atrial fibrillation.

What is atrial fibrillation?

Disorganized electrical activity in the atria causing irregular pulse.

What are the overall effects of atrial fibrillation?

Irregular ventricular contractions, tachycardia, heart failure, increased stroke risk.

What is the pathophysiology of atrial fibrillation?

Disorganized electrical activity overrides regular activity, causing uncoordinated atrial contraction and irregular ventricular contraction.

What are some lifestyle causes of atrial fibrillation?

Alcohol and caffeine.

How is atrial fibrillation often diagnosed?

As an incidental finding or after a stroke.

What is the role of the sinoatrial node in atrial fibrillation?

Produces organized electrical activity that coordinates atrial contraction.

What can happen to the blood in the atria during atrial fibrillation?

It can stagnate and form a blood clot (thrombus).

Where can a thrombus formed in the left atrium travel to?

The brain and block a cerebral artery, causing a stroke.

What is the mnemonic for common causes of atrial fibrillation?

SMITH: Sepsis, Mitral valve pathology, Ischaemic heart disease, Thyrotoxicosis, Hypertension.

What are some symptoms of atrial fibrillation?

Palpitations, shortness of breath, dizziness or syncope.

What is the key examination finding in atrial fibrillation?

Irregularly irregular pulse.

What are the two differential diagnoses for an irregularly irregular pulse?

Atrial fibrillation and ventricular ectopics.

What does a regular heart rate during exercise suggest?

A diagnosis of ventricular ectopics.

What investigation is required in all patients with an irregularly irregular pulse?

ECG.

What are the ECG findings in atrial fibrillation?

Absent P waves, narrow QRS complex tachycardia, irregularly irregular ventricular rhythm.

When may an echocardiogram be required?

In cases of valvular heart disease, heart failure, or planned cardioversion.

What is paroxysmal atrial fibrillation?

Episodes of atrial fibrillation that reoccur and spontaneously resolve back to sinus rhythm.

How long can episodes of paroxysmal atrial fibrillation last?

Between 30 seconds and 48 hours.

What investigations can be done for patients with a normal ECG and suspected paroxysmal atrial fibrillation?

24-hour ambulatory ECG (Holter monitor) or cardiac event recorder lasting 1-2 weeks.

What is valvular atrial fibrillation?

AF with significant mitral stenosis or a mechanical heart valve.

What is the assumption in valvular atrial fibrillation?

That the valvular pathology has led to atrial fibrillation.

What is non-valvular atrial fibrillation?

Atrial fibrillation without valve pathology or with other valve pathologies, such as mitral regurgitation or aortic stenosis.

What do the NICE guidelines recommend for patients with valvular heart disease?

Referral to a cardiologist for further assessment and management.

What are the two principles of treating atrial fibrillation?

Rate or rhythm control.

When do ventricular ectopics disappear?

When the heart rate gets above a certain threshold.

What is the purpose of rate control in atrial fibrillation?

To get the heart rate below 100 and extend diastole for ventricular filling.

What are the NICE guidelines for rate control in atrial fibrillation?

All patients with AF should have rate control as first-line, except in specific cases.

What are the options for rate control in atrial fibrillation?

Beta blockers, calcium-channel blockers, and digoxin.

When is rhythm control offered in atrial fibrillation?

In patients with a reversible cause, new onset AF, heart failure caused by AF, or symptoms despite rate control.

What is the goal of rhythm control in atrial fibrillation?

To return the patient to normal sinus rhythm.

How can rhythm control be achieved?

Through cardioversion or long-term medication use.

What are the choices for cardioversion?

Immediate or delayed cardioversion.

What is the most common beta blocker used for rate control in atrial fibrillation?

Bisoprolol.

When is digoxin used for rate control in atrial fibrillation?

Only in sedentary people with persistent AF, requires monitoring and has a risk of toxicity.

Which calcium-channel blockers are used for rate control in atrial fibrillation?

Diltiazem or verapamil.

What is the recommended anticoagulant for atrial fibrillation?

DOAC

What are the criteria for immediate cardioversion?

Present for less than 48 hours, causing life-threatening haemodynamic instability

What are the two options for immediate cardioversion?

Pharmacological cardioversion, Electrical cardioversion

What are the options for pharmacological cardioversion?

Flecainide, Amiodarone (drug of choice in patients with structural heart disease)

What is the goal of electrical cardioversion?

To shock the heart back into sinus rhythm

How is electrical cardioversion performed?

Using a cardiac defibrillator machine to deliver controlled shocks, usually with sedation or GA

When is delayed cardioversion used?

If AF has been present for more than 48 hours and the patient is stable

What is the recommended method for delayed cardioversion?

Electrical cardioversion

What is an alternative option for delayed cardioversion?

Transoesophageal echocardiography-guided cardioversion

Why should the patient be anticoagulated before delayed cardioversion?

To prevent the risk of mobilizing a blood clot and causing a stroke

What is the recommended duration of anticoagulation before delayed cardioversion?

At least 3 weeks

What is the management strategy for patients waiting for cardioversion?

Rate control

What is the first-line long-term rhythm control for atrial fibrillation?

Beta blockers

What is the second-line long-term rhythm control for atrial fibrillation?

Dronedarone (for maintaining normal rhythm after successful cardioversion)

When is amiodarone useful in long-term rhythm control?

In patients with heart failure or left ventricular dysfunction

What is a pill-in-the-pocket approach?

Taking a pill to terminate atrial fibrillation symptoms.

What is the usual treatment for a pill-in-the-pocket approach?

Flecainide.

What is the risk of flecainide in a pill-in-the-pocket approach?

Converting atrial fibrillation into atrial flutter with a fast ventricular rate.

Should patients with paroxysmal atrial fibrillation be anticoagulated?

Yes, based on their CHA2DS2-VASc score.

What are the options for ablation when drug treatment is not adequate?

Left atrial ablation or atrioventricular node ablation with a pacemaker.

Where is left atrial ablation performed?

Cath lab.

What is the process of left atrial ablation?

Inserting a catheter through a femoral vein to the heart, testing electrical signals, and applying heat to burn abnormal areas.

What is the aim of left atrial ablation?

To remove the source of arrhythmia and restore normal sinus rhythm.

What is the alternative to left atrial ablation?

Atrioventricular node ablation and a permanent pacemaker.

What is the result of radiofrequency ablation during left atrial ablation?

Scar tissue that does not conduct electrical activity.

What is the goal of left atrial ablation?

To restore normal sinus rhythm by removing the source of arrhythmia.

What are the requirements for a patient to use a pill-in-the-pocket approach?

Infrequent episodes without structural heart disease, ability to identify signs of atrial fibrillation, and understanding when to take the treatment.

What is atrioventricular node ablation?

Procedure to destroy connection between atria and ventricles.

What is the purpose of atrioventricular node ablation?

To prevent irregular electrical activity from passing to the ventricles.

What is required after atrioventricular node ablation?

Permanent pacemaker to control ventricular contraction.

What is the risk of people with AF having a stroke each year?

5%

What is the risk of people with AF on anti-coagulation having a stroke each year?

1-2%

By how much does anticoagulation reduce the risk of stroke?

About 2/3.

What is the risk of serious bleeding with anticoagulation treatment?

Around 2.5-8% per year.

What are the recommended first-line anticoagulants according to NICE guidelines?

DOACs

What is the second-line anticoagulant if DOACs are contraindicated?

Warfarin.

What are direct-acting oral anticoagulants (DOACs)?

Oral anticoagulants that do not require INR monitoring.

What are the direct factor Xa inhibitors?

Apixaban, edoxaban, and rivaroxaban.

What is the direct thrombin inhibitor?

Dabigatran.

How often are apixaban and dabigatran taken?

Twice daily.

How often are edoxaban and rivaroxaban taken?

Once daily.

What are the advantages of DOACs compared to warfarin?

No monitoring required, no issues with time in therapeutic range, no major interaction problems, equal or slightly better at preventing strokes, equal or slightly lower risk of bleeding.

What are the most common indications for DOACs?

Stroke prevention in atrial fibrillation, treatment of DVT and PE, prophylaxis of DVTs and PEs after hip or knee replacement.

What is the half-life of DOACs?

6-14 hours.

What is the purpose of a CT head in patients with a head injury while taking anticoagulation?

To assess for an intracranial bleed.

According to the NICE guidelines on head injuries, when should a CT head be done in patients with a head injury while taking anticoagulation?

Automatically, as it qualifies them for a CT scan.

What should patients starting on anticoagulation be informed about in the event of a head injury?

They will need medical attention (A&E) for this reason.

What is the most common reason for reviewing a patient after a fall?

Head injury.

What type of patients are DOACs suitable for?

Most patients, including patients with cancer.

What is the reversal agent for apixaban and rivaroxaban?

Andexanet alfa.

What is the reversal agent for dabigatran?

Idarucizumab.

What is the most common indication for DOACs?

Stroke prevention in patients with atrial fibrillation.

What is the treatment for DVT and PE?

DOACs.

What is warfarin?

Vitamin K antagonist

What is the role of vitamin K in clotting?

Essential for functioning of clotting factors

How does warfarin affect vitamin K?

Blocks vitamin K

What does prothrombin time measure?

Time it takes for blood to clot

What is the INR used for?

Assess anticoagulation by warfarin

How is the INR calculated?

Patient's prothrombin time compared to average healthy adult

What does an INR of 1 indicate?

Normal prothrombin time

What does an INR of 2 mean?

Prothrombin time twice that of average healthy adult

Why does warfarin require close monitoring?

To keep INR in range

When is warfarin usually given?

Once daily, around 6 pm in hospital

What is the target INR for AF?

2-3

What is time in therapeutic range (TTR)?

Percentage of time INR is in target range