Arrythmia

Question 1

What is the most common sustained cardiac arrhythmia?

Answer 1

Atrial fibrillation (AF)
 It is very common, being present in around 5% of patients over aged 70-75 years and 10% of patients aged 80-85 years

Question 2

What is the most important important aspect of managing patients with Atrial Fibrillation?

Answer 2

educing the increased risk of stroke which is present in these patients.

Question 3

What can uncontrolled atrial fibrillation can result in?

Answer 3

symptomatic palpitations and inefficient cardiac function

Question 4

What are the types of atrial fibrillation?

Answer 4

first detected episode (irrespective of whether it is symptomatic or self-terminating)
recurrent episodes, when a patient has 2 or more episodes of AF.
in permanent AF there is continuous atrial fibrillation which cannot be cardioverted or if attempts to do so are deemed inappropriate.

Question 5

What are the two types of recurrent atrial fibrillation?

Answer 5

PAROXYSMAL: If episodes of AF terminate spontaneously then the term paroxysmal AF is used. Such episodes last less than 7 days (typically < 24 hours).

PERSISTENT: If the arrhythmia is not self-terminating then the term persistent AF is used. Such episodes usually last greater than 7 days

Question 6

What are the treatment goals of permanent AF?

Answer 6

Treatment goals are therefore rate control and anticoagulation if appropriate

Question 7

What are the Symptoms and signs of AF?

Answer 7

Symptoms
palpitations
dyspnoea
chest pain

Signs
an irregularly irregular pulse

Question 8

What other conditions (other than AF) can give you an irregular pulse?

Answer 8

ventricular ectopics or sinus arrhythmia.

Question 9

What investigation is essential for diagnosis of AF?

Answer 9

ECG

Question 10

What are the two key parts of managing patients with AF?

Answer 10

1. Rate/rhythm control
2. Reducing stroke risk
   rate control: accept that the pulse will be irregular, but slow the rate down to avoid negative effects on cardiac function
   rhythm control: try to get the patient back into, and maintain, normal sinus rhythm. This is termed cardioversion. Drugs (pharmacological cardioversion) and synchronised DC electrical shocks (electrical cardioversion) may be used for this purpose

Question 11

For many years the predominant approach was to try and maintain a patient in sinus rhythm. This approach changed in the early 2000’s and now the majority of patients are managed with a rate control strategy.

Answer 11

tru

Question 12

For AF NICE advocate using a rate control strategy except in a number of specific situations such as?

Answer 12

coexistent heart failure, first onset AF or where there is an obvious reversible cause.
Other patients may have had a rate control strategy initially but switch to rhythm control if symptoms/heart rate fails to settle.

Question 13

What medications are used for rate control in AF?

Answer 13

A beta-blocker or a rate-limiting calcium channel blocker (e.g. diltiazem) is used first-line to control the rate in AF.

If one drug does not control the rate adequately NICE recommend combination therapy with any 2 of the following:
a betablocker
diltiazem
digoxin

Question 14

In cardioversion, the moment a patient switches from AF to sinus rhythm presents the highest risk for embolism leading to stroke.

Answer 14

true

Question 15

Why must patients either have had a short duration of symptoms (less than 48 hours) or be anticoagulated for a period of time prior to attempting cardioversion?

Answer 15

In cardioversion, the moment a patient switches from AF to sinus rhythm presents the highest risk for embolism leading to stroke.

Question 16

How do clinicians identify the most appropriate anticoagulation strategy for reducing stroke risn in AF?

Answer 16

CHA2DS2-VASc

Question 17

What does CHA2DS2VasC consist of?

Answer 17

C	Congestive heart failure	1
H	Hypertension (or treated hypertension) 1
A2	Age >= 75 years 2
Age 65-74 years	1
D	Diabetes	1
S2	Prior Stroke or TIA 2
V	Vascular disease (including ischaemic heart disease and peripheral arterial disease)	1
S	Sex (female)	1

Question 18

What is the suggested anticoagulation strategy based on the CHA2DS2-VASc score?

Answer 18

0 No treatment
1 Males: Consider anticoagulation
Females: No treatment (this is because their score of 1 is only reached due to their gender)
2 or more Offer anticoagulation

Question 19

What is a common contraindication for beta-blockers

Answer 19

asthma

Question 20

For rate control in AF which medication is the preferred choice if the patient has coexistent heart failure?

Answer 20

Digoxin

not considered first-line anymore as they are less effective at controlling the heart rate during exercise

Question 21

What other Agents used to maintain sinus rhythm in patients with a history of atrial fibrillation?

Answer 21

sotalol
amiodarone
flecainide

Question 22

What are the Factors favouring rate control in AF?

Answer 22

Older than 65 years

History of ischaemic heart disease

Question 23

What are the Factors favouring rhythm control in AF?

Answer 23

Younger than 65 years
Symptomatic
First presentation
Lone AF or AF secondary to a corrected precipitant (e.g. Alcohol)
Congestive heart failure

Question 24

NICE recommends the use of catheter ablation for those with AF who?

Answer 24

have not responded to or wish to avoid, antiarrhythmic medication.

Question 25

What are the Technical aspects of Catheter ablation?

Answer 25

the aim is to ablate the faulty electrical pathways that are resulting in atrial fibrillation. This is typically due to aberrant electrical activity between the pulmonary veins and left atrium the procedure is performed percutaneously, typically via the groin both radiofrequency (uses heat generated from medium frequency alternating current) and cryotherapy can be used to ablate the tissue

Question 26

When should anticoagulation be started for patients undergoing catheter ablation for AF?

Answer 26

Anticoagulation should be used 4 weeks before and during the procedure Therefore, patients still require anticoagulation afterwards as per there CHA2DS2-VASc score if score = 0: 2 months anticoagulation recommended if score > 1: longterm anticoagulation recommended

Question 27

What are the complications of catheter ablation?

Answer 27

cardiac tamponade stroke pulmonary valve stenosis

Question 28

What is the success rate of catheter ablation?

Answer 28

around 50% of patients experience an early recurrence (within 3 months) of AF that often resolves spontaneously longer term, after 3 years, around 55% of patients who've had a single procedure remain in sinus rhythm. Of patient who've undergone multiple procedures around 80% are in sinus rhythm

Question 29

When would cardioversion be used in atrial fibrillation?

Answer 29

electrical cardioversion as an emergency if the patient is haemodynamically unstable electrical or pharmacological cardioversion as an elective procedure where a rhythm control strategy is preferred.

Question 30

Electrical cardioversion is synchronised to the R wave to prevent delivery of a shock during the vulnerable period of cardiac repolarisation when ventricular fibrillation can be induced.

Answer 30

true

Question 31

In terms of cardioversion If the atrial fibrillation is definitely of less than 48 hours onset patients should be?

Answer 31

Put on Heparin. Patients who have risk factors for ischaemic stroke should be put on lifelong oral anticoagulation. They may be cardioverted electrically or pharmalogically.

Question 32

Following electrical cardioversion if AF is confirmed as being less than 48 hours duration then further anticoagulation is?

Answer 32

unnecessary

Question 33

If the patient has been in AF for more than 48 hours then anticoagulation should be given when? What is an alternative?

Answer 33

at least 3 weeks prior to cardioversion An alternative strategy is to perform a transoesophageal echo (TOE) to exclude a left atrial appendage (LAA) thrombus. If excluded patients may be heparinised and cardioverted immediately.

Question 34

If onset of AF >48 hours NICE recommend which cardioversion?

Answer 34

electrical

Question 35

What suggests a high risk of cardioversion failure?

Answer 35

Previous failure or AF recurrence

Question 36

If onset of AF >48 hours & If there is a high risk of cardioversion failure then it is reccomended to have what.

Answer 36

4 weeks amiodarone or sotalol prior to electrical cardioversion

Question 37

Following electrical cardioversion if AF is confirmed as being more than 48 hours duration then further anticoagulation is?

Answer 37

Following electrical cardioversion patients should be anticoagulated for at least 4 weeks. After this time decisions about anticoagulation should be taken on an individual basis depending on the risk of recurrence

Question 38

Agents with proven efficacy in the pharmacological cardioversion of atrial fibrillation?

Answer 38

``` amiodarone flecainide (if no structural heart disease) ``` cardioversion' pharmacology - amiodarone if structural heart disease, flecainide or amiodarone in those without structural heart disease

Question 39

Less effective agents in the pharmacological cardioversion of atrial fibrillation?

Answer 39

``` beta-blockers (including sotalol) calcium channel blockers digoxin disopyramide procainamide ```

Question 40

If CHA2DS2-VASc score suggests no need for anticoagulation it is important to ensure what?

Answer 40

transthoracic echocardiogram has been done to exclude valvular heart disease, which in combination with AF is an absolute indication for anticoagulation.

Question 41

NICE recommend that we offer patients a choice of anticoagulation

Answer 41

true | warfarin and the novel oral anticoagulants (NOACs)

Question 42

Aspirin is no longer recommended for reducing stroke risk in patients with AF

Answer 42

true

Question 43

A history of what make us consider whether warfarinisation is in the best interests of the patient?

Answer 43

falls, old age, alcohol excess and a history of previous bleeding

Question 44

NICE now recommend we formalise risk assessment for wararin prescription using what system?

Answer 44

HASBLED

Question 45

There are no formal rules on how we act on the HAS-BLED score

Answer 45

true

Question 46

A HASBLED score of what indicates 'high risk' of bleeding?

Answer 46

>= 3 | defined as intracranial haemorrhage, hospitalisation, haemoglobin decrease >2 g/L, and/or transfusion.

Question 47

Outline HASBLED score

Answer 47

H Hypertension, uncontrolled, systolic BP > 160 mmHg 1 A Abnormal renal function (dialysis or creatinine > 200) Or Abnormal liver function (cirrhosis, bilirubin > 2 times normal, ALT/AST/ALP > 3 times normal 1 for any renal abnormalities 1 for any liver abnormalities S Stroke, history of 1 B Bleeding, history of bleeding or tendency to bleed 1 L Labile INRs (unstable/high INRs, time in therapeutic range < 60%) 1 E Elderly (> 65 years) 1 D Drugs Predisposing to Bleeding (Antiplatelet agents, NSAIDs) Or Alcohol Use (>8 drinks/week) 1 for drugs 1 for alcohol

Question 48

following a stroke or TIA, what should be given as the anticoagulant of choice?

Answer 48

warfarin or a direct thrombin or factor Xa inhibitor (Rivaroxaban, Apixaban) Antiplatelets should only be given if needed for the treatment of other comorbidities

Question 49

In acute stroke patients, in the absence of haemorrhage, anticoagulation therapy should be commenced after?

Answer 49

2 weeks. If imaging shows a very large cerebral infarction then the initiation of anticoagulation should be delayed

Question 50

Atrial flutter is a form of supraventricular tachycardia characterised by?

Answer 50

succession of rapid atrial depolarisation waves.

Question 51

What are the ECG findings in atrial flutter?

Answer 51

'sawtooth' appearance as the underlying atrial rate is often around 300/min the ventricular or heart rate is dependent on the degree of AV block. For example if there is 2:1 block the ventricular rate will be 150/min flutter waves may be visible following carotid sinus massage or adenosine

Question 52

How do you manage atrial flutter?

Answer 52

is similar to that of atrial fibrillation although medication may be less effective atrial flutter is more sensitive to cardioversion however so lower energy levels may be used radiofrequency ablation of the tricuspid valve isthmus is curative for most patients

Question 53

What is Ventricular tachycardia?

Answer 53

broad-complex tachycardia originating from a ventricular ectopic focus. It has the potential to precipitate ventricular fibrillation and hence requires urgent treatment.

Question 54

What are the two main types of VT?

Answer 54

monomorphic VT: most commonly caused by myocardial infarction polymorphic VT: A subtype of polymorphic VT is torsades de pointes which is precipitated by prolongation of the QT interval.

Question 55

What are the congenital causes of prolonged QT interval?

Answer 55

Jervell-Lange-Nielsen syndrome (includes deafness and is due to an abnormal potassium channel) Romano-Ward syndrome (no deafness)

Question 56

What are the drug causes of prolonged QT interval?

Answer 56

``` amiodarone, sotalol, class 1a antiarrhythmic drugs tricyclic antidepressants, fluoxetine chloroquine terfenadine erythromycin ```

Question 57

What are the other causes of prolonged QT interval?

Answer 57

``` electrolyte: hypocalcaemia, hypokalaemia, hypomagnesaemia acute myocardial infarction myocarditis hypothermia subarachnoid haemorrhage ```

Question 58

What are the indications for cardioversion in VT?

Answer 58

If the patient has adverse signs (systolic BP < 90 mmHg, chest pain, heart failure) then immediate cardioversion is indicated. In the absence of such signs antiarrhythmics may be used. If these fail, then electrical cardioversion may be needed with synchronised DC shocks

Question 59

What drug therapy is used in VT?

Answer 59

amiodarone: ideally administered through a central line lidocaine: use with caution in severe left ventricular impairment procainamide

Question 60

Which drug should NOT be used in VT?

Answer 60

Verapamil This is because Verapamil also blocks the calcium current responsible for sinus and AV nodal depolarization and can precipitate haemodynamic detoriaration, VF & cardiac arrest

Question 61

What to do if drug therapy fails in VT?

Answer 61

``` electrophysiological study (EPS) implant able cardioverter-defibrillator (ICD) - this is particularly indicated in patients with significantly impaired LV function ```

Question 62

What is the key step in management of peri-arrest tachycardias?

Answer 62

Following basic ABC assessment, patients are classified as being stable or unstable according to the presence of any adverse signs: shock: hypotension (systolic blood pressure < 90 mmHg), pallor, sweating, cold, clammy extremities, confusion or impaired consciousness syncope myocardial ischaemia heart failure

Question 63

If there are adverse signs present in peri-arrest tachycardias what should be done?

Answer 63

synchronised DC shocks should be given Treatment following this is given according to whether the QRS complex is narrow or broad and whether the rhythm is regular or irregular.

Question 64

How do you treat regular broad-complex tachycardias in the context of peri-arrest?

Answer 64

stable/unstable -> shock? assume ventricular tachycardia (unless previously confirmed SVT with bundle branch block) loading dose of amiodarone followed by 24 hour infusion

Question 65

How do you treat irregular broad-complex tachycardias in the context of peri-arrest?

Answer 65

stable/unstable -> shock? 1. AF with bundle branch block - treat as for narrow complex tachycardia 2. Polymorphic VT (e.g. Torsade de pointes) - IV magnesium

Question 66

How do you treat regular narrow-complex tachycardias in the context of peri-arrest?

Answer 66

stable/unstable -> shock? vagal manoeuvres followed by IV adenosine if above unsuccessful consider diagnosis of atrial flutter and control rate (e.g. Beta-blockers)

Question 67

How do you treat irregular narrow-complex tachycardias in the context of peri-arrest?

Answer 67

stable/unstable -> shock? probable atrial fibrillation if onset < 48 hr consider electrical or chemical cardioversion rate control (e.g. Beta-blocker or digoxin) and anticoagulation

Question 68

What are possible causes of palpitations?

Answer 68

arrhythmias stress increased awareness of normal heart beat / extrasystoles

Question 69

What are first line investigations of palpitations?

Answer 69

12-lead ECG: this will only capture the heart rhythm for a few seconds and hence is likely to miss episodic arrhythmias. However, other abnormalities linked to the underlying arrhythmia (for example a prolonged QT interval or PR interval, or changes suggesting recent myocardial ischaemia) may be seen. thyroid function tests: thyrotoxicosis may precipitate atrial fibrillation and other arrhythmias urea and electrolytes: looking for disturbances such as a low potassium full blood count

Question 70

Palpitations presentation: What is the next step after first line investigations?

Answer 70

``` exclude an episode arrhythmia. Holter monitoring If no abnormality is found on the Holter monitor, and symptoms continue, other options include: external loop recorder implantable loop recorder ```

Question 71

In atrioventricular (AV) block, or heart block, there is impaired electrical conduction between the atria and ventricles.

Answer 71

true | 3 types

Question 72

First-degree heart block?

Answer 72

PR interval > 0.2 seconds | asymptomatic first-degree heart block is relatively common and does not need treatment

Question 73

What is Mobitz I/ Wenckebach

Answer 73

type 1 Second-degree heart block | progressive prolongation of the PR interval until a dropped beat occurs

Question 74

What is mobitz II?

Answer 74

type 2 Second-degree heart block | PR interval is constant but the P wave is often not followed by a QRS complex

Question 75

Third-degree (complete) heart block?

Answer 75

there is no association between the P waves and QRS complexes

Question 76

What is Torsades De Pointes?

Answer 76

form of polymorphic ventricular tachycardia associated with a long QT interval. It may deteriorate into ventricular fibrillation and hence lead to sudden death.

Question 77

How do you manage Torsades De Pointes?

Answer 77

IV magnesium sulphate

Question 78

What is Wolff-Parkinson White?

Answer 78

syndrome is caused by a congenital accessory conducting pathway between the atria and ventricles leading to a atrioventricular re-entry tachycardia (AVRT). As the accessory pathway does not slow conduction AF can degenerate rapidly to VF

Question 79

What are the ECG features of Wolff-Parkinson White?

Answer 79

short PR interval wide QRS complexes with a slurred upstroke - 'delta wave' left axis deviation if right-sided accessory pathway* right axis deviation if left-sided accessory pathway*

Question 80

What are the two of Wolff-Parkinson White types

Answer 80

``` type A (left-sided pathway): dominant R wave in V1 type B (right-sided pathway): no dominant R wave in V1 ```

Question 81

What are the associations of WPW?

Answer 81

``` HOCM mitral valve prolapse Ebstein's anomaly thyrotoxicosis secundum ASD ```

Question 82

What is the management of WPW?

Answer 82

definitive treatment: radiofrequency ablation of the accessory pathway medical therapy: sotalol***, amiodarone, flecainide sotalol should be avoided if there is coexistent atrial fibrillation as prolonging the refractory period at the AV node may increase the rate of transmission through the accessory pathway, increasing the ventricular rate and potentially deteriorating into ventricular fibrillation

Question 83

in the majority of cases, or in a question without qualification, Wolff-Parkinson-White syndrome is associated with left axis deviation

Answer 83

true

Question 84

The 2015 Resuscitation Council (UK) guidelines emphasise that the management of bradycardia depends on?

Answer 84

1. identifying the presence of signs indicating haemodynamic compromise - 'adverse signs' 2. identifying the potential risk of asystole

Question 85

In Peri-arrest rhythms: bradycardia | The following factors indicate haemodynamic compromise and hence the need for treatment?

Answer 85

shock: hypotension (systolic blood pressure < 90 mmHg), pallor, sweating, cold, clammy extremities, confusion or impaired consciousness syncope myocardial ischaemia heart failure

Question 86

What is the first line treatment of peri=arrest bradycardia with haemodynamic compromise?

Answer 86

Atropine (500mcg IV) is the first line treatment in this situation. If there is an unsatisfactory response the following interventions may be used: atropine, up to maximum of 3mg transcutaneous pacing isoprenaline/adrenaline infusion titrated to response Specialist help should be sought for consideration of transvenous pacing if there is no response to the above measures.

Question 87

What are the risk factors for asystole?

Answer 87

complete heart block with broad complex QRS recent asystole Mobitz type II AV block ventricular pause > 3 seconds (in peri-arrest bradycardia) if there is a satisfactory response to atropine specialist help is indicated to consider the need for transvenous pacing:

Question 88

What are J waves and what are they associated with?

Answer 88

small bumps at the end of the QRS complex. | hypothermia

Question 89

What are features of hypothermia?

Answer 89

``` bradycardia 'J' wave - small hump at the end of the QRS complex first degree heart block long QT interval atrial and ventricular arrhythmias ```

Question 90

Delta waves are associated with ?

Answer 90

Wolff-Parkinson-White Syndrome

Question 91

Saddle ST elevation is associated with?

Answer 91

pericarditis