From the Guidelines
Atrial fibrillation (AF) is primarily caused by abnormal electrical signals in the heart, which can be induced by various factors, including certain drugs, particularly anticancer drugs, as evidenced by a recent review in Pharmacological Research 1. The main causes of AF include:
- Aging, which leads to changes in heart tissue, making it more susceptible to irregular electrical activity
- High blood pressure and heart disease, which create strain on the heart and disrupt normal electrical pathways
- Structural heart abnormalities, such as valve problems or heart failure, which can stretch the atria and override the heart's normal pacemaker
- Thyroid problems, excessive alcohol consumption, and sleep apnea, which can also contribute to AF development
- Certain drugs, including anticancer drugs, which can induce AF in patients with or without pre-existing cardiac disorders, as discussed in a 2024 study 1 The risk of drug-induced AF (DIAF) increases in elderly patients and those treated with polypharmacy, and it is essential for clinicians to be aware of the problem and recognize which drugs may cause DIAF. As people age, the heart tissue changes, and conditions like hypertension and coronary artery disease create strain on the heart, while other factors such as obesity, diabetes, and genetic predisposition can also contribute to AF development. The irregular electrical signals override the heart's normal pacemaker, causing the atria to quiver instead of contracting effectively, which can lead to blood clots, stroke, and heart failure if left untreated. Management typically involves medications to control heart rate or rhythm, blood thiners to prevent clots, and sometimes procedures like cardioversion or ablation to restore normal heart rhythm, as discussed in the context of DIAF treatment 1.
From the Research
Causes of Atrial Fibrillation (Af)
The causes of Atrial Fibrillation (Af) are complex and multifaceted. Some of the key factors that contribute to the development of Af include:
- Electrical and structural remodeling of the atria, which can be caused by conditions such as hypertension, congestive heart failure, and atrial stretch 2
- Atrial fibrillation itself can lead to electrical remodeling, but not structural remodeling 2
- Lifestyle factors such as age, sex, hypertension, diabetes mellitus, obesity, alcohol consumption, exercise, and obstructive sleep apnea can increase the risk of developing Af 3
- Autonomic imbalance, which can be caused by chronic stress, can act as a driving force behind the atrial ectopy and reentry that promote Af 4
- Cardiopulmonary, behavioral, and psychological risk factors can generate electrical and structural alterations of the atria that promote reentry and wavebreak, leading to Af 4
Risk Factors
Some of the key risk factors for Af include:
- Age: Af is more common in older adults 5
- Hypertension: High blood pressure can increase the risk of developing Af 2, 3
- Diabetes mellitus: Having diabetes can increase the risk of developing Af 3
- Obesity: Being overweight or obese can increase the risk of developing Af 3
- Alcohol consumption: Excessive alcohol consumption can increase the risk of developing Af 3
- Exercise: While regular exercise is important for overall health, excessive exercise can increase the risk of developing Af 3
- Obstructive sleep apnea: Having obstructive sleep apnea can increase the risk of developing Af 3
Pathophysiology
The pathophysiology of Af is complex and involves multiple factors, including: