atrial fibrillation

Question 1

AF is

Answer 1

an arrhythmia cause by disorganised electrical activity in the atria usually leading to rapid and irregular ventricular rate

It is an important cause of morbidity and mortality due to heart failure, stroke and thromboembolism

Question 2

Different types of AF

Answer 2

• acute onset - started last 24-48 hours
• paroxysmal - recurrent and usually self-terminating - usually lasting < 7 days
• persistent - lasts longer than 48 hours and does not revert spontaneously to sinus rhythm.
• permanent - long standing and not amendable to cardioversion

Question 3

Cardiac and non cardiac causes of AF

Answer 3

• Cardiac - IHD, hypertension, rheumatic heart disease, cardiomyopathy, pericardial disease
• Non cardiac - thyrotoxicosis, acute infection, pulmonary disease (pneumonia, malignancy, effusion), alcohol XS (acute or chronic) preoperative period.

Question 4

Common symptoms in AF

Answer 4

those similar to HF
-breathless
-fatigue
pulmonary and peripheral oedema, palpitations, stroke, systemic thromboembolism

Question 5

Diagnostic tests

Answer 5

• ECG (p-waves and irregular narrow QRS complexes)
• TFTS (rule out thyrotoxicosis)
• LFT’s - if elevated may be alcohol
• CXR - pulmonary?
• Echo (TTE - trans thoracic echo)
• TOE trans oesophageal echo

Question 6

Aims of AF treatment

Answer 6

• reduce stroke risk
• control related symptoms especially those of HF
• control ventricular rate (rate control)
• cardiovert and maintain sinus rhythm (rhythm control)

Question 7

drugs care used to encourage prev aims but practitioners should also

Answer 7

• give lifestyle advice
• treat any underlying cause e.g. thyrotoxicosis
• stop ivabradine if this is prescribed in patients with AF

Question 8

Treatment

Answer 8

Anticoagulation for all

Rate control

• beta blocker (not stool)
• rate limiting CCB (verapamil, diltiazem)
• only consider digoxin mono therapy in sedentary patients presenting with pulmonary oedema or HF.
• if mono therapy doesn’t work then combine

Question 9

What do we never use together due to the risk of heart block

Answer 9

VERAPAMIL AND BETA BLOCKER

Question 10

When should we consider rhythm control in AF patients

Answer 10

When there is a reversible cause e.g. acute infection, HF primarily due to new onset AF (less than 48 hours duration)

Question 11

Pharmacological rhythm control

Answer 11

(<48 hours of symptoms)

• IV felcainide (if no IHD, structural HD or cHD)
• IV amiodorone
• Electrical

if >48 hours then therapeutic anticoagulation with warfarin or NOAC should be given for 3 weeks prior to cardioversion or TOE guided cardioversion to rule out the presence of a thrombus. Continuation of anticoagulation post cardioversion depends on the patients stroke risk but it is usually for 4 weeks.
-Amiodarane may be used for four weeks before elective cardioversion and continued for up to one year to increase the success rate

Standard beta blockers are first line for long term rhythm control.

Question 12

What do we give in long-term rhythm control if patients are C/I to beta blockers

Answer 12

• flecainide or profafenone if no IHD or CHD
• dronedarone if np LVSD or CHF

We can give amiodarane if LVSD or CHF are present

Question 13

Pill in the pocket options

Answer 13

• Flecainide - >70kg = 300mg. <70kg = 200mg.
• Propafenone >70kg = 600mg. <70kg = 450mg

Recommended in patients who don’t have CHF or IHD and when the AF occurs they are not haemodynamically unstable. These patients won’t get AF very often. Should be taken if the AF lasts longer than 5 minutes however they should go to hospital if it lasts longer than 6-8 hours.

No more than 1 in 24 hours.

Question 14

CHA2DS2VASC

Answer 14

Congestive Heart failure = 1 
Hypetenstion = 1
Age >75 = 2    Age 65-75=1
Diabetes = 1
Stroke, TIA, thrombus = 2
Vascular disease (pre MI, aortic plaque, peripheral artery disease)= 1
Female = 1

Offer oral anticoagulation in patients with chadsvasc score >2 - taking bleeding risk into account.

Question 15

HASEBLED

Bleeding risk in AF

Answer 15

Hypertension >160 systolic) = 1
Abnormal liver or renal = 1
Prev stroke = 1
Bleeding (major or preposition) = 1
Lavine INR = 1 
Elderly >65 = 1
Drugs (Antiplatelets, NSAIDs) = 1
Alcohol use > 8 weeks per 

Score >3 = high risk

Question 16

Do not offer women and men anticoagulation with

Answer 16

chadsvasc score

Men = 0

Women = 1

Question 17

NOACS are licensed for us in patients with…

Answer 17

non-valvular AF and one stroke risk factor…

Question 18

Combination of anticoagulant and aspirin

Answer 18

• warfarin and aspirin in patients who have had MI and have had it managed medically, have undergone balloon angioplasty or have undergone artery bypass graft surgery.
• consider combining anticoagulant with anti platelets in patients that had have MI and undergone PCI with bare metal or drug eluting stents

Question 19

Examples of potential causes of AF

Answer 19

• HTN
• Infection
• peri-operative period

Question 20

are AF patients always tachycadic?

Answer 20

No

Question 21

Which statement about paroxysmal AF is true?

Answer 21

Digoxin should be avoided in paroxysmal AF as it can worsen episodes

Question 22

Which statements about paroxysmal AF are false

Answer 22

• Patients don’t need anticoagulation when they are in sinus rhythm
• It should be managed using rate control strategy
• Episodes of AF will always need drug treatment
• episodes of Af usually last 7 days

Question 23

Flecainide should be avoided in patients with

Answer 23

IHD

Question 24

Would we no deny a patient of anticoagulation sole on the risk of falls?

Answer 24

No