Internal Medicine

Atrial fibrillation

introduction

With atrial fibrillation, our heart gets “out of step” and for various reasons beats irregularly. Approximately 1-2% of the total population suffer from this condition, causing the atrial fibrillation most common persistent cardiac arrhythmia represents.

If left untreated, the risk of serious consequences, such as a stroke, enormous. The most important help in confirming the diagnosis is the ECG, as characteristic changes in atrial fibrillation are very common there. The earlier therapeutic measures such as electrical cardioversion ("electric shock"), the more likely our heart will return to the desired rhythm. In almost all cases, those affected also have to take medication to “thin the blood”.

Atrial fibrillation - what happens in our heart?

Usually, all parts of our heart work together as a well-rehearsed team. This is how a regular rhythm of the heartbeat. The "main clock" for this is a small nerve node in the wall of the right atrium - the sinus node. From there, the electrical excitation is transmitted to other nerve points and fibers (e.g. AV nodes) within the heart muscle. This creates a directed wave of excitationso that one after another atria and ventricles contract and pump blood into our circulation.

At Atrial fibrillation on the other hand the heart gets "out of step". For various reasons, uncoordinated or undirected electrical excitations “circle” in the atria. Thus, the atria work independently of the ventricles and can no longer support them in their pumping function. Through the chaotic circular excitations decay the atria in convulsions in rapid succession and "flicker". Fortunately, not all of these faulty electrical impulses are transmitted to the ventricles, otherwise life-threatening ventricular fibrillation the consequence would be! The responsible nerve point is the AV node in the cardiac septum, which acts as a kind of "filter“Serves and ideally only transfers a few of the disturbing excitations to the chambers.

As the duration of the atrial fibrillation increases, a change in the heart muscle cells and their electrical properties can be observed. Experts then speak of "cardiac remodeling", which makes therapy much more difficult.

causes

Atrial fibrillation can have many causes. It is not uncommon for several diseases to lead to this arrhythmia. The most common are:

high blood pressure
Heart failure (heart failure)
Coronary heart disease (CHD)
Heart attack
Valvular heart disease
Heart muscle disease
Myocarditis
Hyperthyroidism
Potassium deficiency
alcohol
Medication
Pulmonary embolism
Sick sinus syndrome

Read more on the topic: Causes of atrial fibrillation

What is the relationship between atrial fibrillation and alcohol?

Alcohol consumption increases the risk of developing atrial fibrillation. Paroxysmal atrial fibrillation, in particular, the variant in which the arrhythmia occurs in attacks, can be triggered by excessive alcohol consumption. But regular alcohol consumption also increases the risk of atrial fibrillation significantly. A Swedish study found that the percentage risk of developing atrial fibrillation increases with the number of weekly alcoholic drinks. A Japanese study found evidence that the risk of atrial fibrillation in people who drink a lot of alcohol increases by 50% compared to people who drink very little. The risk continued to rise depending on the dose. However, the underlying physiological mechanism is still largely unclear. Patients who have heart disease or who already have atrial fibrillation are therefore recommended not to consume alcohol at all or only in small amounts. 24 g alcohol per day for men (equivalent to 0.5 l beer or 0.25 l wine) and 12 g alcohol per day for women (0.3 l beer, 0.15 l wine) are considered low.

Atrial fibrillation from stress

Stress is a relatively frequent trigger for an episode with atrial fibrillation in patients who already suffer from known attack-like atrial fibrillation. However, stress is rarely the real cause. Therefore, if atrial fibrillation has occurred, the cause must always be sought. In about 1/3 of the patients with atrial fibrillation there is no cause, but the other 2/3 have diseases such as high blood pressure, heart valve defects, coronary heart disease or heart muscle diseases as the cause. So stress can be the trigger for atrial fibrillation, but is rarely the only cause.

Symptoms

Palpitations and palpitations
Shortness of breath and shortness of breath
Chest pain
Anxiety and anxiety
dizziness
Reduced exercise capacity
sweat

Whether or not those affected notice their atrial fibrillation depends largely on their heart rate. The faster the heart beats per minute (e.g. 120 / min), the more likely the first symptoms are noticeable. Nevertheless, around a third of those affected do not feel any discomfort!

The atria are no longer able to adequately support the ventricles during the heart's action. Thus, the amount of blood transported per heartbeat is also reduced and organs are supplied with relatively less blood and oxygen. As a result, those affected often notice reduced performance, shortness of breath, dizziness, weakness or even fainting spells. It is not uncommon for patients to report noticeable “palpitations” or “palpitations”. Sometimes, however, an irregular pulse on the wrist can be the only clue.

Further information on this topic can be found at: Symptoms of atrial fibrillation

Heart rate in atrial fibrillation

Atrial fibrillation describes an irregular heart action, i.e. a cardiac arrhythmia. The heartbeat is usually regular. With atrial fibrillation, however, the heart does not beat rhythmically. How often the heart beats per minute (heart rate) is not defined for atrial fibrillation. There is atrial fibrillation with normal heart rate (normofrequency atrial fibrillation) but also atrial fibrillation with too slow (bradycardic atrial fibrillation or Bradyarrhythmia absoluta) or too fast heart rate (tachycardial atrial fibrillation or Tachyarrhythmia absoluta). Atrial fibrillation in particular, which is accompanied by a heart rate that is too fast, can lead to symptoms such as shortness of breath, a feeling of oppression or pressure on the chest. Normofrequency atrial fibrillation is often not even noticed by the patient.

Also read our topic: Heart rate and pressure in the chest- these are the causes

Difficulty breathing with atrial fibrillation

With atrial fibrillation, the heart no longer works as regularly as it should. This reduces its pumping function. This means that with atrial fibrillation blood can no longer be pumped as effectively as with a healthy heart. The faster the heart beats in atrial fibrillation, the worse its pumping capacity. And the less blood the heart pumps, the worse the body's oxygen supply. Therefore shortness of breath occurs (Dyspnea) especially with atrial fibrillation, which is associated with a heart rate that is too fast. Depending on the heart rate, the patients can no longer breathe properly, suffer from shortness of breath even during moderate or light exertion or even have the feeling at rest that they are short of air.

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Are there any signs of atrial fibrillation that I can see?

Atrial fibrillation is common. Many patients who suffer from atrial fibrillation do not even notice it. Often it is an incidental finding in the EKG. Signs of possible atrial fibrillation are rather unspecific: reduced resilience, shortness of breath during physical exertion, heart stumbling, chest pain or sudden feelings of oppression can be indicative. Such symptoms should generally be clarified, as they can also occur in cases of heart failure (Heart failure) or a heart attack. If there is a suspicion that atrial fibrillation is present, the person affected can measure their pulse. To do this, he places the tips of the middle and index fingers on the outside of the wrist just below the ball of the thumb on the skin. You should feel a faint throbbing. In a healthy heart, the pulse is regular. Many people occasionally have extra strikes that can be felt as dropouts or additional strikes. With atrial fibrillation, however, there is no longer any discernible rhythm, the pulse appears completely irregular. If atrial fibrillation is suspected, the attending physician should be consulted. He can write an EKG and, if necessary, initiate further necessary examinations.

diagnosis

The most important diagnostic method for atrial fibrillation is the EKG (electrocardiogram), as the disease typical patterns of change in the investigation shows. A short, conventional recording is often sufficient. In some patients, however, despite a high level of suspicion, there are initially no abnormalities in the ECG. In this case, a long-term ECG may be suitable, which usually records the heart activity over 24 hours.

As people get older, more and more people suffer from atrial fibrillation. For those over 80 years of age it is already almost 10%! Since "silent" cardiac arrhythmias often lead to strokes, especially in this group, it is advisable to occasionally feel the pulse from around the age of 65 in order to quickly discover any irregularities.

EKG

If your doctor suspects you have atrial fibrillation, he will pay particular attention to the following particularities when evaluating the ECG:

1.) Irregular spacing of the R-waves

The R wave is the most noticeable wave on the electrocardiogram and part of the QRS complex, which represents the spread of excitation within the heart chambers. The intervals between the individual R waves can provide information about the heart rate and regularity of the heartbeat. In the case of atrial fibrillation, the distances sometimes vary. significant, so that a rhythm disturbance can be concluded.

2.) Missing P-wave

In the EKG of a healthy person, the P wave is the first small, positive wave after the zero line. It represents the electrical excitation of the atria. Since precisely this process is disturbed in atrial fibrillation, affected people do not find any P wave.

3.) Flicker waves

Instead of the regular P waves, so-called "flicker waves" are very often found. They are an expression of the circular atrial excitation and are characterized by very fast (> 350 / min), small rashes.

1.) Paroxysmal atrial fibrillation

Behind the complicated term hides a Greek name for the word "paroxysmal". It occurs spontaneously and without any recognizable trigger and usually ends after a maximum of 48 hours. Although paroxysmal atrial fibrillation can last up to seven days, the 48 hour period is significant. After this time has elapsed, it is unlikely that our heart "jumps" into the correct sinus rhythm on its own.

2.) Persistent atrial fibrillation

If atrial fibrillation lasts longer than seven days and only disappears after the start of therapy (e.g. medication), one speaks of persistent atrial fibrillation.

3.) Permanent atrial fibrillation

By definition, permanent atrial fibrillation exists when neither electrical cardioversion nor medication that can correct the arrhythmia. Both doctor and patient then accept this condition and forego further electronic cardioversion attempts.

Therapy of atrial fibrillation

Any recoverable causes of atrial fibrillation should be clarified before starting therapy. Potassium deficiency or hyperthyroidism can e.g. Treat with medication relatively uncomplicated. In addition, concomitant diseases such as high blood pressure or heart failure must also be treated! Basically, the treatment of atrial fibrillation consists of heart rhythm and frequency control. In addition, the need for blood-thinning therapy (anticoagulation) must always be considered.

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Medication

Various drugs are suitable for controlling the heart rate and rhythm. State of health, type of atrial fibrillation and previous illnesses determine the individual therapy concept. If atrial fibrillation has only recently been present, intravenous administration of so-called "antiarrhythmics" can often restore a healthy heart rhythm. In order to dampen the heart rate which is often too fast, e.g. Beta blockers or cardiac glycosides. Fortunately, there have been some new developments on the pharmaceutical market in recent years, so that numerous innovations are available, especially for antiarrhythmics.

You can find more information on this topic at: Therapy of atrial fibrillation

Anticoagulation for atrial fibrillation

Anticoagulation means something like blood thinning. However, this does not mean that the blood is otherwise too thick, but that the risk of blood clots forming is increased. Due to the uncoordinated twitching of the atria, the blood flow gets “mixed up”, especially in the left atrial appendage. The resulting turbulence and eddies activate our blood platelets (thrombocytes) and thus lead to the formation of a blood clot (thrombus). In the worst case, the thrombus is transported onwards, clogs important blood vessels in the brain and thus causes a stroke. Anticoagulation means that the platelets are no longer able to form such dangerous blood clots so easily. However, not all those affected require blood-thinning therapy (anticoagulation), which is the case with atrial fibrillation. Therefore, most people with atrial fibrillation should receive a blood thinning. Young patients without any other illnesses can usually do without it.However, the older people get and the more pronounced their atrial fibrillation and possible concomitant diseases, the more likely anticoagulation is required. Blood thinners come in the form of syringes and tablets. The "thrombosis injections" are often used in hospitals. However, they are dosed in a higher dose for anticoagulation in atrial fibrillation than the syringes for thrombosis prevention. Since anticoagulation usually has to be lifelong, long-term injections are not advisable. Therefore there are alternative tablets. For many years, drugs from the group of vitamin K antagonists were standard tablets. This includes Falithrom® / Marcumar® (active ingredient: Phenprocoumon). These tablets have the disadvantage that they are metabolized very differently from person to person, so there is no standard dose. Rather, a blood value must be checked regularly to avoid over- or underdosing the drug. When taking Phenprocoumon, it is very important to keep an eye on the INR value. A newer group of anticoagulants no longer has this problem. We are talking about the new oral anticoagulants, or NOACs for short. These include Xarelto® (active ingredient: rivaroxaban) and Eliquis® (active ingredient: apixaban). They are taken in a fixed dose once or twice a day, unless there are disorders of kidney function. All of these drugs work by thinning the blood and thus counteracting strokes. There are few patients with atrial fibrillation who should not be receiving oral anticoagulation. This includes people who are very healthy except for atrial fibrillation (see section Score), people who have already suffered heavy bleeding or very old people at risk of falling.

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Beta blockers for atrial fibrillation

Beta blockers are drugs that affect the way your heart works. They are very commonly used to treat high blood pressure. But they also lower the heart rate and are therefore drugs that are very often prescribed for atrial fibrillation with a heart rate that is too fast. Some beta blockers are also said to have a rhythm-stabilizing effect, so they should help to ensure that atrial fibrillation changes to a normal rhythm or that the normal rhythm is maintained after changing. Examples of beta blockers are bisoprolol and metoprolol.

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What is atrial fibrillation ablation?

Catheter ablation is a treatment option for recurring atrial fibrillation or for patients who suffer from the symptoms of atrial fibrillation. The aim of ablation is to permanently restore normal sinus rhythm. Under local anesthesia, a catheter is first inserted through a small incision, usually in the groin via the inguinal vein, and advanced to the heart. With the help of this catheter, scars are then placed in certain areas of the heart wall and / or the pulmonary veins. These scars are supposed to switch off the areas of the heart in which unwanted spontaneous electrical excitation repeatedly leads to atrial fibrillation. The scars are set by heat, cold or a laser. To this end, diseased heart tissue, which transmits false excitations and thus triggers atrial fibrillation, is specifically desolated with heat and switched off. A part of the tissue is scarred or obliterated by means of high-frequency current, so that it can no longer transmit electrical signals. The ablation treatment is not always successful the first time, so it sometimes has to be carried out several times. Even then, however, there is no guarantee that the atrial fibrillation will be safely eliminated. So far, patients who do not have permanent atrial fibrillation, but in whom the atrial fibrillation occurs in attacks, have primarily been considered for ablation therapy. In technical jargon, this is from paroxysmal atrial fibrillation the speech. In the case of catheter ablation, the patient usually does not need anesthesia, he is awake or slightly sedated during the examination. The only thing that is somewhat painful is the insertion of the catheter over the groin;
After the ablation, those affected have to stay in bed for 12 hours and are usually allowed to leave the hospital the next day. Ablation is currently not a first-line therapy ("second-line therapy"). Therefore, it is mostly only used if drug therapy has been unsuccessful or intolerance. Thus, the ablation is effective but rarely appropriate. For this reason, only specialized and experienced specialist centers should perform the procedure. Nevertheless, the method can represent a real opportunity, especially for young patients. In addition to the catheter ablation described, surgical ablation can also be carried out in very special cases. During the operation, the defective heart tissue is removed by a cardiac surgeon under general anesthesia. Due to the higher complication rate, this procedure is only carried out if e.g. a bypass operation is planned and therefore surgical intervention is necessary anyway.

When do I need a pacemaker?

Pacemakers are used to treat certain cardiac arrhythmias. However, they are rarely used in atrial fibrillation. The only indication for implantation of a pacemaker for atrial fibrillation is Bradyarrhythmia absoluta, i.e. a heart rate that is significantly too slow in the context of atrial fibrillation. If the heart beats so slowly that the patient feels symptoms such as dizziness or even passes out, treatment must be given here. A 2-chamber pacemaker is usually installed. It then works both in the right atrium and in the right ventricle and ensures that the heart beats fast enough again. In the case of atrial fibrillation with a normal or too fast heart rate, a pacemaker is not an option as a therapeutic measure.

Read more on the topic: Pacemaker

Electric shock / cardioversion for atrial fibrillation

Cardioversion is a procedure used to stop atrial fibrillation immediately. This may be necessary at different times. For example, in a patient who has an unstable circulation due to atrial fibrillation. Action must be taken here quickly, the aim is to end the atrial fibrillation as soon as possible. But even in younger patients with new atrial fibrillation, an attempt can be made to end the arrhythmia with an electric shock. Especially in patients who have suffered from atrial fibrillation for years, the long-term chances of success of cardioversion are rather low.
With electrical cardioversion, the goal is to reactivate the primary pacemaker in our heart, the sinus node, with a brief electrical surge. This is intended to stop the chaotic circular excitations in the atrium and then return the heart to its normal sinus rhythm. The procedure is performed under short anesthesia and under careful ECG control. Since dangerous blood clots can easily form during this time, blood-thinning therapy must be started in preparation. Before cardioversion, it must be excluded that there is already a blood clot in the heart. Otherwise, the electric shock could catapult this clot from the heart into the blood vessels supplying the brain, where it could trigger a stroke.
To rule out a clot, a heart ultrasound is performed from the inside, i.e. via the esophagus (transesophageal echocardiography, TEA). If a clot is excluded, the patient is given a short anesthetic. When he sleeps, a shock is delivered via a defibrillator, which is carried away to the patient's heart via electrodes that are attached to the patient's body. Such a shock is often enough to get the heart back into rhythm. In most cases, however, patients must also take regular medication in order to maintain this rhythm. Even then, the recurrence rate, i.e. the rate at which atrial fibrillation will recur, is relatively high.

prophylaxis

The best prevention against atrial fibrillation is to avoid or control the triggering factors. E.g. High blood pressure or many heart diseases caused by one healthy and balanced lifestyle to a large extent prevented. First of all, take care of her Weight, a healthy diet and enough exercise. Apart from that, there is unfortunately no suitable prophylaxis.

forecast

Ultimately, the prognosis depends on the underlying human disease and can therefore not be generalized. For example, patients with pronounced cardiac insufficiency and accompanying atrial fibrillation Significantly worse prospects than people who temporarily suffer from atrial fibrillation due to an overactive thyroid.

Read more about this under What is the life expectancy with atrial fibrillation?

What is the relationship between atrial fibrillation and a stroke?

Patients with atrial fibrillation are at increased risk of having a stroke. The shimmering movement of the auricles can cause blood clots (Thrombi) in the heart. If such a clot detaches itself from the heart wall and flows with the bloodstream, it can reach the vessels supplying the brain and block one of the vessels there. The clot then sits like a plug in the vessel lumen and, in the worst case, closes it completely so that no more blood can flow through this vessel. In the case of a blood vessel that supplies the brain, this means that the area of the brain that is supplied by this blood vessel is no longer supplied with blood Ischemia. There are then various symptoms of a stroke. Which symptoms occur depends largely on which blood vessel in which area was blocked by the clot. In order to drastically reduce the risk of stroke with atrial fibrillation, the use of blood thinners is recommended for most patients with atrial fibrillation.

Also read our topic

Stroke - What Are The Signs?
Blood clots in the head

Atrial fibrillation score

There is a score that is used to assess the risk of developing a stroke in patients with atrial fibrillation. This score also gives a recommendation as to whether blood thinning (Anticoagulation) is recommended or not. This score is known in its expanded form as the CHA2DS2 Vasc score. The individual letters are acronyms for diseases. Since the score was stolen from English, the respective letter does not always match the corresponding illness in German.
Patients who suffer from congestive heart failure receive one point. Patients with high blood pressure (Hypertension) receive a point. Patients over 75 years of age receive two points, hence the 2 behind the A. Patients with diabetes mellitus receive one point. Patients with a history of a stroke or a TIA (transitory ischemic attack, "minor stroke") again receive two points, hence the 2 behind the S. V stands for vascular and refers to vascular diseases. Patients with pre-existing vascular diseases such as coronary artery disease (CHD) or peripheral arterial occlusive disease (PAD) receive one point. Patients between 65 and 74 years of age (A) receive one point. Female patients (sex = gender) receive one point. The number of points achieved can be between 0 and 9 points. Patients with 0 points do not need blood thinning. Female patients who have received a point based on their gender can be treated as 0 points, so they do not need a blood thinning. Blood thinning is recommended from 1 point. With exactly 1 point, this could theoretically also be done with ASA (Aspirin®). From 2 points - if there are no contraindications - oral anticoagulation must be initiated. The agents of choice here are new oral anticoagulants or vitamin K antagonists.

What is the life expectancy with atrial fibrillation?

In principle, atrial fibrillation does not limit the life expectancy of an otherwise healthy patient. Especially with patients who suffer from numerous pre-existing (heart) diseases and for whom atrial fibrillation is not treated, life expectancy can decrease. Overall, untreated atrial fibrillation is a risk factor, as it can trigger a stroke, for example. This, in turn, can significantly affect life expectancy. Atrial fibrillation should therefore always be treated - except in exceptional cases. By diluting the blood. In patients whose heart beats too quickly with atrial fibrillation or who have symptoms from atrial fibrillation, other medication measures must be taken in addition to blood thinning. Treated atrial fibrillation rarely reduces life expectancy these days.

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Can atrial fibrillation be fatal?

Atrial fibrillation sounds similar to ventricular fibrillation to the layperson. However, they are two completely different cardiac arrhythmias. While atrial fibrillation takes place in the atrium, the center of ventricular fibrillation is in the ventricle. Ventricular fibrillation is a life-threatening arrhythmia that is usually one Defibrillation (Shock delivery to the heart) is required to get the heart back into the right rhythm. Ventricular fibrillation is a common cause of the life-threatening circulatory disorder popularly known as cardiac arrest. Atrial fibrillation, on the other hand, carries only a very low risk of developing into ventricular fibrillation and is therefore rarely directly fatal. However, it can be dangerous, especially for patients with a previously damaged heart who are in crisis from atrial fibrillation with a heart rate that is too fast, as the heart can "exhaust itself". This can ultimately lead to acute heart failure. However, this is rarely the case. However, atrial fibrillation also increases the risk of developing a stroke. In the worst case, this can also be fatal.

Can I do sports with atrial fibrillation?

Atrial fibrillation often does not just happen, but has a triggering cause. These triggering causes include circulatory disorders of the coronary arteries (coronary heart desease, CHD), high blood pressure (arterial hypertension), Valvular heart disease, and heart muscle disease. Thyroid diseases can also lead to atrial fibrillation. In about 1/3 of the atrial fibrillation cases, however, no cause can be found. Nonetheless, it is extremely important to look for a triggering cause the first time atrial fibrillation occurs. If, for example, a circulatory disorder of the heart vessels is the cause, further sport without prior treatment can lead to dangerous complications. If the cause of the atrial fibrillation has been found and treated or the main possible causes have been safely ruled out, sport can still be done. It should be noted, however, that certain drugs that are used to lower the heart rate and to control rhythm in atrial fibrillation (beta blockers) limit the maximum heart rate and thus the performance. Patients who are known to have atrial fibrillation should also take care not to exhaust themselves and to pause immediately if symptoms such as shortness of breath, chest pain or an excessive racing heart appear. Basically, atrial fibrillation is no reason to stop doing sports. However, the above points should be observed.

Also read: Is it allowed to do sports with cardiac arrhythmias? Can you do sports with atrial fibrillation?

What is the difference between atrial fibrillation and atrial flutter?

Atrial fibrillation and atrial flutter are two different types of cardiac arrhythmias that originate in the atrium. With atrial fibrillation, the atrium contracts 300 to 600 times per minute, which is far too often. As a comparison: A healthy person has a heart rate of 60-100 beats per minute, so the heart contracts 60 to 100 times per minute. With atrial fibrillation, the atrium contracts much more often and thus triggers excitation of the heart. Fortunately, however, not all of these excitations go to the ventricle, it would be fatal. In atrial flutter, the atrial frequency is slightly lower than in atrial fibrillation. It is around 240 to 340 contractions per minute. As a rule, not all of these are transferred to the heart chamber. In contrast to atrial fibrillation, atrial flutter rarely occurs in an otherwise healthy heart.With atrial flutter, as with atrial fibrillation, there is also the risk that clots will form, which can trigger a stroke. Atrial flutter and atrial fibrillation can be differentiated using the ECG. In contrast to atrial fibrillation, atrial flutter, which occurs again and again, usually has to be ended by ablation treatment; drug therapy usually does little to help.

For more information, see: Atrial flutter and atrial fibrillation

Degree of disability in atrial fibrillation

The recognition of a degree of disability is an individual decision that primarily takes into account how severely a disease or ailment restricts the person concerned in everyday life. Therefore, no general statement on the degree of disability in atrial fibrillation can be made here. However, atrial fibrillation is not a typical condition for acquiring a degree of disability.

What is intermittent atrial fibrillation?

Intermittent atrial fibrillation is atrial fibrillation that is not permanent. It occurs every now and then, but it disappears completely in the meantime. One speaks here of a paroxysmal, atrial fibrillation that occurs again and again suddenly.

Pulmonary embolism

Atrial fibrillation and pulmonary embolism have one thing in common: in most cases both diseases must be treated with blood-thinning medication (Anticoagulants) be treated. In pulmonary embolism, a blood clot gets stuck in one of the pulmonary vessels, reducing the blood supply to the lungs. However, the two diseases have nothing to do with each other in causal terms. While atrial fibrillation can cause clots that can trigger a stroke, the clot in pulmonary embolism is usually caused by a thrombosis in the leg.