Thread: Management of Atrial Fibrillation

CARDIOLOGY: CASE WRITE UP

A 59 year old malay man, from Melaka. He has hypertension for the past 6 months and also COAD for the past few years. He is currently on Perindropil 4mg once a day and Metered Dose Inhaler (MDI) Ventolin on need basis. He came to the emergency department presenting with complaints of palpitation for the past 3 days.
In the emergency department, his vitals were taken, BP: 140/70; pulse: 120 beats/minute, irregularly irregular rhythm, normal volume. He was conscious and orientated. ECG showed fibrilliform waves, absent P wave and irregular R-R intervals. There were no signs of ischemia. He was treated as a chronic stable atrial fibrillation. The treatment was amidarone 300mg in 100ml dextrose 5% and aspirin stat 300mg. Once the rate was controlled and vitals were all stable he was shifted to the ward.
On history, he had this sudden onset of palpitation 2 to 3 times a day and it lasts about 10 to 15 minutes with the last episode going up to 20 minutes. All the time when it happens he is at rest. He also revealed that over the past few months he has noticed that he is very anxious and highly irritable, and has increased appetite but has lost weight about 6kg in 4 months. However he claims he has no tremors, heat intolerance, excessive sweating, diarrhea. He has no diabetes and no known allergies, no other significant past medical or surgical history. No one in the family had any thyroid problems. He is smoker but has stopped for the past 17 years. No alcohol intake. He stays in a kampong house with wife and 5 children.
On examination, patient had tremors on his hands, there is lid lag but no other eye signs were prominent. His blood pressure: 145/65; pulse was 88 beats/minute irregularly irregular, normal volume. There is a midline neck swelling which moves on swallowing: 4 by 5cm, smooth surface, well define margin, and firm in consistency and non tender. On cardiac examination, apex beat not shifted. S1 and S2 heard with loud intensity Pulse deficit is present about 20 beats. No other remarkable findings on other examination.
The investigations done were full blood count which revealed anemia and thrombocytopenia. The full blood picture was of a normocytic and normochromic anemia. T4 and TSH results were pending, ultrasound of neck and Echocardiography was planned. Other investigations were normal. He is currently on 0.125mg digoxin daily, aspirin and anticoagulant therapy is being planned.

Diagnosis: Atrial Fibrillation due to hyperthyroidism.

In this case I learnt the management basic principle of management of Atrial Fibrillation.
Common causes: Myocardial infarction, valvular heart diseases, hypertension, hyperthyroidism, sino-atrial disease, congenital heart problem, cardiomyopathy and idiopathic.

Features: Palpitation, giddiness, chest pain, syncope, hypotension, irregular pulse and ECG changes.

In the management the aim is to have rate and rhythm control. The approach is divided into acute and chronic.

Acute: onset less than 48 hours. If the patient is stable, no chest pain, BP is in normal limits, no reduced mentation. Drugs like verapamil, B-blockers (iv propanolol), Amiodarone, Adenosine( 30 seconds to act), or Digoxin.
If the patient is unstable, BP drops, decreased mentation, chest pain then cardioversion is given. If patient is conscious, take consent and sedate the patient prior to cardioversion. Synchronous version given at 100Joules first, then increase as required.

Chronic: Longer period of time patient has the problem. Stable patient it is more important to control rate so drugs are given, as given for this patient. Then the rhythm can regularized. In unstable patients immediately cardioversion as mentioned above should be done.

Good write up.
Can you summarize the difference in he treatment of acute onset atrial fibrillation Vs chronic atrial fibrillation?

MANAGEMENT OF ACUTE AND CHRONIC ATRIAL FIBRILLATION

Aims: control the rate, restore the rhythm, hemodynamic stability, prevent embolization. Treat underlying cause if present.

ACUTE

Commonly due to current illness,

Onset less than 48 hours.

Patient is stable; mental status normal, BP normal, no chest pain

Yes
Medical management
1. Control rate: verapamil 5-10mg IV,
propanolol 1mg IV n 2 minutes,
Digoxin 0.25-0.5 mg IV
2. Restore rhythm: Amiodarone
3. If this fails then cardioversion can be tried after anticoagulant therapy pre and post version.


No
Cardioversion using synchronous DC starting at 100J.

Once patient is rate and rhythm controlled, amiodarone or quinidine can be used to prevent recurrence.
If both methods are not successful, just control rate with verapamil, propanolol, or digitalis and long term anticoagulant therapy (warfarin).
If there is an current underlying cause like pericarditis or thyrotoxicosis, it should be treated.

CHRONIC

Patient is stable; mental status normal, BP normal, no chest pain

Yes
Medical management (rate is priority)
1. Control rate: verapamil 5-10mg IV,
propanolol 1mg IV n 2 minutes,
Digoxin 0.25-0.5 mg IV
No
Cardioversion using synchronous DC starting at 100J.

When cardioversion is to be done, a transesophageal ECHO should be done to rule out any thrombus, if none heparin is injected and version is done. This is followed by warfarin for 4 weeks. If there is an thrombus, it is delayed with 3 weeks of warfarin and after the cardioversion 4 weeks of warfarin.
Amiodarone or quinidine can be used to prevent recurrence.
If rate cannot be controlled, Radio requency catheter ablation and pacemaker implantation can be tried.

Good. What you have written is a nice summary of the management of atrial fibrillation.