Surgical Treatment of LA/RA Myxoma (Left Atrium / Right Atrium Myxoma)

Surgical removal of a left atrial (LA) or right atrial (RA) myxoma is the definitive treatment, as it is generally curative and prevents potentially life-threatening complications like embolization, valve obstruction, and heart failure. The surgery is typically straightforward but requires precise planning and expertise due to the delicate nature of the heart and the location of the tumor.

Preoperative Considerations

Before surgery, several steps are taken to ensure the safety of the procedure:

1. Anticoagulation Therapy:
• Patients with mobile tumors or a history of embolic events are often given anticoagulants (such as heparin) to reduce the risk of thromboembolism (blood clots traveling from the tumor).
2. Preoperative Imaging:
• Echocardiography (TTE and TEE) helps determine the size, location, and mobility of the tumor.
• CT/MRI may provide further details, especially in complex cases or when planning the surgical approach.
3. Cardiopulmonary Bypass (CPB):
• Since the surgery involves the heart, cardiopulmonary bypass (CPB) is typically required to temporarily take over the function of the heart and lungs, allowing the surgeon to work on a still heart.
4. General Anesthesia:
• The patient is placed under general anesthesia for the surgery to ensure they are unconscious and pain-free.

Surgical Procedure for LA/RA Myxoma

1. Accessing the Heart

• Midline Sternotomy:
• A midline sternotomy (cutting through the breastbone) is the most common approach. This allows the surgeon to access both the left and right atria.
• In rare cases where the tumor is localized or if the patient has contraindications to a sternotomy, a mini-thoracotomy (smaller incision) or anterior thoracotomy may be used.
• Cardiopulmonary Bypass:
• Once the sternum is opened, the patient is connected to cardiopulmonary bypass. This machine takes over the functions of the heart and lungs, ensuring that oxygenated blood continues to circulate through the body while the heart is temporarily stopped.
• Aortic cannulation is typically used to access the circulatory system.

2. Tumor Removal

• Incision into the Atrium:
• The surgeon makes an incision in the atrial wall, most commonly in the left atrium (for LA myxomas) or right atrium (for RA myxomas).
• The tumor is often located near the interatrial septum, typically near the fossa ovalis, so this area is carefully opened to allow access to the tumor.
• Tumor Excision:
• The tumor is carefully excised (cut out) from its attachment point, which is often in the interatrial septum.
• If the tumor is pedunculated (attached by a stalk), it is removed by cutting through the stalk.
• The surgeon must ensure that the tumor is completely removed to avoid recurrence.
• Examination of Surrounding Structures:
• The surgeon will also inspect surrounding structures, particularly the mitral valve (in the case of LA myxomas) or tricuspid valve (for RA myxomas), as the tumor can affect valve function.
• If any damage is found, repairs may be made to prevent regurgitation (leakage of blood through the valve).

3. Closing the Heart

• After the tumor is removed, the heart is carefully closed:
• Atrial sutures are used to close the incision in the atrial wall.
• In some cases, if there is significant damage to the heart valves or other structures, the surgeon may repair or replace the affected valve(s).
• Reversing Cardiopulmonary Bypass:
• Once the heart is closed, the surgeon will reverse the effects of cardiopulmonary bypass. The heart is gradually restarted, and the patient’s blood flow is returned to normal.
• Inotropic support (drugs to help the heart pump effectively) may be used if necessary.

4. Postoperative Monitoring

• Chest Tube Placement:
• A chest tube may be inserted to drain any excess fluid or air that may accumulate around the heart after surgery.
• ICU Monitoring:
• The patient is closely monitored in the intensive care unit (ICU) for 1-2 days post-surgery. Monitoring includes vital signs, cardiac function, and oxygenation status.
• Arrhythmias are common after surgery, especially if the tumor was near the atrial septum or if a valve repair was performed. These may require medical management.

Postoperative Care

1. Pain Management:
• Postoperative pain is managed with analgesics, often via an intravenous (IV) route or through epidural analgesia, especially if sternotomy was performed.
2. Ventilator Support:
• The patient may need mechanical ventilation for a short period after surgery, especially if they had compromised respiratory function preoperatively.
3. Anticoagulation:
• Anticoagulation therapy may continue postoperatively to prevent thromboembolism, especially if there was any preoperative embolic history or significant turbulence of blood flow during surgery.
4. Physical Rehabilitation:
• Patients may undergo cardiac rehabilitation to help regain strength and function after surgery, particularly if they had symptoms like heart failure before surgery.
5. Follow-Up Imaging:
• Echocardiograms are typically performed to assess the success of the surgery and ensure that the tumor has been completely removed and there are no new issues (such as valve leaks).

Risks and Complications

Like any surgery, myxoma excision carries potential risks:

• Infection: Although rare, infections can occur at the incision site or inside the heart.
• Bleeding: The heart's delicate structures, especially the atrial septum, are at risk of bleeding during surgery.
• Arrhythmias: Patients are at risk of developing atrial fibrillation or other arrhythmias postoperatively, especially if the tumor was large or involved the atrial septum.
• Cardiac Complications: Rarely, issues like valve regurgitation, cardiac tamponade (fluid buildup around the heart), or damage to other heart structures can arise.
• Embolization: If embolization (tumor or blood clot traveling from the heart to other organs) occurred before surgery, there may be damage to other organs (like the brain or kidneys) that needs to be addressed.

Outcomes and Prognosis

• Excellent Prognosis: Most patients experience a full recovery and a return to normal function, particularly if the tumor was benign and the surgery was uncomplicated.
• Recurrence: The recurrence of a myxoma after complete excision is rare but possible, especially if tumor fragments were left behind. This is why complete resection is critical.
• Malignant Myxomas: Although most myxomas are benign, if the tumor is malignant, additional treatments like chemotherapy or radiation may be needed.

For patients with left atrial myxoma, the prognosis is excellent after complete surgical removal, and most patients have long-term survival with no recurrence. For right atrial myxoma, the prognosis is also favorable if the tumor is successfully excised.

Conclusion

Surgical excision of LA or RA myxomas is the standard treatment, offering an excellent prognosis for patients, particularly those with benign tumors. The procedure typically involves cardiopulmonary bypass, tumor removal, and, if necessary, valve repair. Careful postoperative monitoring and follow-up imaging are essential to ensure the success of the surgery and prevent complications.