”Why do I have atrial fibrillation? What is the cause?”
This is one of the most frequently asked questions by patients with atrial fibrillation. However, it may not be possible to give a standard answer to this question, but we can only hope to provide some medical knowledge to patients through existing clinical analysis and observation ……
Atrial fibrillation is a very complex cardiac arrhythmia, and since the discovery of this electrophysiological phenomenon in 1874, the medical community has never stopped exploring the mechanism of its occurrence.
Therefore, there is no very definite answer to the etiology of atrial fibrillation, but through clinical analysis and observation, the correlation between atrial fibrillation and some diseases has been found.
I. Organic heart disease
1, rheumatic heart disease: about 33.7% of the causes of atrial fibrillation, with mitral stenosis and atretic insufficiency more common.
2, coronary artery disease: coronary angina confirmed by coronary angiography, the incidence of atrial fibrillation is 1.5%, the incidence of atrial fibrillation in old myocardial infarction is 3.8%; the incidence in acute myocardial infarction is 8.2%. In contrast, the incidence of atrial fibrillation was 11% in those with normal coronary arteries confirmed by coronary angiography for chest pain. In short, the incidence of coronary heart disease is low.
3, hypertensive heart disease: many small arterial lumens of its atrial muscle can be narrowed or completely occluded due to intimal thickening, causing local ischemic changes and fibrosis in the myocardium, which is closely related to the occurrence of atrial fibrillation.
4, hyperthyroidism: early myocardium has focal necrosis and lymphocyte infiltration, and the myocardium is often fine and limited fibrosis in those with a long course of disease, with an incidence of atrial fibrillation of 5%, mostly in patients aged 40 to 45. It is less common in young patients, and even if it occurs, it is mostly paroxysmal. Atrial fibrillation improves or disappears after thyroid function is restored.
5, pathological sinus node syndrome: when the sinus node artery focal myofibrillar structural dysplasia, collagen structural abnormalities and perisinus node degeneration, especially perisinus node degeneration and sinus impulse abnormalities, can contribute to the occurrence of atrial fibrillation.
6, cardiomyopathy: all types of cardiomyopathy, often because of focal atrial muscle inflammation, degeneration or fibrosis, atrial enlargement easily lead to the occurrence of atrial fibrillation, of which alcoholic cardiomyopathy patients atrial fibrillation is often the first manifestation of the disease, the incidence is high.
7, other heart disease: such as pulmonary heart disease, the incidence of atrial fibrillation is 4% to 5%, mostly paroxysmal, respiratory function will be reduced after the improvement of the attack; chronic constrictive pericarditis; congenital heart disease, etc.. Atrial fibrillation is a focal origin fibrillation with increased autoregulation; while some of the paroxysmal and some of the persistent and chronic atrial fibrillation is caused by intra-atrial, pulmonary vein and vena cava local microfold mechanism.
II. Preexcitation syndrome
The incidence of preexcitation complicated by atrial fibrillation is 11.5% to 39%. Preexcitation syndrome complicated by atrial fibrillation is considered serious because the bypass does not have the protective effect of physiological conduction delay like the AV node, so the ventricular rate of downward transmission via the bypass is mostly above 180 beats/min, which seriously affects the blood output of the heart. The mechanism for this is probably due to the short parasternal nonresponse period in patients with preexcitation syndrome. Once the foldback condition is established, the impulse through the parasternal pathway increases, and this impulse folds back into the left atrial stress period to induce atrial fibrillation.
Third, other diseases
1, systemic infiltrative diseases: systemic lupus erythematosus, scleroderma, leukemia, amyloidosis, etc.
2, pulmonary and systemic infections and chronic pulmonary insufficiency.
3, Cardiac surgery and trauma.
4, digitalis poisoning, aconitine, nicotine and other poisoning can induce atrial fibrillation.
5, various cardiac catheterization operations and transesophageal electrical stimulation, electrical resuscitation, etc. can directly induce atrial fibrillation.
6, alcoholism and smoking, emotional excitement, excessive smoking, urination, etc. can directly occur or induce atrial fibrillation on the basis of the original heart disease.
Fourth, familial atrial fibrillation
Atrial fibrillation is caused by genetic mutation, the mode of inheritance is AD, mostly occurs in adulthood, is paroxysmal, atrial fibrillation occurs and terminates unknowingly. The symptoms of atrial fibrillation attacks are mild, mostly triggered by exertion, mental stress, infection, pain, alcohol consumption, smoking, etc., and the cardiac function remains normal. The prognosis is generally good.
V. Unknown cause
Idiopathic atrial fibrillation occurs in healthy people, often without the basis of organic heart disease.
Atrial fibrillation has a complex pathogenesis, and its cause is like a fog. With the progress of medical technology and in-depth research, doctors will try to clear the fog and hope to give patients a final answer in the near future.
Six, how to identify atrial fibrillation?
The American Heart Rhythm Association has summarized six major signs of atrial fibrillation that can help you identify atrial fibrillation early.
The first is a thumping in the chest, as if thunder is rolling, drums are beating or fish are diving;
Secondly, the pulse is unequal in strength, and sometimes it feels like a missed beat;
Third, the feeling of shortness of breath when exerting;
Fourth, it is easy to fatigue, the amount of exercise is reduced;
Fifth, there is chest tightness (chest pain);
Sixth is the occurrence of fainting or dizziness symptoms.
Once these signals appear, patients should not be careless, indicating that atrial fibrillation may have occurred, should promptly seek medical treatment.
Seven, long-term alcohol abuse is a risk factor for atrial fibrillation
In recent years, the ranks of patients with atrial fibrillation have become increasingly large. Therefore, there is an urgent need for primary prevention of atrial fibrillation to stop its occurrence and development. For the prevention of atrial fibrillation, risk factors such as hypertension, myocardial ischemia, heart failure, acute infection and long-term alcohol consumption must be removed. In particular, experts warn that hypertension predisposes to atrial fibrillation, with 39 out of 100 hypertensive patients likely to develop atrial fibrillation. Patients with hypertension should pay attention to the control of blood pressure, if both hypertension and atrial fibrillation, the risk factor of stroke is very high.
Eight, a simple electrocardiogram can confirm the diagnosis of atrial fibrillation
Due to the loss of control of the sinus node of the heart in patients with atrial fibrillation, the contraction of the atria stops, causing the ventricles to beat rapidly and irregularly, up to 100-150 times, or even up to 200 times. Most patients with atrial fibrillation have symptoms such as panic, shortness of breath, chest tightness, irregular heartbeat and even fainting. Experts say that in the early stage of atrial fibrillation, patients feel obvious panic and their heartbeat is fast and slow, and the symptoms are very significant.