Atrial fibrillation (AFib) is the beating of the heart in an abnormal manner. The pathology lies in the conduction of electrical impulses in the atrial tissue.
This abnormal rhythm (Afib) can generate a lot of problems in the pumping of blood through the heart and can have very serious outcomes.
Atrial fibrillation develops in the heart, usually due to unresolved atrial flutters and extrasystoles. It exists when the atrial tissues send impulses at a rate of 250 beats/minute or higher, resulting in irregular fibrillation waves in the electrocardiogram (ECG / EKG) graph.
ECG / EKG Patterns in Atrial Fibrillation
A normal heart pumps blood with the atria and ventricles contracting and relaxing, this generates an ECG / EKG pattern. This pattern can be used to differentiate between the normal conductivity of the heart and one with underlying pathology.
Impulse is generated by the SA node, which shows automaticity. Then this impulse travels forward to help the muscles of the atria and ventricles to contract. If any other part of the atrial tissue obtains automaticity, it starts firing abnormal impulses, disturbing the normal conduction, and compromising the pumping activity of the heart. These abnormal impulses are generated from specific areas that get formed inside the atria, known as ‘ectopic foci’.
When the atrial tissue contracts, a P wave is generated in the electrocardiogram (ECG / EKG) followed by a QRS complex, which represents the contraction of the ventricular musculature. Any abnormalities in the atrial tissue results in a deformed P wave.
When the atrial tissue generates a rapid but disorganized signal, it disturbs the whole cycle of the heart. These frequent discharges result in a delay for the muscles of the heart to fully relax. This causes a few changes in the ECG / EKG wave pattern. The P wave either appears in spikes or appears a lot sooner than a normal sinus P wave is supposed to occur with a shorter QRS complex.
Signs and Symptoms of a Person With AFib
Atrial fibrillation is a condition that does not get diagnosed earlier due to its ambiguous symptoms. Most often, it is missed due to minor changes in the electrocardiogram.
- Some people remain asymptomatic and do not experience any kind of change. Except when it progresses to an extent that it disturbs their normal routine.
- Whereas for others, palpitations, shortness of breath, chest pain, stress during exercise, feelings of lightheadedness are some of the common symptoms.
- In more severe cases, patients of atrial fibrillation also suffer from swelling of legs and start showing symptoms of congestive cardiac failure.
All of these symptoms arise due to ineffective pumping of the heart. Leading not just to ischemia of various organs but also triggers infarction and strokes.
Causes of Atrial Fibrillation
A number of reasons have been seen to attribute the risk of having atrial fibrillations.
- Obesity has been greatly linked with all kinds of heart diseases and atrial fibrillation is one of them. It increases the risk of hypertension, which is a major risk of clot formation as well as fibrosis in the walls of the heart. Fibrosis results in the formation of ectopic foci and that directly produces ectopic impulses.
- Increasing age is also an important risk factor. Because as a person ages, the number of inflammatory processes increases two-fold, due to excessive breakdown, which precipitates AFib.
- Genetics also has a big role to play. It is estimated that people with a positive family history of atrial fibrillations are at an increased risk of 40% of acquiring it. Because mutations in genes result in abnormal atrial remodeling because of which atrial fibrillations become persistent.
- People who are avid smokers or use other tobacco products are also associated to be at risk. It not only increases oxygen demand for the heart but also is responsible for narrowing arteries increasing the incidence of stroke.
A Cellular Mechanism that Results in AFib
The main etiology that is responsible for the production of atrial fibrillations, is due to the drivers that maintain it. These ‘drivers’ are either due to reentry circuits or ectopic focal impulse generation.
These irregular ectopic impulses can be due to either of the three following reasons:
- Local ectopic firing.
- Due to a localized reentry circuit.
- Multiple reentry circuits randomly present, causing fibrillatory activity.
Atrial fibrillation presents clinically in various forms. It is presumably believed to start off as the paroxysmal type, which may become persistent and then permanent with time. These forms develop due to structural and functional remodeling occurring in the atrial tissue, due to atrial tachyarrhythmias or some underlying disease of the heart.
Ectopic foci get formed inside the walls of the atria due to three main reasons. Firstly, due to structural remodeling (fibrosis). Secondly, due to electric remodeling (high levels of calcium entering the muscle of the heart, disturbing the ion balance). And thirdly, due to metabolic remodeling (high levels of lactate, promoting atrial remodeling).
How to Manage Atrial Fibrillation?
The management of atrial fibrillation depends on three noticeable factors;
- Rate control.
- Rhythm control.
- Prevention of thromboembolism.
Pharmacological therapy with antiarrhythmics has not proved to be very promising, as its long-term usage aggravates the arrhythmias. Therefore, people with no underlying cardiac conditions are given anticoagulants. It is done to help the heart pump blood effectively without any clot formation.
However, it also increases the risk of bleeding, so it cannot be given to someone with an underlying heart condition.
A meta-analysis conducted in Canada, proved magnesium to be effective in controlling rate as well as rhythm in cases of atrial fibrillations. This makes it probably the best choice to be used in patients of AFib. Other medications used in order to control the rate are beta-blockers, cardiac glycosides (digoxin), as well as verapamil and diltiazem. However, excessive use of digoxin can result in premature ventricular complex formation due to its toxicity.
Another way of managing AFib is cardioversion therapy. It is a technique used to restore normal cardiac rhythm by either electrical or chemical means.
Lastly a surgical procedure; radiofrequency catheter ablation is another way to help manage atrial fibrillations. This procedure can only be advised to people with no existing heart conditions. The process directs all ectopic impulses of the atria towards the ventricles and hence restores the normal rhythm of the heart. However, patients undergoing this procedure require a pacemaker afterward.
Manage Your Heart Using ECG / EKG Reading Device
The best way to prevent atrial fibrillations is to detect in its earliest stages. The key is regular heart monitoring with the help of an electrocardiogram. This solution within a simple, fast and effective heart measurements detects signs of existing or potential AFib risks. Thereby allowing you to act in order to prevent them before it is too late.
People with underlying heart conditions like ischemic heart disease, myocarditis, rheumatic heart disease should be on the lookout of this condition. Also, people with other metabolic disorders as hyperthyroidism, diabetes mellitus, and hypertension, should be screened so it does not progress drastically.
To sum it all up, atrial fibrillations are due to a defect in the conduction of impulses of the heart. The diagnosis of this condition is very uncertain, many doctors miss the minute changes in the ECG / EKG causing AFib. This leads to its progression becoming very dangerous for the person suffering from it. Some of the common symptoms include dizziness, feelings of anxiety, palpitations as well as breathlessness.
Genetics, obesity, hypertension, diabetes, endocrine disorders all act as predisposing factors. Hence, people with any of these conditions should always stay aware and get themselves screened if they experience any of the mentioned symptoms.
Not many medicines have shown efficacy in treating atrial fibrillations completely. Thereby surgery becomes the most effective management strategy in this regard. However, the infusion of magnesium has shown great results in trials and might help treat AFib completely.