Cardiac arrhythmias - irregular heartbeat
- The heartbeat - a complex interplay of forces
- Irregular heartbeat - a heart rhythm disorder
- Classification of cardiac arrhythmias
- Irregular heartbeat (pulse) is often normal
- Atrial fibrillation and atrial flutter
The heartbeat - a complex interplay of forcesThe electrical conduction system in the heart causes the heart muscle fibers to contract. In addition to the fact that the heart rate is controlled by the autonomic nervous system, such as the vagus nerve (heart rate delay), the symphaticus and the parasympathicus, every heartbeat arises in the sinus node located in the upper right wall of the atrium. In addition, every stimulus runs meticulously through specific lanes and at a regulated speed through the heart muscle (atria). The heart rate depends on the speed at which the sinus node fires, influenced by the nervous system but also by the endocrine system.
Normal ECG heart rate / Source: Blausen Medical Communications, Inc., Wikimedia Commons (CC BY-3.0)ECG
From the bosoms the conduction stimuli led to the atrioventricular node (AV node) and then to the chambers (ventricles) via the bundle of His and the bundle branches. In other words, a 'beating heart' is a complex interplay of forces. In addition to the heartbeat responding to exertion, emotions and stress, disorders may develop that are accompanied by a too high or low heart rate, an irregular heartbeat or an abnormal conduction path along which the electrical impulses move through the heart. The latter is incidentally only visible on it ecg.
Irregular heartbeat - a heart rhythm disorderIn many cases, an irregular pulse is due to some or more extra beats the heart makes. This is called 'extrasyst oil'. It feels like pounding in the chest or throat, but some also experience it as pain or a pressure sensation in the chest.
Classification of cardiac arrhythmiasThe most common arrhythmias that may or may not be accompanied by an irregular heartbeat are:
- Tachycardia. Abnormally high heart rate of more than 100 beats / minute.
- Bradycardia. Very slow heart rhythm of less than 50 beats / minute.
- Irregular pulse. This may indicate atrial fibrillation / flutter, extrasystoles or other conduction disorders.
- Extrasystoles. These so-called transshipment occur sporadically with everyone.
- Atrial fibrillationNumerous very weak conduction stimuli in the muscular tissue of the atria (asria), as it were, hold the sinus node, causing the anterior chambers to fibrillate. With atrial fibrillation, a so-called supraventricular arrhythmia, the heartbeat is always irregular and uneven.
- Bosom flutter. Irregular pulse circuit in the atria (atria). Atrial fibrillation and atrial flutter are related to each other, their treatment is also the same.
- Adams-Stokes syndrome. Various dysrhythmias, including ventricular fibrillation, can cause unconsciousness attacks, among other things.
- Heart block. Conductivity restriction in the anterior chambers (atria), ventricles (ventricles), the atrioventricular node or in the bundle of His (bundle branch block).
Irregular heartbeat (pulse) is often normalAn irregular heartbeat is often a sign of an underlying heart rhythm disorder, ranging from atrial fibrillation to sinus node dysfunction (sick sinus syndrome). Nevertheless, a somewhat irregular heartbeat is normal. This is a physiological irregularity that is associated with breathing, corresponds to it, and does not 'traverse' the inhalation and exhalation. In other words: the heart beats somewhat slower during the exhalation and a slight acceleration occurs during inhalation. People call that one respiratory arrhythmia.
Atrial or atrial fibrillation / Source: J. Heuser, Wikimedia Commons (CC BY-SA-3.0)
PalpitationsIf an irregular pulse is accompanied by heart pounding, or heart palpitations, extrasystolia is usually present. This can have many causes, ranging from nervousness, agitation and effort to certain medication use (side effects). On the other hand, many arrhythmias due to conduction problems have an irregular heartbeat in their wake. Below are two common causes.
Atrial fibrillation and atrial flutterAtrial fibrillation causes an irregular heartbeat, whereby the filling of the chambers (ventricles) is also uneven. With this arrhythmia, the bosoms cannot normally contract due to very rapid discharges outside the sinus node, which causes the atria to end up in a kind of spasm, vibrate (fibrillate) and can no longer contract efficiently. The Aschoff-Tawara node (atrioventricular node) only irregularly transmits a few impulses to the chambers. Due to the reduced useful effect of cardiac action in atrial fibrillation, cordial heart failure is always lurking.
Atrial fibrillation can pass spontaneously, which is called paroxysmal atrial fibrillation, but often chemical (such as flecainide) or electrical cardioversion (defibrillate). The underlying causes of atrial fibrillation include heart valve defects, coronary sclerosis and dilation of the atria (dilatation). Due to the poor pumping function of the heart, clots can occur in the heart ear in particular, especially when the sinus rhythm recovers. Anticoagulation is therefore part of the treatment. Atrial flutter is closely related to atrial fibrillation. This involves an irregular conductor circuit. The heart rate is very high, with the ECG showing a sawtooth configuration. There is also usually a 2: 1 AV block. The treatment is identical to atrial fibrillation.
Extrasystolen / Source: Kalumet, Wikimedia Commons (CC BY-SA-3.0)
ExtrasystolesAn extrasystole is a heartbeat that comes too early, or a premature contraction of the chambers (ventricular), which can also take place in the atria (supraventricular), often before atrial fibrillation. A sporadic extrasystole as such is not a disease phenomenon and may be considered normal. As a result of a different electrical stimulus in the room muscle tissue, a premature room contraction occurs. Characteristic is the compensatory break where after each extrasystole a longer break follows where the heart is filled more strongly than normal. As if the heart stood still for a moment. The subsequent thump occurs because the heart pushes an extra large volume of blood through the aorta. Extrasystoles can disrupt the normal heart rhythm. This can be accompanied by all kinds of complaints, such as feeling restless and dizzy. Sometimes an extrasystole follows after each heartbeat, which is called bigeminie (twin heartbeat).
CausesExtrasystoles occur more often in old age, but also as a result of stress, alcohol, caffeine, smoking and certain medicines, such as some nasal drops (ephedrine). Common extrasystoles can occur as palpitations or heart thumping. Less innocent causes of extrasystoles include:
- Coronary sclerosis (calcification of the coronary arteries).
- Heart failure (congestive heart failure).
- Atrial fibrillation and flutter.
- During or (shortly) after a heart attack.
- Heart valve defects and ventricular dilatation (dilation of usually the left atrium).
- Wolff-Parkinson-White syndrome.