Atrial fibrillation is the most common abnormal rhythm of the heart. It is the most implicated causative factor among people who have suffered a stroke. Yet, many of us might have it without knowing. So, you might want to check your heart.
The speed and pattern of the heartbeat generate a heart rhythm, and we ascertain its nature by feeling the pulse. We can check the heartbeat over the left anterior chest wall by auscultation. We can also do in the neck (carotid pulse), arm (brachial pulse), on the forearms near the wrists (radial pulse), the groove at the back of your knees (popliteal pulse), behind your ankles on the inside (posterior tibial pulse), and the dorsum of the foot near the big toe (dorsalis pedis pulse).
The signals from the electrical system of the heart set up the heart rhythm. We can feel it like a pulse or pick it up on an electrocardiogram. If the rhythm is abnormal, we call it an arrhythmia. Several cardiac arrhythmias exist, and atrial fibrillation is one of them.
Remember that the electrical activity that drives the heart muscle to contract is initiated from the right atrium by a few specialised cells. The right atrium is one of the four chambers of the heart – two atria and two ventricles. The right atrium receives deoxygenated blood from the rest of the body (excluding the lungs) and allows it to flow down to the right ventricle. The ventricle then contracts following appropriate electrical signalling to pump blood to the lungs for oxygenation. Oxygenated blood from the lungs returns to the heart into the left atrium. The left atrium then allows it to flow into the left ventricle, which pumps it to the rest of the body, and the cycle continues. So, in one heartbeat, blood circulates the body in what we call a cardiac cycle.
The specialised cells that initiate an electrical signal within the right atrium may malfunction and send more of them than expected. It implies that the atrium will contract very quickly with asynchrony. The result may be that small, irregular, fast contractions occur within the atrium, and at this juncture, fibrillation occurs. And the atria do not pump all the blood into the ventricles, so the remaining blood stagnates. Stagnated blood has a greater propensity to clot. Once clots form, they may dislodge, enter the ventricles, which may pump them either to the lungs or brain – to cause pulmonary embolism or stroke, respectively. In another scenario, blood mixed with clots is thicker than usual, so the ventricles work harder to move it to the various body parts. In the end, they may fail, and heart failure ensues.
Ageing is the most recognisable cause of atrial fibrillation; however, several others are worth mentioning. They include congenital heart disease, hypertension, congestive heart failure, valvular heart disease, coronary artery disease, myocardial infarction, alcohol abuse: diabetes, hyperthyroidism, pheochromocytoma: obstructive sleep apnoea: myocarditis, pericarditis, and a few genetic factors. It’s noteworthy that atrial fibrillation can develop in any condition that leads to ischaemia, damage, stress, or inflammation that targets the heart musculature, for example, taking too much caffeine.
In most cases, you may have atrial fibrillation without noticing it because it may be asymptomatic. However, you may have symptoms due to the disorder, such as palpitations (very fast heartbeats), irregular pulsations, difficulty breathing, chest pain, fainting, or you tire easily or cannot do your routine exercises. Once you develop any, you will need to check-in at the nearest hospital to undergo extensive evaluation.
We diagnose atrial fibrillation by looking at a particular pattern of waves on an electrocardiogram. We will then check the movements of the atria using an echocardiogram. If your atrial fibrillation is not persistent, we may attach a portable monitor to record your rhythm in 24 hours (Holter ECG).
For atrial fibrillation management, we treat the cause. An example, lessening alcohol consumption, treating hyperthyroidism, and treating congestive heart failure.
The crucial aspect is to control your heart rhythm. We can achieve this through a class of drugs called anti-arrhythmic drugs. They slow down the heart rate and make it regular. In a few instances, the atrial fibrillation may resolve without medications.
Clot formation is the most common complication of atrial fibrillation. So, we will give you blood thinners (anticoagulants) such as heparin and rivaroxaban to prevent clots from forming. All these drugs require monitoring. You may have several appointments for follow-up.
For some patients, the drugs either fail to avert the arrhythmia or aren’t suitable. So, they undergo cardioversion, cardiac surgery to destroy the part of the heart generating the abnormal signals or place a pacemaker. The type of treatment depends on the nature of the atrial fibrillation and its cause.
To prevent or live with atrial fibrillation under control, you will embark on a heart-healthy diet, keep an ideal weight, reduce stress: exercise as much as you can, take medications as prescribed, and call your doctor as soon as you develop new or worsening symptoms, such as dizziness, chest pain or heaviness, fainting, and shortness of breath. Remember to avoid activities that increase the risk of bleeding if you are taking blood thinners. Do not use tobacco, and curb down on the amount of alcohol or caffeine you consume.