An overview of atrial fibrillation
Atrial fibrillation is categorized under tachyarrhythmias together with other arrhythmias like atrial flutter and supraventricular tachycardia. Before understanding what is atrial fibrillation, you have to first know in depth about the generation and conduction of electrical impulses in the heart that results in the pumping out of blood to the systemic circulation.
Our organ heart is divided into 4 rooms or chambers called as 2 atriums and 2 ventricles which contracts to pump the blood out from the heart to the cells and tissue of the body for organ perfusion. The sinoatrial node which is located at the junction of the right atrium will first generate electrical impulse to be sent to the walls of the atrium to contract and pump the blood to the chambers below which are the ventricles.
The electrical impulse is then conducted and sent to an atrioventricular node which is located in between two ventricles, it is then sent to the walls of ventricles through some small fibres along the septum and apex of the heart. This will eventually cause the muscular wall of the heart to pump out blood. Under abnormal circumstances, there will be more than one centrepoint that will start to generate electrical impulses causing the atrium wall to fibrillate rather than contracting. This condition is called atrial fibrillation.
Continue reading the article to know more about the multiple causes of atrial fibrillation and its common symptoms.
Causes of atrial fibrillation
Here are some of the most common causes of atrial fibrillation affecting any age group.
- Coronary artery disease
When you have a cut of blood supply due to formation of blood clot at coronary vessels, there will be muscle necrosis and death due to inadequate perfusion to the particular area. This can eventually alter the surface wall of atrium and leads to formation of more than one centrepoint which is able to generate electrical impulses.
- High blood pressure
Having high blood pressure will gradually force the heart to pump harder than usual, this can cause some alterations to the generation and conduction of electrical impulses. However, the exact pathophysiology is still unknown.
- Valvular heart disease
Having loose or too tight valves can cause enlargement of muscular walls around the heart. This change in anatomy can also alter the surface wall causing atrial fibrillation.
- Thyroid problems
Thyroid diseases like hyperthyroidism originating from Graves’ disease or thyroid cancer can increase body metabolic rate and heart rate causing the heart to pump blood even harder than usual causing hypertrophy of smooth muscles and atrial fibrillation.
- Exposure to stimulants
Exposure to stimulants like caffeine, medications, tobacco and alcohol can increase your heart rate temporarily and cause atrial fibrillation to occur.
Symptoms of atrial fibrillation
Not everyone with atrial fibrillation will manifest with similar signs and symptoms. This can vary depending on the type of atrial fibrillation you are having and other medical comorbidities. Here are some of the common symptoms felt by atrial fibrillation patients.
- Palpitations, which is a sensation of racing and irregular heartbeat.
- Reduced effort tolerance
- Chest pain and shortness of breath
- Lightheadedness and dizziness
Atrial fibrillation can be either permanent which in this case you will be requiring lifelong medications to prevent further progression of complications. In some cases, atrial fibrillation can be occasional where you have these symptoms for minutes to days and eventually goes off. In severe cases, your atrial fibrillation can be a long standing persistent when the symptoms persists for more than 12 months of your life and this condition will usually require heart medicines to control your heart rate and antiplatelet medication to prevent complications like stroke and peripheral vascular disease.