What is the “maze procedure”?
Doctor’s word: The cardiac surgery procedure for atrial fibrillation, called the “maze procedure,” was invented and modified by the American academic Cox in the 1980s. To date, more than 80,000 people worldwide have undergone this treatment. The procedure restores a normal heartbeat rhythm by sequentially slicing the atria along a maze of pathways so that electrical signals can only be transmitted along the maze. (i.e., the classic maze procedure) Patients with both coronary artery disease and atrial fibrillation, like Mama Zhang, are ideally suited for atrial fibrillation ablation treatment in conjunction with cardiac surgery. The goal is to strive to restore sinus rhythm, enable the heart to achieve normal rhythm contraction and pumping function, reduce complications, improve quality of life, and prolong life.
Atrial fibrillation (abbreviated as AF) is one of the most common clinical arrhythmia diseases. Patients with atrial fibrillation lose the normal rhythm of heartbeat, the heart muscle cannot contract synchronously and effectively, the pumping function decreases, and a large amount of blood accumulates in the myocardial trabeculae of the inner wall of the atria and easily clots. If the blood clot is dislodged and flows throughout the body with the blood flow, it will easily block the peripheral blood vessels. According to statistics, the incidence of cerebral infarction in patients with atrial fibrillation is 20%.
The methods of atrial fibrillation treatment are
1, drug treatment
Oral medication, which cannot cure atrial fibrillation independently, is often combined with medication after the patient receives direct current resuscitation or after hospitalization, and must be precisely monitored to prevent side effects.
2. Direct current resuscitation
Two electrode pads are placed in appropriate locations on the patient’s chest to restore the heart rhythm by distributing current through the defibrillator. Patients need to be hospitalized, and DC resuscitation alone cannot cure chronic atrial fibrillation, and its efficacy decreases significantly as the patient’s history of atrial fibrillation increases, atrial dilatation increases, and age increases.
3. Permanent pacemaker installation
A permanent pacemaker is surgically implanted, which generates electrophysiological signals to stimulate the heart to beat rhythmically. Permanent pacemakers are expensive, and their implantation in the patient’s body causes significant and irreversible damage to the heart, resulting in a high risk of stroke.
4. Implantable defibrillators
Surgical implantation of a defibrillator to eliminate atrial fibrillation is not only expensive, but also ineffective in patients with chronic atrial fibrillation.
5. Cardiology catheter ablation
A special catheter is inserted through a vein into the heart to the location where the abnormal electrical signals occur, and these electrophysiological signals are blocked by heat, thereby eliminating atrial fibrillation. Endocardial catheter ablation requires pre-detection of the location where the abnormal electrophysiological signals occur, long operation time (2-4 hours), limited operation area (only pulmonary vein isolation, no guarantee of wall penetration), difficulty in treating the whole heart, and therefore low success rate (the success rate of endocardial catheter ablation in patients with valvular atrial fibrillation is only about 10%); the operation is relatively expensive (more than 90,000).
6.Cardiac surgery ablation procedure
Under the condition that the heart can be seen directly, all electrophysiological signal conduction is blocked along a specific pathway, and the only normal electrophysiological conduction of the heart is preserved, so that the heart completely restores rhythmical beat and the muscle regains effective contraction. Cardiac surgical ablation has a high cure rate (over 70% success rate) and is currently the only effective cure for chronic atrial fibrillation. The price is 10-20 thousand.
Patients who are also suffering from valvular disease, or coronary heart disease, or congenital heart disease that requires cardiac surgery, have significant side effects from medication for atrial fibrillation, still suffer from thrombosis or stroke after anticoagulation, or cannot be cured by cardiology therapy.
Patients with chronic atrial fibrillation – Cardiac surgery for atrial fibrillation ablation is the only effective way to cure atrial fibrillation
According to evidence-based statistics, atrial fibrillation is 96% effective immediately after surgery, 90% of patients are in sinus rhythm at discharge, and 80% of patients maintain good outcomes at 6-month follow-up, significantly higher than with catheter interventional ablation.
Meet the “Maze Procedure”
The incidence of atrial fibrillation is high in cardiac surgery patients (20% in coronary artery disease, 10% in congenital heart disease, and up to 80% in rheumatic heart disease). For these patients, undergoing the maze procedure at the same time as the cardiac surgery can be a double whammy.
The classical maze is the traditional cutting and suturing of the atrial muscles along the maze route. With the development of new surgical energy sources such as radiofrequency, microwave, cryo, ultrasound and laser, the traditional cut and suture is replaced by physical energy damage to the atrial muscle (i.e. ablation), making the procedure easier, faster and safer than the standard maze procedure. Among them, the most common application is radiofrequency treatment, i.e., the ablation pen is used to draw lines according to the labyrinth diagram to denature the tissue to form a “labyrinth wall”, and the whole treatment process takes only 15 minutes, and the treatment effect is close to the classical labyrinth surgery.
It is worth mentioning that in recent years, with the development of minimally invasive cardiac surgery technology, thoracoscopic non-stop atrial fibrillation ablation technology has further expanded the scope of surgical treatment of atrial fibrillation, which is also applicable to patients with simple atrial fibrillation due to the small trauma and good effect without opening the chest. After the procedure, the surgeon administers specific doses of antiarrhythmic and anticoagulant drugs (most commonly used drugs such as cortisone and warfarin) according to the patient’s condition. After discharge from the hospital, the patient needs regular follow-up ECG, cardiac ultrasound and thyroid function, oral dose of up to six months, oral anticoagulation with warfarin if persistent atrial fibrillation >48 hours occurs, and evaluation of the therapeutic effect 6 months after the operation, and return to sinus rhythm in cured patients.