Atrial fibrillation | How can a stroke be prevented?

Atrial fibrillation

Atrial fibrillation is a cardiac dysrhythmia that can cause blood clots to form in the heart. These blood clots (thrombi) are then washed away with the bloodstream and block other smaller blood vessels (usually in the brain). If this happens in the brain, a stroke is the result.

The risk of developing atrial fibrillation increases with age. In people over 70 years of age, almost 10% are affected by the cardiac arrhythmia. Based on the individual risk profile of the patient, the doctor then decides whether blood thinning (anticoagulation) is necessary.

This protects patients with atrial fibrillation from a stroke. In many cases, the atrial fibrillation is only temporary (so-called paroxysmal atrial fibrillation). The heart always returns to the correct rhythm.

This can often make diagnosis difficult. It is not visible in the standard resting ECG. In most cases, a 24-hour long-term ECG is then performed.

This increases the chances of detecting any rhythm disturbances. Some patients are completely symptom-free despite atrial fibrillation. However, if the dysrhythmia is not detected and the patient is not treated with a blood thinner, the risk of stroke increases. For this reason, patients in old age should consult their family doctor regularly (1x per year) for a routine ECG checkup.

Blood Dilution

As already mentioned, blood thinning can reduce the risk of stroke. When taking blood-thinning medication, blood clots can no longer form so easily in the heart, even in cases of atrial fibrillation. If, in addition to atrial fibrillation, there are other risk factors for a stroke, such as age over 65 years, a stroke that has already occurred, high blood pressure, diabetes or coronary heart disease, thinning of the blood is strongly recommended.

This blood-thinning effect can be achieved by taking so-called vitamin K antagonists (most prominent example Marcumar®). Newer oral anticoagulants (blood thinners, abbreviated NOAK) such as Xarelto® or Eliquis® are also used. You can read more about this topic here: Blood thinnerASS or acetylsalicylic acid is also known to many under the trade name Aspirin® and also has a blood-thinning effect.

However, it is no longer used to prevent strokes in atrial fibrillation. Numerous studies have clearly shown that bleeding complications are just as frequent and serious as with vitamin K antagonists (e.g. Marcumar®). However, the number of strokes prevented was significantly lower. Nevertheless, ASA is still frequently used in medicine to thin the blood. For example, it is used after a heart attack or in cases of narrowing of the carotid artery (carotid stenosis).