atrial fibrillation, referred to as atrial fibrillation, is a very common arrhythmia. According to statistics, the incidence of atrial fibrillation in people over 6 years old is 1%, and it increases with age.
One cause
The onset of atrial fibrillation is paroxysmal or persistent. Paroxysmal atrial fibrillation can be seen in normal people and occurs during emotional excitement, after surgery, exercise or acute alcoholism. Atrial fibrillation can also occur in patients with heart and lung diseases when acute hypoxia, hypercapnia, metabolic disorder or hemodynamic disorder occur. Persistent atrial fibrillation occurs in patients with original cardiovascular diseases, and is common in rheumatic valvular disease, coronary heart disease, hypertensive heart disease, hyperthyroidism, constrictive pericarditis, cardiomyopathy, infective endocarditis, heart failure and chronic pulmonary heart disease. Atrial fibrillation occurs in people who have no known basis of heart disease, which is called solitary atrial fibrillation.
ii clinical manifestations
the severity of atrial fibrillation symptoms is affected by the speed of ventricular rate. When the ventricular rate exceeds 15 beats per minute, patients may have angina pectoris and congestive heart failure. When the ventricular rate is slow, the patient is not even aware of its existence. Atrial contraction disappears during atrial fibrillation, and cardiac output decreases by 25% or more. < P > Atrial fibrillation has a high risk of systemic embolism. Embolus comes from the left atrium or ear, which is caused by blood stasis and atrial loss of contractility. Patients without valvular heart disease are complicated with atrial fibrillation, and the chance of stroke is 5 ~ 7 times higher than those without atrial fibrillation. The incidence of cerebral embolism is higher when mitral stenosis or mitral prolapse complicated with atrial fibrillation.
three treatments
1. Etiological treatment: We should try our best to find the primary diseases and inducing factors and make etiological treatment.
2. Acute attack: If the patient has a rapid ventricular rate and has symptoms and signs of acute cardiovascular insufficiency, synchronous electric cardioversion should be the first choice. For those with good cardiovascular function, the initial treatment goal is to slow down the ventricular rate. Digitalis, beta blockers or verapamil are used to keep the ventricular rate at 6-8 beats per minute at rest, and after light exercise, the heart rate will increase by no more than 1 beats per minute. Digitalis can be used alone or in combination with beta blockers or calcium antagonists as needed. Beta blockers and verapamil should not be used in patients with heart failure and hypotension, and digitalis and verapamil should not be used in patients with preexcitation syndrome complicated with atrial fibrillation.
3. Paroxysmal atrial fibrillation: Paroxysmal atrial fibrillation is called when the duration of atrial fibrillation is shorter than 12 months, and the chances of successful cardioversion are greater, and the chances of maintaining sinus rhythm after cardioversion are greater. Quinidine is the most commonly used and effective drug in class ⅠA, but it may lead to fatal ventricular arrhythmia. Procaine amine is also very effective. Before cardioversion with Class IA drugs, β blockers should be given to slow down the conduction of atrioventricular node, so as to prevent the above drugs from antagonizing vagus nerve. Otherwise, when atrial fibrillation turns into atrial flutter, the concealed conduction of atrioventricular node will be weakened, leading to the acceleration of ventricular rate. The efficacy of flucanine and propafenone of class ⅠC drugs in converting atrial fibrillation is similar to that of class ⅠA, but it can also lead to ventricular arrhythmia. Amiodarone can also effectively convert atrial fibrillation. When drug cardioversion is ineffective, synchronous electrical cardioversion can be tried. In order to prevent left-handed thrombosis, warfarin should be given for 3 weeks before cardioversion (to extend the thromboplastin time to 1.3 ~ 1.5 times of the control value) and continue for 2 ~ 4 weeks after cardioversion.
Before deciding on cardioversion therapy for patients with chronic atrial fibrillation, we should fully consider whether atrial fibrillation can be maintained for a long time after being converted to sinus rhythm. The duration of atrial fibrillation (the longer the course, the more difficult it is to maintain after cardioversion), the degree of atrial dilation (the larger the atrium, the lower the success rate) and the age of the patient (the lower the success rate of the elderly patients) are all important factors affecting the maintenance of sinus rhythm after cardioversion.
In order to prevent the recurrence of atrial fibrillation, quinidine, propafenone or amiodarone can be used.
At present, radiofrequency ablation has been successfully used to treat paroxysmal atrial fibrillation.
4. persistent atrial fibrillation: those with atrial fibrillation lasting more than 12 months are called persistent atrial fibrillation. Generally, cardioversion is no longer used, but medication is used.
For rapid atrial fibrillation, digoxin is a commonly used oral drug. The overdose of digoxin is toxic to the heart. Patients and family members must learn to listen to the ventricular rate with a stethoscope (be careful not to count the pulse), and adjust the dosage according to the heart rate. If the heart rate is fast, the dosage will be increased, while if the heart rate is slow, the dosage will be reduced, so as to maintain the heart rate at 7-9 beats/minute. Digoxin should be used for a long time. Those who have been poisoned by digoxin can continue to use it as long as the condition requires after the poisoning is completely recovered.
Patients with chronic persistent atrial fibrillation have a high incidence of embolism, especially those with a history of embolism, thrombus in the left atrium diagnosed by ultrasound, severe mitral stenosis and artificial heart valve replacement are all high-risk patients. People under the age of 6 who have no history of heart disease are low-risk patients. For high-risk patients, it is generally advocated that long-term anticoagulants (long-acting aspirin 325mg per day or warfarin) should be given, while low-risk patients do not need long-term application. It should be pointed out that there is no consensus on the long-term anticoagulation treatment of atrial fibrillation. Even patients who need long-term anticoagulation therapy should pay attention to the individual's different situations, weigh the pros and cons, and fully consider that drugs may increase the risk of potential bleeding.
For patients with frequent attacks, rapid ventricular rate and ineffective drug therapy, atrioventricular node ablation of his bundle can be performed, and a frequency-adaptive ventricular pacemaker can be implanted at the same time.
About the doctor's statement that atrial fibrillation is now under control and arrhythmia is a normal phenomenon, is the doctor's statement correct?
The more you used to be a cardiologist, the above statement is basically correct. Because there is a process of drug defibrillation, namely: atrial fibrillation-paroxysmal, short-burst atrial fibrillation-atrial premature beat-sinus arrhythmia-sinus rhythm. In this process, it is only the last step that the heartbeat and pulse are regular, and the middle three gears are irregular!