Arrhythmia represents a deviation from normal heart rhythm. This means that the heart contracts irregularly. The heart is capable of automatism, which means that it is capable of producing contractions that we cannot physically control. A cluster of cells that produce electrical signals are located in the right atrium and are called the sinoatrial node. They send signals to other cells forming the heart muscle, which react to this irritation by contracting. This whole mechanism is carefully regulated. The heart is able to change the frequency of its contractions and with it, the amount of blood that is expelled. However, sometimes the process that creates regular electrical activity fails. In this case we speak of arrhythmia, a heart rhythm disorder.
Causes of Arrhythmia
The causes of arrhythmia are diverse. Arrhythmia arises from an enlarged heart during untreated hypertension (high blood pressure) as well as with abnormalities in the amount of minerals in the blood, the effects of stress, inflammation of the myocardium, the use of certain medications, poisoning, etc. Sometimes the cause of arrhythmia is not known. Certain types of arrhythmia and the predisposition to their formation can be inherited. All cases have one thing in common and that is that they affect of the heart's system of electrical signal formation.
Types of Arrhythmias
Arrhythmias can be classified according to various criteria. If they are divided according to the section of the heart that is affected, then there are three types of arrhythmia: atrial, supraventricular and ventricular. Arrhythmias can also be divided according to their mechanism of development, i.e. the malfunction of the formation or the malfunction of the conduction of the electrical signals. Sometimes there is a combination of both. The third option how to classify arrhythmias is according to its frequency, i.e. bradycardia, heart rhythm disorder causing a decreased heart rate, and tachycardia, which causes an increased heart rate.
Atrial arrhythmias are such that the cause of the arrhythmia occurs in the atria. Atrial arrhythmias include atrial fibrillation, atrial flutter, and atrial extrasystole.
- Atrial fibrillation means rapid and disorganized contractions of the cells in the atrium. This leads to quivering of the atria and not to their contraction. This results in the incomplete filing of the ventricles and accumulation of blood in the atria, which can clot and develop a thrombus. This type of arrhythmia develops from valvular disorders and acute myocardial infarction. It is manifested by chest pain, fatigue and shortness of breath. Treatment consists of the administration of antiarrhythmics and if this is unsuccessful, an electrical cardioversion is performed where with the help of a device, the heart's natural rhythm is returned.
- Atrial flutter means the fluttering or quivering of the atria, i.e. rapid contractions of the muscle cells of the atria caused by the presence of an area with increased activity. This sends signals for rapid contractions of the atria. Atrial flutter is manifested by heart palpitations and can last from a number of seconds to a few days. Other symptoms can include dizziness and chest pain. Treatment of this type of arrhythmia is the administration of antiarrhythmics.
- Atrial extrasystole is one of the most common abnormalities. It is the addition of an atrial contraction beyond the heart's normal rhythm. This additional contraction can occur in the sionatrial node or outside it. Clinical manifestations are not particularly pronounced.
Ventricular arrhythmias are arrhythmias of the ventricles. They can also cause an increased or decreased heart rate. The most common ventricular arrhythmias include ventricular tachycardia, ventricular extrasystole and ventricular fibrillation.
- Ventricular tachycardia is an increased heart rate originating in the ventricles. This typically occurs in patients with cardiomyopathy, following a heart attack or with an ion imbalance. The ventricles contract irregularly, which can result in insufficient blood supply, especially to the brain, leading to loss of consciousness. Other symptoms include shortness of breath and heart palpitations. Treatment of ventricular tachycardia relies on an electrical cardioversion.
- Ventricular fibrillation is the irregular and chaotic contractions of the ventricles, leading to ineffective contractions and therefore blood is not pumped from the left ventricle into the body. This type of arrhythmia is life-threatening. If ventricular fibrillation is not interrupted with a cardioversion within 3 to 5 minutes, the patient will die of irreversible brain damage.
- Ventricular extrasystole is the addition of a contraction originating in the ventricles or in the lower part of the cardiac conduction system, which under normal circumstances conducts impulses from the atria to the ventricles. These arrhythmias can occur in healthy individuals. Ventricular extrasystole is often asymptomatic but can be manifested by heart palpitations, chest pain and loss of consciousness. Treatment of ventricular extrasystole includes antiarrhythmics and in the event that these medications are unsuccessful, surgical removal of the area that causes abnormal contractions is necessary. Some patients require a defibrillator to be implanted after successful treatment.
Consequences of Arrhythmia
Consequences of arrhythmia depend on its types. Some are asymptomatic and occur in healthy individuals, such as atrial axtrasystole. The most severe and life-threatening are ventricular fibrillation, when the heart is not able to effectively contract and pump blood into the body. Certain arrhythmias, such as atrial fibrillation, causes blood flow to slow down and can lead to the formation of a blood clot (thrombus). This thrombus can subsequently travel into the lungs and cause a pulmonary embolism, which is usually a fatal complication. The blood clot can also travel through the blood stream into the brain, resulting in a stroke.
First Aid for Arrhythmia
Arrhythmia should be considered a possibility if a patient complains of chest pain, shortness of breath and heart palpitations. Arrhythmias are often the cause of loss of consciousness. In the case of cardiac arrest and loss of consciousness, first aid in the form of a heart massage should be provided. Because this can be a very dangerous condition, medical help must be provided as soon as possible. In the event that problems suddenly occurs and then disappear, a visit to the doctor is recommended. Proper testing can help prevent further problems.