3 - valvular disease (mitral with LA dilation) 4 - all of the above

4 - all of the above

Which of the following conditions is atrial fibrillation common in? 1 - Hyperthryoidism 2 - Hypertension 3 - Obesity 4 - Pbstructive sleep apnoea 5 - all of the above

5 - all of the above - hypertension is most common cause

What is the diagnosis in the ECG? 1 - RBBB 2 - NSTEMI 3 - AF 4 - atrial flutter

3 - AF - rhythm is irregular is the giveaway

Which of the following is NOT a key characteristic on an ECG in a patient with atrial fibrillation? 1 - irregular RR intervals 2 - regular sinus rhythm 3 - no clear P waves 4 - no 2 QRS complexes are the same

2 - regular sinus rhythm

Which of the following are typical symptoms that patients present with in AF? 1 - palpitations 2 - breathlessness 3 - dizziness 4 - fatigue 5 - all of the above

5 - all of the above - symptoms and rhythm can be intermittent or persistent

Which of the following are common medical events where AF can be present? 1 - MI 2 - sepsis 3 - Thyrotoxicosis 4 - post cardiac surgery (3rd will have) 5 - all of the above

5 - all of the above

Which serious condition can AF be found in incidentally? 1 - hepatomegaly 2 - CKD 3 - DVT 4 - stroke

4 - stroke - AF causes blood clots, so following a stroke it can be found during investigations

Practical management of AF is complex. Organised the following steps in the correct order: 1 - Strategy, Rate control, or Maintenance of sinus rhythm (rhythm control). 2 - Classification, paroxysmal, persistent or permanent 3 - Risk of thrombo-embolism Thrombus from LA appendage Cause of 10% acute strokes 4 - identify if underlying pathology: Structural heart disease or IHD Non-cardiac problem

2 - Classification, paroxysmal, persistent or permanent 4 - identify if underlying pathology: Structural heart disease or IHD Non-cardiac problem 3 - Risk of thrombo-embolism Thrombus from LA appendage Cause of c.10% od acute strokes 1 - Strategy, Rate control, or maintenance of sinus rhythm (rhythm control).

The thromboembolic risk is high if a patient has a significant structural heart disease (mitral stenosis) or a high score using which scoring tool? 1 - CHADS-VASC score 2 - CURB score 3 - Q-risk score 4 - Modified Glasgow scale

1 - CHADS-VASC score

Which of the following tests would NOT typically be done as an investigation in someone with suspected AF? 1 - alcohol and drug history 2 - TFTs 3 - FBC (High MCV) 4 - LFTs (high GGT) 5 - CT of chest and head 6 - Chest X-ray +/- lung function tests 7 - Echocardiogram (valve disease and cardiomyopathy) 8 - screen for IHD

5 - CT of chest and head

In additional to the typical lifestyle changes, we can used medication in AF. Which 3 of the following medications are used in paroxysmal AF in an attempt to maintain sinus rhythm? 1 - Flecainide 2 - Atenolol 3 - Amiodarone 4 - Dronedarone 5 - Verapamil 6 - Bisoprolol

1 - Flecainide (Na+ channel blocker) 3 - Amiodarone (K+ channel blocker) 6 - Bisoprolol (B-blocker) - Amiodarone is most effective 60% effective at maintaining sinus rhythm at 1 year - inhibits K+ channels and slows the heart down as it cannot depolarise - BUT Flecainide and Bisoprolol preferred due to lower toxicity - both of these slow conduction through the SA and AV node, with the hope to correct the fast AF

Electrophysiological studyand Ablation therapy is now the commonest indication for AF. Is it effective at returning sinus rhythm to normal?

- no - only used when other treatment has failed - only 1/3 of patients are cured - anticoagulants are also recommended

In elderly patients with AF, how are they managed? 1 - medications only 2 - ablation 3 - pace maker 4 - pace maker then ablation

4 - pace maker then ablation - stops heart going slow, then correct the rhythm

If a patient has persistent AF that does not correct itself spontaneously, what treatment can be provided? 1 - cardioversion 2 - repeated ablation therapy 3 - permanent pacemaker 4 - Ca2+ and K+ channel blocker

1 - cardioversion - depolarises all cells in the heart - resets the heart - will need atrial stabilising drug following

In patients with permanent AF that has not responded to any treatments the aim is a HR of <110bpm. What of the following is not typically used in an attempt to do this? 1 - Bisoprolol 2 - verapamil or diltiazem 3 - amiodarone 4 - digoxin 5 - amlodipine

5 - amlodipine - Ca2+ channel blocker that predominantly affects the blood vessels - all other drugs block the AV node - may give bisoprolol + amiodarone or digoxin, BUT not more than 2 drugs

In atrial flutter is there multiple or a single macro re-entry circuit?

- single macro re-entry circuit - commonly moves anti-clockwise around the atrium and through the cavo-tricuspid isthmus

In atrial flutter what is the typical circuit speed? 1 - 300 bpm 2 - 150 bpm 3 - 75 bpm 4 - 60 bpm

1 - 300 bpm - BUT not all are conducted into contractions

In atrial flutter the typical re-entry circuit speed is 300 bpm, BUT not all of these are conducted into heart contractions. Match the following HR (300, 150 and 75 bpm) for each of the following conduction ratios? 1 - 4:1 conduction 2 - 2:1 conduction 3 - 1:1 conduction - essentially this means for every 4 re-entry circuits around the atrium, 1 is turned into a contraction of the heart (4:1)

1 - 4:1 conduction = 75 bpm 2 - 2:1 conduction = 150 bpm 3 - 1:1 conduction = 300 bpm - typically gives a saw tooth appearance on nan ECG

What is the most likely diagnosis according to the ECG? 1 - RBBB 2 - VT 3 - VF 4 - AF

3 - VF - chaotic ECG - no discernible complexes - very dangerous arrhythmia

If we see a broad complex tachycardia, what should out 1st diagnosis be? 1 - ventricular tachycardia 2 - atrial flutter 3 - AF 4 - RBBB

1 - ventricular tachycardia

Which of the following are key characteristics of ventricular tachycardia on an ECG? 1 - broad QRS complex (>140ms) 2 - regular QRS complexes 3 - >100 bpm 4 - all of the above

4 - all of the above - no contraction from the atria, so abnormal conduction pathways which are slower are used. Therefore QRS complexes appear wider

Ventricular tachycardia can be monomorphic or polymorphic. What is the difference between the 2? 1 - appearance of QRS complexes 2 - presence of RBBB 3 - HR > 200 bpm 4 - underlying IHD

1 - appearance of QRS complexes - monomorphic = all QRS complexes are the same - polymorphic = multiple different QRS complexes

Which of the following are key features associated with monophasic VT? 1 - Regular QRST complex look the same 2 - Acute MI 3 - LV scarring (eg previous MI, myocarditis) 4 - Cardiomyopathies (dilated, hypertrophic) 5 - all of the above

5 - all of the above

Which of the following are key features associated with polyphasic VT, such as Torsade de Pointes? 1 - Irregular and the QRST complexes vary 2 - Channelopathy (eg long QT syndromes) 3 - Drug toxicity (eg drug-induced long QT) 4 - Acute MI 5 - all of the above

5 - all of the above - key difference between Torsade de Pointes and VT, is that VT are regular QRS

Is ventricular tachycardia dangerous?

- yes - can develop into VF

Ventricular tachycardia is very dangerous as it can develop into VF and be potentially life threatening. It therefore needs to be corrected asap. Which drug is used to do this? 1 - Flecainide 2 - Atenolol 3 - Amiodarone 4 - Verapamil

3 - Amiodarone - K+ channel blocker - K+ channel controls repolarisation, so if this is blocked the heart cannot depolarise as quickly and everything is slowed down - aim is to slow repolarisation and slow down and correct arrhythmias - if this fails, give emergency direct current cardioversion

If we manage to correct a patients VT, which 2 electrolytes do we need to give them? 1 - Na+ 2 - K+ 3 - Mg+ 4 - Ca2+

2 - K+ - >4.5 mmol/L - typically use amiodarone (K+ channel blocker) to reset VT 3 - Mg+ - even if normal

If we manage to correct a patients VT, which of the following investigations would we then do? 1 - 12 lead ECG 2 - echocardiogram 3 - angiogram and revascularise 4 - all of the above

4 - all of the above - all aimed at looking for and treating underlying heart disease

If we manage to correct a patients VT, we want to try a ventricular stabilising drug. Which of the following is NOT one of these drugs? 1 - Lignocaine 2 - Bisoprolol 3 - Amiodarone 4 - Verapamil

4 - Verapamil

In a patient with an inherited prolonged QT interval, which medication has been shown to be affective at treating this? 1 - Lignocaine 2 - Bisoprolol 3 - Amiodarone 4 - Verapami

2 - Bisoprolol - beta blocker

Low levels of which 2 electrolytes can cause prolonged QT intervals? 1 - Na+ 2 - K+ 3 - Mg+ 4 - Ca2+

2 - K+ - involved in repolarisation 3 - Mg+ - low Mg+ inhibits Na+/K+ ATPase, this reducing K+ and prolonging repolarisation

Which 2 of the following drugs can cause a QT prolongation? 1 - Lignocaine 2 - Bisoprolol 3 - Amiodarone 4 - Flecainide

3 - Amiodarone - K+ channel blocker, delays repolarisation and prolongs QT interval 4 - Flecainide - has an inhibitory effect on K+ channels, so can delay repolarisation

Which fruit has been shown to prolong QT intervals? 1 - grapefruit 2 - banana 3 - pineapple 4 - kiwi

1 - grapefruit - affects cytochrome P450 and can block K+ channels

Which of the following are causes of bradycardia? 1 - Sinus node dysfunction 2 - AV node block 3 - Bundle branch dysfunction 4 - all of the above

4 - all of the above

In sinus node dysfunction, the AV node can take over. How can we tell this on an ECG? 1 - prolonged PR interval 2 - up-sloping of QRS complex 3 - absence of P waves 4 - U waves

3 - absence of P waves - bradycardia is also very likely

The ventricular septum depolarises from right to left. If there is a block on the left bundle, does the ventricular septum still depolarises from right to left?

- no - depolarises from left to right

In a left bundle branch block we might see an M and W shape in which 2 leads? 1 - M in V1 and W in V6 2 - M in V3 and W in V1 3 - W in V1 and M in V6 4 - W in V1 and M in V3

3 - W in V1 and M in V6 - remembered as WilliaM

Which of the following are typical features of a left bundle branch block on an ECG? 1 - Wide QRS complexes (>3 small squares) 2 - QRS complexes mostly below baseline in V1 3 - Lateral ST depression and T wave inversion 4 - M shaped QRS complex in lead V6 5 - W shaped QRS complex in lead V1 6 - all of the above

6 - all of the above

Which of the following is NOT a common cause of RBBB? 1 - IHD (anterior MI) 2 - Hypertensive heart disease 3 - PE 4 - Cardiomyopathy (eg dilated, hypertrophic)

3 - PE - can cause RBBB

The ventricular septum depolarises from right to left. If the is a block on the right bundle, does the ventricular septum still depolarises from right to left?

- no - depolarised from left to right

In a right bundle branch block we might see an M and W shape in which 2 leads? 1 - M in V1 and W in V6 2 - M in V3 and W in V1 3 - W in V1 and M in V6 4 - W in V1 and M in V3

1 - M in V1 and W in V6 - remembered as MorroW

Which of the following are typical features of a right bundle branch block on an ECG? 1 - Wide QRS complexes (>3 small squares) 2 - Complex mostly above the baseline in V1 3 - rSR’ pattern in V1-2 4 - Deep slurred S wave in lateral leads 5 - all of the above

5 - all of the above

RBBB can be normal with up to 10% of the population having RBBB. Which of the following is NOT a cause RBBB 1 - Chronic lung disease 2 - Hypertensive heart disease 3 - Pulmonary hypertension 4 - PE 5 - Congenital heart disease (ventricular septal defect) 6 - IHD, eg prior anterior MI

2 - Hypertensive heart disease

In normal physiology there is a delay between the conduction from the SA (atrium contract) and AV node (ventricles contract), which allows the atrium to pump blood into the ventricles. In a first degree heart block this delay between the SA and AV node is prolonged. How does this appear on an ECG? 1 - no P wave 2 - prolonged PR interval 3 - broadened QRS complex 4 - shorted PR interval

2 - prolonged PR interval - PR interval >300ms (8 small squares) - normal PR interval = 120-200 ms (3-5 small squares)

1st degree heart block is a prolonged period between the SA ands AV node (>200ms). What happens in a Wenckebach (Mobitz type 1) 2nd degree AV block? 1 - PR interval is reduced 2 - QRS is absent 3 -PR interval gets longer each beat, until eventually it misses a beat 4 - T waves invert

3 -PR interval gets longer each beat, until eventually it misses a beat - can also see a narrow QRS complex as the escape rhythm is coming from the AV node - this is common following a MI

1st degree heart block is a prolonged period between the SA ands AV node (>200ms). What happens in Mobitz type 2 2nd degree AV block? 1 - PR interval is increased progressively 2 - QRS is absent 3 -PR is normal, but then misses a beat 4 - T waves invert

3 -PR is normal, but then misses a beat - block is below the AV node

What is a bi-fasicular block? 1 - 1 of the 3 fascicles is blocked 2 - 2 of the 3 fascicles are blocked 3 - all of the 3 fascicles are blocked 4 - complete bundle branch blocked

2 - 2 of the 3 fasicicles are blocked - bi = 2 - normally accompanied by RBBB or LBBB

What is 3rd degree complete AV block? 1 - SA and AV nodes do not work 2 - SA and AV nodes fire at the same time 3 - ventricles only are contracting 4 - atrium and ventricles are contracting independently from one another

4 - atrium and ventricles are contracting independently from one another - called AV dissociation

3rd degree complete AV block is when the atrium and ventricles are contracting independently from one another, called AV dissociation. Is this dangerous?

- yes - significantly reduces cardiac output - can cause sudden cardiac death

Which of the following are symptoms of a patient with bradycardia who may have some degree of heart block? 1 - asymptomatic 2 - syncope/dizziness 3 - fatigue 4 - breathlessness 5 - shock 6 - death 7 - all of the above

7 - all of the above

Do patients who are bradycardic, but asymptomatic with a low grade heart block, do they require treatment?

- generally no - reassurance and monitoring - no adverse mortality

If a patient presents acutely with bradycardia what medication can be prescribed? 1 - Atropine 2 - Adrenaline 3 - Lithium 4 - Pabrinex

1 - Atropine - Anticholinergics (antimuscarinics) so decreases para-sympathetic activity - would speed up the AV node

If a patient presents chronically and the escape conduction is coming from the ventricles, medications don't typically work. What else can be used instead? 1 - direct current cardioversion 2 - pacemaker 3 - ablation 4 - angiogram

2 - pacemaker

Which of the following drugs typically can cause bradycardia? 1 - Bisoprolol 2 - Verapamil/Diltiazem 3 - Amiodarone 4 - Digoxin 5 - all of the above

5 - all of the above - drugs are the most common cause of bradycardia

Which 2 of the following conditions can cause bradycardia? 1 - hypertension 2 - MI 3 - hypothyroidism 4 - CKD

2 - MI 3 - hypothyroidism

Based on prognostic grounds, which patients of the following would receive a permanent pacemaker? 1 - complete heart block 3rd degree heart block) 2 - Mobitz type 2 block 3 - alternating LBBB to RBBB 4 - all of the above

4 - all of the above

What do very large spikes on an ECG signify? 1 - LVH 2 - LBBB 3 - ectopic beats 4 - pacemaker

4 - pacemaker - normally placed on the right ventricle as this reduces the risk of blood clots, but if they form they are removed in the lungs

Pacemaker syndrome is caused by what? 1 - ventricles contract before atrium 2 - atrium contract before ventricles 3 - atrium and ventricles contract together 4. -all of the above

3 - atrium and ventricles contract together - caused by suboptimal atrioventricular synchrony following implantation of pacemaker - atria contract while tricuspid and mitral valves are closed so no blood goes into ventricles

Which of the following are caused by pacemaker syndrome where there is suboptimal atrioventricular synchrony following the implantation of a pacemaker? 1 - syncope 2 - dizzy spells 3 - fatigue 4 - dyspnoea 5 - all of the above

5 - all of the above

When looking at single chamber pacemakers what does the first letter V related to? 1 - ventricle is being paced 2 - ventricle is sensing the pacing 3 - that happens following the sensing

1 - ventricle is being paced - used in AF

When looking at single chamber pacemakers what does the 2nd letter V related to? 1 - ventricle is being paced 2 - ventricle is sensing the pacing 3 - that happens following the sensing

2 - ventricle is sensing the pacing

When looking at single chamber pacemakers what does the 2nd letter I related to? 1 - ventricle is being paced 2 - ventricle is sensing the pacing 3 - that happens following the sensing

3 - that happens following the sensing

When looking at double chamber pacemakers what does the first letter V related to? 1 - chamber being paced 2 - chamber being sensed 3 - what happens following sensed, so triggering the response

1 - chamber being paced

When looking at double chamber pacemakers what does the first letter A related to? 1 - chamber being paced 2 - chamber being sensed 3 - what happens following sensed, so triggering the response

2 - chamber being sensed

When looking at double chamber pacemakers what does the first letter T related to? 1 - chamber being paced 2 - chamber being sensed 3 - what happens following sensed, so triggering the response

3 - what happens following sensed, so triggering the response

In a modern dual chamber pacemaker that can pace the atrium and ventricle, sense the atrium and ventricle and can inhibit and trigger both the atrium and ventricle, this is called a dual chamber pacemaker. 1 - 1st D = pace the chambers 2 - 2nd D = sense the chambers 3 - 3rd D = inhibit or trigger the chambers 4 - R = rate, where pacemaker increases HR during activity/exercise

In a patient with a pulmonary embolism, what is the standard ECG tracing? 1 - ST elevation 2 - no P wave and prolonged QRS 3 - S1Q3T3 pattern 4 -delta waves

3 - S1Q3T3 pattern - deep S wave in lead I - Q wave in lead III - inverted T wave in III (20%)

Using the ECG image, what is the most likely diagnosis? 1 - RBBB 2 - NSTEMI 3 - AF 4 - atrial flutter

4 - atrial flutter

What is the most common arrhythmia that causes cardiac arrest? 1 - AF 2 - atrial flutter 3 - VT 4 - VF

3 - VT

Cardiac Conduction - Arrhythmias Flashcards

(108 cards)