ATRIAL FIBRILLATION &

ATRIAL FLUTTER

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What is Atrial fibrillation?

• Atrial fibrillation or AF, is the most common type of arrhythmia . An arrhythmia is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.

• AF occurs if rapid, disorganized electrical signals cause the heart's two upper chambers—called the atria—to fibrillate. The term "fibrillate" means to contract very fast and irregularly.

• In AF, blood pools in the atria. It isn't pumped completely into the heart's two lower chambers, called the ventricles. As a result, the heart's upper and lower chambers don't work together as they should.

What is Atrial Flutter

• AFL is a heart rhythm disorder that is similar to the more common A Fib. In AFib, the heart beats fast and in no regular pattern or rhythm. With AFL, the heart beats fast, but in a regular pattern. The fast, but regular pattern of AFL is what makes it special. AFL makes a very distinct "sawtooth" pattern on an electrocardiogram (ECG)

CLASSIFICATION OF ATRIAL FIBRILLATION

• According to its duration Atrial fibrillation is classified into paroxysmal, persistent or permanent (the three P’s).

• Paroxysmal atrial fibrillation is self-limiting and sinus rhythm restores spontaneously. Paroxysmal atrial fibrillation lasts for less than 7 days and does not require intervention to convert to a normal rhythm such as electrical or chemical cardioversion.

• Persistent atrial fibrillation lasts for greater than 7 days. The term persistent is used when there is a plan to use a rhythm control strategy and return the patient to sinus rhythm.

• Permanent atrial fibrillation is present when atrial fibrillation is present 100% of the time for greater than 7 days and there are no interventions planned to restore sinus rhythm.

• According to its symptoms Atrial Fibrillation can be:Symptomatic:in this case patients present the typical symptoms of this arrhythmia.

• Asymptomatic: in this case patients perceive no symptoms at all. This implies a very risky condition, because the patient is not aware of the presence of the arrhythmia. And indeed, suffering from Atrial Fibrillation without being aware of its presence means not treating it - a fact that severely increases the risk of stroke

CLASSIFICATION OF ATRIAL FLUTTER

• Typical Atrial Flutter (Common, or Type I Atrial Flutter)• Involves the IVC(Idioventricular Rhythm) & tricuspid isthmus in the

reentry circuit. Can be further classified based on the direction of the circuit:

• Anticlockwise Reentry. This is the commonest form of atrial flutter (90% of cases). Retrograde atrial conduction produces:

• Inverted flutter waves in leads II,III, aVF• Positive flutter waves in V1 – may resemble upright P waves• Clockwise Reentry. This uncommon variant produces the opposite

pattern:• Positive flutter waves in leads II, III, aVF• Broad, inverted flutter waves in V1

• Atypical Atrial flutter (Uncommon, or Type II Atrial Flutter)

• Does not fulfil criteria for typical atrial flutter.

• Often associated with higher atrial rates and rhythm instability.

• Less amenable to treatment with ablation.

ETIOLOGY OF ATRIAL FIBRILLATION• Identifying the cause of atrial fibrillation can not be under

emphasized as the treatment of the cause is frequently necessary to eliminate atrial fibrillation. The classic mneumonic “PIRATES” encompasses a vast majority of the causes of atrial fibrillation:

• Pulmonary embolus, pulmonary disease, post-operative, pericarditisIschemic heart disease, idiopathic (“lone atrial fibrillation”), intravenous central line (in right atrium)Rheumatic valvular disease (specifically mitral stenosis or mitral regurgitation)Anemia, alcohol (“holiday heart”), advanced age, autonomic tone (vagally mediated atrial fibrillation)Thyroid disease (hyperthyroidism)Elevated blood pressure (hypertension), electrocutionSleep apnea, sepsis, surgery

• Historically, hypertension was thought to be the most common cause of atrial fibrillation, however obstructive sleep apnea is present in about 40% of atrial fibrillation patients and it is we

• ll known that obstructive sleep apnea causes hypertension. The exact proportion of atrial fibrillation caused directly from obstructive sleep apnea remains unclear.

SIGNS AND SYMPTOMS OF ATRIAL FIBRILLATION

• Atrial fibrillation can cause a variety of symptoms. Some patients with atrial fibrillation may have no symptoms at all and may even be unaware that they have this problem. In many patients, atrial fibrillation is only discovered by chance, at a routine health-check. The common symptoms of atrial fibrillation are........

• Common signs and symptoms of atrial fibrillation:• Irregular pulse• Palpitations or racing irregular heart-beats• Shortness of breath• Feeling overtired or lacking energy• Dizziness or confusion• Light-headedness or fainting• Feelings of fear or anxiousness• Chest discomfort or chest pain

RISK FACTORS OF ATRIAL FIBRILLATION

• Atrial Fibrillaton is typical of elderly age, but there are other conditions that can favour its insurgence, like co-morbidities and risk factors. 

Co-morbidities - Valvular heart disease - Hypertensive heart disease- Ischemic heart disease - Cardiomyopathies- Heart failure 

COMPLICATIONS OF ATRIAL FIBRILLATION

• Stroke. In atrial fibrillation, the chaotic rhythm may cause blood to pool in your heart's upper chambers (atria) and form clots. If a blood clot forms, it could dislodge from your heart and travel to your brain. There it might block blood flow, causing a stroke.

• The risk of stroke in atrial fibrillation depends on your age (you have a higher risk as you age) and on whether you have high blood pressure, diabetes, a history of heart failure or previous stroke, and other factors. Certain medications, such as blood thinners, can greatly lower your risk of stroke or the damage to other organs caused by blood clots.

• Heart failure. Atrial fibrillation, especially if not controlled, may weaken the heart and lead to heart failure — a condition in which your heart can't circulate enough blood to meet your body's needs.

DIAGNOSIS• In many situations atrial fibrillation can be detected by

simply feeling the pulse in your wrist or by a doctor listening to your heart by with a stethoscope. The presence of an irregular and often fast heart beat would suggest that you have may have atrial fibrillation. However, the diagnosis of atrial fibrillation should always be confirmed by recording a trace of the electrical signals from the heart, using a testCALLEDan electrocardiogram (or simply ECG). It is necessary to confirm the diagnosis of atrial fibrillation by ECG because irregular heart-beats can also be present in other heart conditions (arrhythmias)

 In the presence of atrial fibrillation, the ECG will highlight the absence of P waves, that are replaced by small irregular oscillations, the so-called f waves.

Furthermore, the interval between one beat and another, known as the R-R interval, isn't always the same.

ECG IN CASE OF ATRIAL FLUTTER

Narrow complex tachycardiaRegular atrial activity at ~300 Beats per minute.Flutter waves  (“saw-tooth” pattern) best seen in leads II, III, aVF  —  may be more easily spotted by turning the ECG upside down!Flutter waves in V1 may resemble P wavesLoss of the isoelectric baseline

ECG SAMPLES IN ATRIAL FLUTTER

EXAMPLE 01There are inverted flutter waves in II, III + aVF at a rate of 300 bpm (one per big square)There are upright flutter waves in V1 simulating P wavesThere is a 2:1 AV block resulting in a ventricular rate of 150 bpmNote the occasional irregularity, with a 3:1 cycle seen in V1-3This is the classic appearance of anticlockwise flutter.

EXAMPLE 02Atrial Flutter with 2:1 BlockThere is a narrow complex tachycardia at 150 bpm.There are no visible P waves.There is a sawtooth baseline in V1 with flutter waves visible at 300 bpm.Elsewhere, flutter waves are concealed in the T waves and QRS complexes.The heart rate of 150 bpm makes this flutter with a 2:1 block.

HOLTER MONITORING• Detection of atrial fibrillation may be more difficult in

people who do not have it all the time, where the irregular heart rhythm comes and goes by itself- this is known as paroxysmal atrial fibrillation. If you have paroxysmal atrial fibrillation then it may be necessary to have the ECG tracing recorded for 24 hours or longer (sometimes for 7 or 14 days if atrial fibrillation episodes are rare). This test, oftenCALLED “Holter monitoring” is done using a small device attached by wires to 4 special stickers (electrodes) placed on your chest. The device is easy to carry and is hardly noticeably under clothes.

You do not need to stay in hospital for this test and can carry on with most of your usual daily activities. You will probably be asked to keep a diary of your activities and symptoms (if any) you experience (palpitations, dizzy spells or chest pains etc) while wearing the monitor.  This portable ECG device is carried in your pocket or worn on a belt or shoulder strap.

STRESS TESTDuring stress testing, you exercise to make your heart work hard and beat fast while heart tests are done

EVENT RECORDER• Event recorder. This portable ECG device is intended to

monitor your heart activity over a few weeks to a few months. You activate it only when you experience symptoms of a fast heart rate.

• When you feel symptoms, you push a button, and an ECG strip of the preceding few minutes and following few minutes is recorded. This permits your doctor to determine your heart rhythm at the time of your symptoms

Transesophageal Echocardiography• Echocardiogram. In this noninvasive test, sound waves are used to

produce a video image of your heart. Sound waves are directed at your heart from a wand-like device (transducer) that's held on your chest (transthoracic echocardiogram). The sound waves that bounce off your heart are reflected through your chest wall and processed electronically to provide video images of your heart in motion, to detect underlying structural heart disease.

• Doctors may conduct a type of echocardiogram in which they insert a flexible tube with a transducer attached and guide it down your throat into your esophagus (transesophageal echocardiography). In this test, sound waves are used to produce images of your heart, which may be seen more clearly with this type of echocardiogram. Doctors may use this test to detect blood clots that may have formed in your heart.

OTHER TESTS• Chest X Ray• A chest x ray This test can show fluid buildup in the

lungs and signs of other AF complications.• Blood Tests• Blood tests check the level of thyroid hormone in your

body and the balance of your body's electrolytes.

TREATMENT• Blood Clot Prevention• People who have AF are at increased risk for stroke. This is

because blood can pool in the heart's upper chambers (the atria), causing a blood clot to form. If the clot breaks off and travels to the brain, it can cause a stroke.

• Preventing blood clots from forming is probably the most important part of treating AF. The benefits of this type of treatment have been proven in multiple studies.

• Doctors prescribe blood-thinning medicines to prevent blood clots. These medicines include warfarin (Coumadin®), dabigatran, heparin, and aspirin.

• People taking blood-thinning medicines need regular blood tests to

check how well the medicines are working.

RATE CONTROL• Rate control is the recommended treatment for most

patients who have AF, even though an abnormal heart rhythm continues and the heart doesn't work as well as it should. Most people feel better and can function well if their heart rates are well-controlled.

• Medicines used to control the heart rate include beta blockers (for example, metoprolol and atenolol), calcium channel blockers (diltiazem and verapamil), and digitalis (digoxin).

Resetting your heart's rhythm• Electrical cardioversion. In this brief procedure, an electrical

shock is delivered to your heart through paddles or patches placed on your chest. The shock stops your heart's electrical activity momentarily. When your heart begins again, the hope is that it resumes its normal rhythm. The procedure is performed during sedation, so you shouldn't feel the electric shock.

• After electrical cardioversion, your doctor may prescribe anti-arrhythmic medications to help prevent future episodes of atrial fibrillation. Medications may include:

• Dofetilide (Tikosyn)• Flecainide• Propafenone (Rythmol)• Amiodarone (Cordarone, Pacerone)

CATHETER AND SURGICAL PROCEDURES

• Catheter ablation  may be used to restore a normal heart rhythm if medicines or electrical cardioversion don't work. For this procedure, a wire is inserted through a vein in the leg or arm and threaded to the heart.

• Radio wave energy is sent through the wire to destroy abnormal tissue that may be disrupting the normal flow of electrical signals. 

• Sometimes doctors use catheter ablation to destroy the atrioventricular (AV) node. The AV node is where the heart's electrical signals pass from the atria to the ventricles (the heart's lower chambers). This procedure requires your doctor to surgically implant a device called a PACEMAKER, which helps maintain a normal heart rhythm.

MAZE SURGERY• Another procedure to restore a normal heart

rhythm is called maze surgery. For this procedure, the surgeon makes small cuts or burns in the atria. These cuts or burns prevent the spread of disorganized electrical signals.

• This procedure requires open-heart surgery, so it's usually done when a person requires heart surgery for other reasons, such as forheart valve disease (which can increase the risk of AF).

How Can Atrial Fibrillation Be Prevented?

• Following a healthy lifestyle and taking steps to lower your risk for heart disease may help you prevent atrial fibrillation (AF). These steps include:

• Following a heart healthy diet that's low in saturated fat, trans fat, and cholesterol. A healthy diet includes a variety of whole grains, fruits, and vegetables daily.

• Not smoking.• Being physically active.• Maintaining a healthy weight.

• If you already have heart disease or other AF risk factors, work with your doctor to manage your condition. In addition to adopting the healthy habits above, which can help control heart disease, your doctor may advise you to:  

• Follow the DASH eating plan to help lower your blood pressure.• Keep your cholesterol and triglycerides at healthy levels with dietary

changes and medicines (if prescribed).• Limit or avoid alcohol.• Control your blood sugar level if you have diabetes.• Get ongoing medical care and take your medicines as prescribed.

THANK YOU

The most essential part of a student’s knowledge is obtained.....not in the lecture room but at the bedside.Nothhing seen there is lost; the rhythms of disease are learned by frequent repitition;Its unforeseen occurences stamp themselves indelibly in the memory.

OLIVER WENDELL HOLMES,M.D.