Understanding Atrial Fibrillation: Causes, Risks, and Consequences
What is Atrial Fibrillation? Atrial fibrillation, often referred to as AFib or AF, is a condition characterised by an irregular or quivering heartbeat. This arrhythmia can result in significant complications, including blood clots, strokes, heart failure, and other cardiovascular issues. It is a growing concern, with projections suggesting that by 2030, over 12 million people will be affected by this condition.
Patients with AFib describe a variety of experiences, such as a sensation of the heart flip-flopping, skipping beats, or pounding forcefully against the chest, particularly during physical exertion. Others report feeling nauseous, light-headed, and weak, with a rapid heartbeat and shortness of breath. Interestingly, some individuals may have no noticeable symptoms, only discovering the condition during a routine medical examination.
What Happens During AFib? Under normal circumstances, the heart beats in a steady rhythm, with its upper chambers (the atria) contracting and relaxing in sync with the lower chambers (the ventricles). In AFib, however, the atria beat irregularly and fail to pump sufficient blood into the ventricles. This inadequate pumping can cause blood to pool within the atria, increasing the risk of clot formation. If a clot is pumped out of the heart and reaches the brain, it can block an artery, leading to a stroke. Approximately 15% to 20% of strokes are attributed to this condition, which is why blood thinners are often prescribed to those with AFib.
If left untreated, AFib doubles the risk of death from heart-related causes and increases the likelihood of stroke fivefold. Despite these dangers, many people remain unaware of the severity of AFib.
Why is Atrial Fibrillation So Important? While an AFib episode itself might not be immediately life-threatening, the condition significantly raises the risk of stroke, even in the absence of noticeable symptoms. The root causes of AFib are not always clear, but it is often linked to damage in the heart's electrical system, which may result from longstanding high blood pressure, coronary artery disease, or complications following surgery.
AFib can lead to serious health issues, including heart failure, chronic fatigue, additional heart rhythm disorders, and inconsistent blood supply. Understanding the relationship between AFib, high blood pressure, and stroke is crucial for effective management.
How Does AFib Cause Strokes and Heart Failure? During AFib, the heart's upper chambers (atria) beat erratically, failing to effectively pump blood into the ventricles. This ineffective contraction can be likened to trying to wring water from a sponge without squeezing it properly—some water remains trapped inside. Similarly, when the heart’s contractions are weak or disorganised, blood may pool in the atria, heightening the risk of clot formation. If such a clot travels to the brain, it can cause a stroke, known as an embolic or cardioembolic stroke.
AFib can also lead to heart failure, as the heart may beat too quickly to allow adequate blood flow to the body. This rapid and inefficient pumping can cause blood to back up into the pulmonary veins, leading to fluid accumulation in the lungs and other symptoms such as fatigue, shortness of breath, and swelling in the lower extremities.
AFib and Additional Heart Rhythm Problems AFib disrupts the heart's electrical system, which ordinarily maintains a regular heartbeat. Normally, the heart's electrical impulses originate in the sinoatrial (SA) node, located in the right atrium, and travel to the atrioventricular (AV) node, which coordinates the timing of the heart's contractions. In AFib, these impulses may start erratically elsewhere in the atria or pulmonary veins, leading to rapid, disorganised contractions. The AV node struggles to manage these chaotic signals, often resulting in the ventricles beating too frequently, causing symptoms such as breathlessness and fatigue.
Can AFib Resolve on Its Own? While rare, spontaneous remission of AFib can occur. Nonetheless, even in cases where symptoms are not evident, the risks associated with AFib persist, making ongoing monitoring essential. AFib episodes may be brief and resolve on their own, or they may become persistent or even permanent, necessitating treatment.
Are You at Risk for Atrial Fibrillation? AFib can affect anyone, though certain factors increase the risk. Age is a significant factor, as the likelihood of developing AFib rises with advancing years. Other risk factors include longstanding high blood pressure, underlying heart conditions, a history of heart surgery, excessive alcohol consumption, a family history of AFib, sleep apnea, and certain chronic conditions like hyperthyroidism and diabetes. Athletes may also be at risk due to the strain on their hearts from intense physical activity.
Symptoms and Types of AFib AFib symptoms vary, with some individuals experiencing a fluttering or thumping sensation in the chest, while others may feel fatigued, dizzy, or short of breath. AFib can be classified into different types: paroxysmal, persistent, longstanding, and permanent. These classifications are based on the duration of episodes and the underlying causes. Paroxysmal AFib episodes may resolve on their own, while persistent AFib requires treatment to restore normal rhythm. Longstanding and permanent AFib are more chronic forms of the condition.
Heart Attack vs. AFib Symptoms While both heart attacks and AFib can involve chest discomfort, AFib is more associated with palpitations and fluttering sensations, whereas heart attacks often involve severe chest pain and other symptoms such as shortness of breath, cold sweats, and nausea. It is crucial for individuals with AFib to recognise the warning signs of a heart attack or stroke and seek immediate medical attention if these occur.
Conclusion Atrial fibrillation is a serious condition with potentially life-threatening complications, including stroke and heart failure. While some people may experience minimal or no symptoms, the risks associated with AFib necessitate vigilant monitoring and treatment. Understanding the causes, risks, and warning signs of AFib is vital for managing the condition and reducing the likelihood of severe outcomes.
Thanks to the American Heart Association
ZIVE can detect atrial fibrillation and help manage the effectiveness of treatment.