Detecting and Treating Atrial Fibrillation

When the heart is completely out of rhythm, it is often referred to as atrial fibrillation in the context of cardiac arrhythmias. This disturbance in the rhythm of the heart is comparatively common. What is atrial fibrillation, how do you recognize the symptoms, and what treatment helps to get the heart back into the right rhythm? Find out that and more here.

How does atrial fibrillation develop?

The human heart beats about 60 to 100 times per minute. In this way, it pumps blood ceaselessly through our body. It requires perfectly coordinated action of the two larger ventricles and two smaller atria. Between the atria and the ventricles are the so-called atrioventricular valves (AV valves for short), which act like a valve to prevent blood from flowing back into the atria. When the atria contract, blood is transported into the ventricles. As soon as they are completely filled, they also contract and pump the blood into the circulation. In order for this coordinated pumping process to take place, it is necessary for specialized cells of the so-called sinus node to transmit electrical impulses to the atria and from there to the heart chambers (AV node). Occasionally, the heart gets a little out of sync. This is not bad. But it can also get completely out of rhythm, as is the case with rare, life-threatening ventricular fibrillation and common atrial fibrillation. About 1 million – especially elderly – patients in Germany have atrial fibrillation. In their hearts, the excitation wave emanating from the sinus node loses its direction. The atria then no longer contract, but only twitch unrhythmically up to 600 times per minute.

Atrial fibrillation as the most common cardiac arrhythmia

Atrial fibrillation results in the heart chambers no longer filling properly and the heart’s pumping capacity is reduced. There are several types of this arrhthmia:

  • We speak of paroxysmal atrial fibrillation when it occurs in attacks and the disturbances disappear on their own after hours or days.
  • If it does not stop on its own and must be treated, it is called persistent atrial fibrillation.
  • In extreme cases, there is permanent atrial fibrillation, which can not be controlled by common measures, because electrical and mechanical remodeling processes have greatly changed the atria. Problematically, atrial fibrillation is self-reinforcing because the atrial cells change so that they become electrically activatable at an ever-increasing rate.

In contrast, atrial flutter, which is less common than atrial fibrillation, is when the atria contract 250 to 300 times per minute. Without drug treatment, atrial flutter often leads to palpitations.

Causes of atrial fibrillation

Possible causes of atrial fibrillation include underlying diseases of the heart, such as narrowing of the coronary arteries and heart muscle disease. In addition, the following aspects of health history increase the risk for cardiac arrhythmias such as atrial fibrillation:

  • Cardiac surgery
  • A heart attack
  • Pulmonary embolisms
  • Inflammation of the heart muscle tissue
  • Chronic lung diseases
  • The chronic sleep apnea syndrome
  • Hyperthyroidism

High blood pressure, abnormally altered heart valves (especially the mitral valves), congenital heart defects, heavy nicotine use and increasing age are other risk factors. Atrial fibrillation can also be acutely triggered by excessive alcohol consumption (holiday-heart syndrome) and emotional stress. However, there are also cases in which no cause of atrial fibrillation can be determined.

Atrial fibrillation: typical symptoms

If the heart is only out of rhythm for a short time, most patients do not even notice it – this is called silent atrial fibrillation. If the fibrillation lasts longer, the following symptoms occur:

  • Completely irregular pulse
  • Shortness of breath
  • Feelings of anxiety
  • Weakness
  • Shortness of breath
  • Water retention

How is the diagnosis made?

Early diagnosis and quickly initiated treatment at the first signs of atrial fibrillation are important. To make the diagnosis, the physician palpates the pulse and listens to the patient with a stethoscope. He or she can confirm the diagnosis with an electrocardiogram (ECG).Experts recommend regular screening with ECG measurements in patients 65 and older because many people have atrial fibrillation without knowing it.

How dangerous is atrial fibrillation?

Atrial fibrillation can become life-threatening because of an increased risk of embolism due to altered blood flow patterns. Blood then flows particularly slowly in small extensions of the heart’s atria, called cardiac auricles, so blood clots (thrombi) are more likely to form there. The risk of stroke is increased fivefold.

Therapy of atrial fibrillation

Appropriate medications as part of therapy include:

  • Beta-blockers that slow the heart rate.
  • Calcium channel blockers (also known as calcium antagonists, for example, verapamil or diltiazem)
  • The rarely used cardiac glycosides (for example, digitoxin).

If necessary, a combination of these drugs may be used. These drugs aim to regulate the heart rate. In persistent atrial fibrillation, the heart rhythm can only be normalized by electric shocks (electric cardioversion).

Stroke prevention as part of treatment.

In addition, it is important to administer blood clotting agents as part of stroke prevention. Conventional anticoagulant medications, such as the vitamin K antagonists warfarin and phenprocoumon, require ongoing dose adjustment and laboratory monitoring. However, for people with mechanical heart valves, they are the only treatment option. Newer drugs from the group of active ingredients known as the new oral anticoagulants (anticoagulants) are considered first-line agents according to the guidelines, because they improve stroke prevention and do not have the disadvantages mentioned for patients with atrial fibrillation. These include dabigatran, which was approved in early 2011 – but it should be noted that the drug Pradaxa is unsuitable for people with kidney dysfunction.

Ablation by cardiac catheterization

If the aforementioned therapeutic methods are not sufficient, catheter ablation may be performed. Ablation by cardiac catheter involves obliterating the sites where the pulmonary veins join the atria. So that the normal rhythm is then maintained, so-called antiarrythmic drugs are used for subsequent treatment. In addition, even after acute atrial fibrillation has subsided, measures should be taken to permanently stabilize the heart rate and identify possible causes.