Hybrid Atrial Fibrillation Ablation

Up to 5% of the general population is affected by atrial fibrillation (AF), a difficult condition that can lead to life-threatening complications such as embolic stroke and tachycardia-induced cardiomyopathy. Anticoagulation and antiarrhythmic drugs (AADs) are used in the initial care. Some individuals may be candidates for catheter-based ablation; however, they are vulnerable to recurrent AF. Patients undergoing concurrent heart surgery typically have open surgical ablative treatments done. There is growing support for using novel energy sources to undertake Cox-maze III lesion set variations in the context of lone AF. Researchers have developed a Cox-maze III-like lesion set without the requirement for a sternotomy or cardiopulmonary bypass using a hybrid thoracoscopic-epicardial and catheter-based endocardial method. This method also makes it easier to exclude the left atrial appendage, which offers some protection against embolic events in the case that atrial arrhythmias recur.

What is Hybrid Atrial Fibrillation Ablation?

A frequent kind of cardiac arrhythmia (abnormal heart rhythm) known as atrial fibrillation (AF, or A-fib) is characterized by irregular, and typically quicker, heartbeats. Although AF may not pose a life-threatening concern, it should be treated to avoid heart damage. Medication and cardioversion (electrical shocks) are utilized in certain instances to stop the arrhythmia. The irregularity typically goes away on its own. If this approach fails to successfully control your arrhythmia, you may be a candidate for ablation. Ablation introduces a catheter through the groin into the heart and forms a scar tissue barrier to block the aberrant electrical signals. Even though multiple procedures are occasionally required, one ablation is frequently sufficient. The next step is a hybrid ablation if the arrhythmia has been persistent for some time or if it continues even after several ablations.

Hybrid Atrial Fibrillation Ablation Benefits

The following are the advantages of hybrid AF ablation:

Increased likelihood of effectiveness in lowering your A-fib symptoms
A minimally invasive procedure using less than one-inch incisions
For most patients, hospitalization and recovery times are short.

Hybrid Atrial Fibrillation Ablation Indications

The vast majority of patients with paroxysmal AF and a structurally healthy heart will experience effective AF suppression with catheter ablation employing radiofrequency radiation (focused heat) that only targets the pulmonary veins (pulmonary vein isolation, or PVI). A cardiac electrophysiologist performs this procedure, which often only necessitates an overnight hospital stay. When this is successful, the patient's quality of life improves since the symptoms are under control and anti-arrhythmic medication is not required. When physicians assume that AF is triggered and maintained by dysfunctional areas outside of the pulmonary veins, hybrid ablation is considered. The majority of patients who are candidates for hybrid ablation have persistent AF (AF that lasts continuously for more than 7 days) or have had unsuccessful PVI attempts in the past. Patients who will most likely benefit from the hybrid technique are identified by the doctor. Because their AF sources are distinct from or far from the pulmonary veins, these patients typically represent the difficult end of the spectrum of AF. Hybrid ablation is not appropriate for all AF patients.

Before Hybrid Atrial Fibrillation Ablation

To determine whether a patient is a good candidate for this surgery, the specialist and the cardiac surgeon will schedule separate meetings with the patient. Several tests are performed as part of the procedure's work-up, including but not limited to blood tests, chest X-rays, and cardiac CT scans.

After your outpatient evaluation with a heart surgeon, you will be provided information about the admissions process. In a clinic before admission, a nurse will examine you. A few blood tests will be done in advance of the procedure. You will typically spend the night in the hospital before your surgery. The cardiac anesthetist will be available for consultation with the patient before the procedure. For this procedure, specific directions and preparations may include temporarily stopping medications, fasting, and using a special soap.

Anticoagulation medication must be stopped 48 to 72 hours before the operation. Before the procedure, you must discuss this with the surgeon. Due to an increased risk of bleeding, failure to cease taking these medications could cause the treatment to be canceled.

Hybrid Atrial Fibrillation Ablation Evaluation

Patients with chronic or long-lasting AF, a history of at least one unsuccessful catheter ablation, anatomical constraints to catheter ablation (including interrupted inferior vena cava), and those who have tried and failed at least one antiarrhythmic drug are eligible. Patients with a clear history of AF don't need any additional electrophysiological tests beyond those carried out during previous catheter ablations. To assess ejection fraction, rule out valvular or other potential contributory structural heart disease, and estimate left atrial size, transthoracic echocardiography is used. To exclude coronary artery disease, cardiac catheterization or preoperative coronary CT are frequently used. Patients having a history of sternotomy, a left atrial thrombus, or severe structural heart disease are not considered candidates for this treatment. It is not advised for patients with severe cardiomyopathy, an ejection fraction (EF) of less than 25%, or a very big left atrium ([LA]; greater than 6.5 cm) to undergo this operation due to the minimal possibility of benefit.

Hybrid Atrial Fibrillation Ablation Procedure

The right and left video-assisted thoracoscopy (VATS) and catheter-based ablation are the three main stages of the hybrid AF treatment.

Preparation and positioning

A double-lumen endotracheal tube, a large bore intravenous access, and an arterial line are used to put the patient to sleep. There is no need for a pulmonary artery catheter, which would also stop the superior vena cava encircling lesion from developing. To rule out the presence of a left atrial appendage thrombus or other structural cardiac problems, transesophageal echocardiography (TOE) is done. If urgently necessary, femoral arterial and venous access sheaths are implanted to provide cardiopulmonary bypass. To enable selective elevation of the right and left hemithoraces, the patient is positioned supine with the arms tucked and inflatable positioning devices positioned under each scapula. If necessary, sterile external defibrillator pads are positioned outside of the operating field to aid in cardioversion.

Right Video-Assisted Thoracoscopic Component

With the appropriate VATS component, we start. A 12-mm trocar is inserted in the anterior axillary line's fourth intercostal gap after the right lung is deflated. To insert the thoracoscope, carbon dioxide insufflation at 5-8 mmHg is employed. One 12-mm mid-axillary line port is positioned at the third or fourth interspace, and a 5-mm mid-clavicular line trocar is positioned at the second or third interspace. The LigaSure device, an electrothermal bipolar tissue sealing system, is used to open the pericardium 3 cm anterior to the phrenic nerve, superiorly to the pericardial reflection, and inferiorly past the oblique sinus. To improve vision, pericardial stay sutures are applied to the lateral pericardium and brought through different stab wounds. The oblique and transverse sinuses are abruptly opened. The LA dome is then abruptly separated from the soft tissue surrounding it. The Lumitip lighted dissector is carefully inserted behind the right pulmonary veins (RPVs) from inferior to superior, pushing the tissue between the pulmonary veins and the right pulmonary artery against the lighted dissector until the tip of the instrument is superior to the right superior pulmonary vein and the LA. This procedure is repeated until the right pulmonary veins (RPVs) are sufficiently dissected. After the dissector is removed and the pulmonary veins are checked for blockage, vessel tape is wrapped over them to maintain control. The AtriCure Synergy bipolar clamp is then passed from inferior to superior and gently closed around the LA, as medial onto the LA and as far away from the pulmonary veins as feasible, once the RPVs have been isolated. Around the RPVs, radiofrequency (RF) energy leaves an ablative scar. There are four to six ablations that follow one another. The AtriCure Multifunctional Pen is then used to test the RPVs, pacing, and sensing to guarantee full bidirectional block across the ablation line after the clamp has been released. The pen is also used to test the ganglionic plexi (GPs) in the area; when these areas are stimulated, a bradycardic reaction is a sign that the GPs are active and are ablated as a result. The left atrial roof and floor lines interconnecting the RPV and LPV isolation lines close to the superior pulmonary veins are finished using the Coolrail ablation device. The multipurpose pen creates a lesion from the left PVI line to the left atrial appendage's (LAA) tip. The left atrial appendage is addressed after a successful ablation. The AtriClip sizing instrument is used to thoracoscopically measure the LAA. The appendage is gently pulled between the clip arms of an AtriClip device of proper size. Before formal deployment, the clip is closed and TOE is utilized to confirm that the appendage has been completely excluded. The clip can be modified if the incomplete exclusion is seen on TOE. After that, the pen is swapped out for a Coolrail linear ablation device (Atricure), which is used to start an ablation line from the right superior pulmonary vein along the dome of the LA, to be finished from the left VATS technique as well as the floor of the left atrium from the right inferior pulmonary vein across towards the left veins. The multipurpose pen is used to draw a line along the right atrium from the superior vena cava (SVC) to the inferior vena cava (IVC). By carefully positioning the clamp well above the site of the sinoatrial node, the bipolar clamp is used to produce a lesion enclosing the SVC. To improve visualization during the catheter ablation phase of the hybrid operation, the junction spots between the superior and inferior LA lines and the PVI line are indicated with a 5-mm Clip. One interrupted suture is used to seal the pericardium. One of the port incisions is used to install a 24-Fr channeled drain, and the remaining incisions are then sewn together. The procedure's right VATS component is now finished.

Left Video-Assisted Thoracoscopic Component

Three ports that mirror the right chest's incisions are used to access the left chest, although they are moved posteriorly to account for the location of the left ventricle. The Ligament of Marshall is separated using the LigaSure device after the pericardium has been cut posterior to the phrenic nerve. The left pulmonary veins (LPVs) are separated from the nearby soft tissue, just like the right side, and then surrounded with the illuminated dissector and vessel tape. The LPVs' confluence is surrounded by a bipolar clamp, which is used to perform ablation and confirm the bidirectional block. GPs are examined and, if active, ablated. The clip is set in place and removed once the ideal position has been determined. With the incisions closed as on the right side, the left VATS component is finished. A channeled drain is left in the left pleural space.

Catheter-Based Ablation

After the surgical ablation, the team performs catheter-based ablation, usually during the same hospitalization but occasionally with separate admission. It also allows for the completion of the remaining lesion set, which consists of the coronary sinus line and the cavotricuspid isthmus line, and the confirmation of the surgical ablation lesions. The electrophysiology lab receives patients, who are given conscious sedation. Catheters are inserted into several locations, such as the right ventricle, coronary sinus, His bundle, and right atrium, after obtaining femoral access. A catheter with an irrigated tip is used to perform ablations when intracardiac echocardiography is used. Each patient goes through three steps. First, the SVC isolation line is verified. The next step is the creation and bidirectional block test of a cavotricuspid isthmus line. With intracardiac echocardiography being used to verify extension to the left atrial side, coronary sinus ablation is then carried out. Isoproterenol infusion is administered after these first three steps to induce any atrial arrhythmias. Transseptal approaches are used if there is AF or flutter. Heparin is administered to a goal-activated clotting time of 350 s for patients who require the trans-septal approach; this procedural anticoagulant is well tolerated because the catheter ablation follows the thoracoscopic operation by several days. Following mapping and ablation of the induced flutters, the roof line block and pulmonary vein (PV) isolation are tested. It is administered again to make sure there aren't any further flutters. Treatment for induced AF involves PV isolation testing, mitral isthmus line imaging, and complex fractionated atrial electrograms. Isoproterenol retests were not performed on patients with provoked AF. The operation is finished after the establishment of the cavotricuspid isthmus line and coronary sinus ablation in patients who do not experience atrial flutter or fibrillation brought on by isoproterenol. Following catheter-based ablation, the patient's therapeutic anticoagulation is restarted, and after receiving close outpatient follow-up for the management of their antiarrhythmic and anticoagulant drugs, they are discharged.

After Hybrid Atrial Fibrillation Ablation

Following the procedure, the patient will spend the next 24 hours in the intensive care unit before being transferred to the heart surgery department for a further 2-3 days. The heart will be closely watched during this period. Blood pressure, oxygen saturation, heart rate, and cardiac rhythm will all be regularly inspected. 24-48 hours after surgery, a tube that was used to drain fluid from around the heart will be taken out. Fluids will be given through an IV, and painkillers will be provided to help with the discomfort. Your pain will be evaluated by the ward nurse on a scale of 1 to 10, and the proper amount of painkillers will be given. If you need more pain medication and are in pain, kindly ask. Your nursing staff will assist you with sitting in a chair and moving around the hospital the day after the procedure. This will aid in your surgical recovery. The following day, the cardiac surgeon will review the operation with you and answer any concerns you may have. Your doctor will actively manage your arrhythmia medications and will give you a visit in the hospital following the procedure. Your heartbeat may be regular at this point, but if you are still in AF, don't get discouraged.

Your discharge time and date will be informed to you one day in advance. A dressing will be applied to your chest, which you or your doctor can remove after two weeks. You will leave the hospital with 2 stitches on the left side of your chest, which your doctor will remove in 5 days. A list of drugs will be given to you, along with referrals for echocardiography to be done in two weeks and a cardiac CT to be done in four. After the procedure, you will already have a scheduled appointment to see your doctor in his office. After four weeks, the cardiac surgeon will reevaluate you.

On wounds, avoid using any creams or ointments. Visit your GP pretty quickly and let the cardiac surgeon know if you have any unusual discomfort or redness. Take a shower. You can go through shower safety precautions with the nurse before being discharged.

Wait patiently until the wounds are fully healed, at least two to three weeks, before going swimming or using the bathtub. Keep moving at home. Between activities, rest. It is typical to get fatigued easily, but your stamina should gradually increase. For 3 weeks after the treatment, avoid lifting anything more than 5 kg. For two weeks, don't use a motor vehicle.

Hybrid Atrial Fibrillation Ablation Outcomes

The specific patient circumstances have a significant impact on the hybrid ablation success rate. Doctors are aware that maintaining a healthy weight through diet and exercise, treating sleep apnea if it is present, actively managing any cardiovascular disease, and tightly controlling blood pressure and blood sugar all considerably increase the success rate of any AF intervention for patients. As a general rule, doctors expect each patient who is being considered for this treatment to have a minimum success rate of 70%. Some people would be refused because they exhibit clinical characteristics that point to poor outcomes. Importantly, scar tissue has prevented the surgical part of hybrid ablation from being performed again. If necessary, patients can undergo further catheter ablation after hybrid ablation.

Hybrid Atrial Fibrillation Ablation Risks

Fortunately, considering the nature of the surgery, they are rare. These issues are the most important ones:

Cardiac perforation or damage. This risk is real with any procedure involving the heart. Although it is a very uncommon consequence, it must be treated with a sternotomy (breastbone cut) and injury repair. Since cardiac surgeon performs the first step of the treatment, they are well-suited to effectively handle such a problem should it arise.
Pericarditis. A membrane that surrounds the heart, the pericardium. The surgeon will incise the sac to access the heart, and the tools and catheter used in the procedure may rub against the sac. This part of the surgery, along with others, causes pericarditis, an inflammation of the sac (inflammation of the pericardium). These issues may present as discomfort, fever, or an accumulation of fluid in the pericardial sac.
Stroke. Although extremely rare, it is nonetheless important to highlight. The development of tiny clots in the atrium may happen either during or after the treatment. To check for any and confirm that there are none before the procedure, you will have intraoperative transesophageal echocardiography. You will start taking blood thinners soon after surgery to prevent cardiac clots from forming.
Pericardial effusion is the accumulation of fluid surrounding the heart. The pericardium's inflammation may be the secondary cause of this. Doctors may observe it or use a needle to aspirate it, depending on its size. This might happen after you've been discharged. Breathlessness, fever, flu-like symptoms, sweating, and a rapid heartbeat can all be brought on by it. If you suffer any of these symptoms, please get in touch with your doctor.
Incisional hernia. A hernia under the incision may develop in some patients. This could cause abdominal tissues like the intestines to intermittently move under the skin incision (hernia). If you see such a development, contact your cardiac surgeon.

Conclusion

With complication rates equivalent to the early catheter-based ablation technique, the hybrid ablation procedure for AF yields positive results. Given the unsatisfactory outcomes of the catheter-based technique in those with a more persistent form of arrhythmia, early results point to a possible role for this innovative strategy in a subset of patients with AF. To identify the ideal hybrid ablation approach and longer-term outcome results, more research is required.