Definition
A cardiac arrhythmia or arrhythmia of the heart is defined as a heartbeat that is too fast (tachyarrhythmia) or too slow (bradyarrhythmia) or the occurrence of additional “extra” heartbeats (extrasystoles). Extrasystoles can briefly bring the heart out of its normal rhythm. They are also described as heart stumbles and often have a frightening effect on the person affected.
Symptoms
The symptoms can be very different depending on the type of dysrhythmia. Extrasystoles are described as either stumbling or dropping out. They are unpleasant, but in most cases do not disturb the heart function.
If it is a tachycardic (too fast) arrhythmia, strong palpitations up to palpitations are described. In addition, chest pain, dizziness and shortness of breath may occur. In the case of a bradycardic (too slow) arrhythmia, dizziness, headache, nausea and unconsciousness may occur because the slow heartbeat means that too little oxygen reaches the brain.
Causes
There are many causes for rhythm disturbances. They are classified according to their origin in the heart. Rhythm disturbances can be caused by the atria and the sinus node or by the ventricles.
Cardiac arrhythmias that cause atria and sinus nodes are called supraventricular arrhythmias. The sinus node is the clock of the heart, it ensures a regular and orderly heartbeat. If it gets out of sync, the heart action is either too fast (tachycardia) or too slow (bradycardia), depending on the type of arrhythmia.
The most common supraventricular arrhythmia is atrial fibrillation, the atria beating disorderly and much too fast. This causes an absolute arrhythmia of the whole heart, the pulse is very irregular and fast. In addition, thrombi can form during atrial fibrillation, which can cause a stroke or pulmonary embolism.
Other causes can be an AV block. In this case the transition from the atrium to the chamber is not correct. The AV block is symptomatic of bradycardia.
In addition, there may be an additional conduction path between the atrium and the chamber, which disturbs the sinus rhythm. This is called Wolf-Parkinson-White syndrome. Rhythm disturbances originating from the ventricles are life-threatening and an urgent emergency.
If the heart flutters or fibrillates, there is no decent contraction anymore, a functional cardiac arrest is present. Apart from this, occasional extrasystoles may occur between normal sinus rhythms, which are perceived as “stumbling” or “dropping out”. Here, too, the ventricle becomes an irregular clock and disturbs the sinus rhythm. They are harmless in most cases, but should be clarified.