What Is an Atrial Fibrillation Pacemaker?

Persistent atrial fibrillation can be the first manifestation of arrhythmia, or it can progress from recurrent paroxysmal atrial fibrillation to persistent atrial fibrillation. Atrial fibrillation lasting more than 7 days.

Chinese name: Persistent atrial fibrillation

Department: Cardiology

Overview of persistent atrial fibrillation :

Atrial fibrillation (AF) is the most common cardiac disorder in the clinic. Uncoordinated atrial activity in patients with atrial fibrillation can lead to the decline of the atrial mechanism and ultimately to stroke and mortality. Atrial fibrillation can be subdivided into 3 types: paroxysmal AF, persistent AF, and permanent AF.

Persistent AF symptoms

Persistent atrial fibrillation is called persistent atrial fibrillation if the seizure persists for more than 48 hours and fails to revert on its own. Patients with atrial fibrillation feel palpitations and shortness of breath, especially after activity, the ventricular rate increases significantly. People with persistent AF are prone to heart failure. During atrial fibrillation, due to the lack of atrial contraction and hemodynamic disturbances, mural thrombosis is likely to occur, leading to systemic and pulmonary circulation embolism, of which cerebral embolism and limb arterial embolism are more common.

Causes of persistent AF and common diseases

Persistent atrial fibrillation is no longer just a disorder of the electrical activity of the heart. It is often accompanied by abnormal cardiac structures, such as cardiac muscle cells, extracellular matrix, microvascular changes, and endothelial cell remodeling. Moreover, the occurrence and development of atrial fibrillation are related to multiple risk factors such as genetic abnormalities, physiological age, gender, structural heart disease, arrhythmia, other system diseases such as diabetes, tumors, obesity, surgery and substance abuse addiction. Atrial fibrillation loses atrial systolic function, ventricular filling is incomplete, and cardiac output is significantly reduced. Long-term heart rate increase can lead to myocardial ischemia, heart failure, and tachycardia, increasing mortality by 2 times that of normal people. Loss of systolic function, blood is easily stagnated in the atrium to form a thrombus. After the thrombus falls off, it can follow the blood to the whole body, leading to cerebral embolism stroke, severe arterial embolism, and even amputation.

Differential diagnosis of persistent AF

Persistent atrial fibrillation itself is not a fatal arrhythmia, but it can cause discomfort such as dizziness and palpitations, and severely cause clinical diseases such as stroke, myocardial infarction, and heart failure.

During the onset of persistent atrial fibrillation, cardiac output is reduced by 25% to 30%, and patients may experience palpitations, chest tightness, and even syncope.

Atrial fibrillation can be initially diagnosed based on clinical symptoms and signs, but the ECG examination is needed to confirm the diagnosis. It is simple and easy, but the authors cannot capture the typical ECG for transient episodes of AF. Dynamic ECG monitoring is needed. For patients with AF, a cardiac ultrasound is also required Check for the presence of underlying heart disease.

Typical atrial fibrillation waves in ECG can be distinguished from supraventricular tachycardia or atrial flutter with irregular conduction blocks. With atrial fibrillation with complete bundle branch block or preexcitation syndrome, the ECG performance can closely resemble ventricular tachycardia. Careful identification of the obvious irregularities of atrial fibrillation and ventricular rhythm is helpful for the diagnosis of AF.

Continuous atrial fibrillation

Electrocardiogram and echocardiography are the most commonly used and specific tests for diagnosing atrial fibrillation and its etiology.

Continuous AF

Treatment of persistent atrial fibrillation involves managing its cause. Like hyperthyroidism, hyperthyroidism can cause persistent atrial fibrillation, so treating hyperthyroidism is helpful for the treatment of persistent atrial fibrillation. Followed by control of ventricular rate, reconstruction of sinus heart rate and prevention of embolism. Ventricular rate can usually be controlled with digoxin. Digoxin can increase the delay and block of atrioventricular conduction. If digoxin alone is not effective enough, -blockers or calcium antagonists [thiazepine, Verapamil (Varidium) is mostly effective.

Treatment of persistent AF also includes direct current shock. Because of a small number of patients with persistent atrial fibrillation, Ia or Ic antiarrhythmic drugs or amiodarone can be converted to sinus rhythm. At this time, DC electrocardiogram is the best treatment strategy. Before selective cardioversion, if persistent atrial fibrillation has lasted for more than 48 hours, anticoagulants should be taken for more than 3 weeks to reduce the risk of embolism. Through two electrode plates in front of and behind the chest, 100 to 400 watts of direct current was used for cardioversion. The longer the duration of atrial fibrillation (especially> 6 months), the larger the atrium and the more serious the heart disease, the lower the success rate of cardioversion. If there is no change in heart disease after cardioversion, the recurrence rate of AF is high. Although quinidine and procainamide are still widely used to maintain sinus rhythm, there is no data to show that the above drugs can prevent the recurrence of atrial fibrillation after cardioversion. Diisopramine, amiodarone, and Ic drugs may be more effective, but the advantages and disadvantages vary from patient to patient and should be considered.

Occasionally, the rate of atrial fibrillation is fast, and medication is ineffective. Radiofrequency can be used for atrioventricular node ablation to block atrioventricular node conduction, which may require the implantation of a permanent pacemaker. This treatment of persistent atrial fibrillation can benefit patients with impaired left ventricular function. Atrial fibrillation rate can be controlled by ablating lesions in the atrioventricular node input with selective radiofrequency catheters. 75% were successful without the need to install a permanent pacemaker. If this technique fails, resulting in complete atrioventricular block, a pacemaker needs to be installed.

Patients with left atrial enlargement and mitral valve disease are at greatest risk of systemic embolism due to persistent atrial fibrillation. However, all patients with persistent AF should consider long-term anticoagulation with warfarin. This is based on controlled trials suggesting a reduction in morbidity and mortality [maintaining prothrombin time between considerable international normalization ratio (INR) 2 to 3. So this is also one of the treatments for persistent AF.

Principles of persistent AF treatment

The purpose of AF treatment includes restoring sinus rhythm, which is the best result of AF treatment. Only by restoring normal sinus rhythm can we achieve the goal of complete treatment of AF. Therefore, for any patient with AF, a treatment to restore sinus rhythm should be attempted. Control of fast ventricular rate For patients with AF who cannot restore sinus rhythm, drugs can be used to slow down the faster ventricular rate. To prevent thrombosis and stroke if the sinus rhythm cannot be restored during atrial fibrillation, prevent thrombosis and stroke.

Medical treatment is still an important method for treating AF today. Drug treatment includes anticoagulation to prevent thromboembolic complications, control of ventricular rate, pharmacological cardioversion and maintenance of sinus rhythm. Non-pharmacological treatment includes direct current cardioversion, catheter ablation, buried Atrial Defibrillator and Permanent Pacemaker Treatment.