Excision of Giant Right Atrial Myxoma on Beating Heart

Introduction

Cardiac myxomas are usually solitary and develop in the atria, with 75% originating in the left atrium and 15-20% originating in the right atrium. They characteristically arise from or near the interatrial septum at the border of the fossa ovalis membrane (1). Myxomas present with either embolic or valve obstruction/regurgitation symptoms. Surgical excision is the treatment of choice. Right atrial myxomas can be excised safely on a beating heart with the aid of cardiopulmonary bypass.

Patient selection

• Aortic regurgitation should be excluded before attempting to use the beating heart technique.
• Atrial septal defects should also be excluded.
• Tumors invading or arising from the interatrial septum are not suitable for the beating heart technique.

Operative steps

• Full sternotomy is the best approach for this technique.
• After full heparinization, the cannulation of aorta, SVC, and IVC are carried out.
• Selective high cannulation of SVC is preferred using a right angle cannula.
• Gentle manipulation of the atrium should be considered during cannulation to avoid embolization.
• Tapes with snugger are passed around the SVC and IVC.
• Going on bypass.
• After reaching full flow, both tapes are snared to secure SVC and IVC.
• MAP should be maintained throughout the procedure. Vasoconstrictors may be needed.
• The right atrium is opened to expose the myxoma.
• Careful resection of the myxoma without causing ASD.
• After excision of the myxoma and closure of right atrium, the last couple of stitches are left loose to de-aireat the right atrium after releasing the IVC tape.
• Weaning of bypass as usual.

Tips and pitfalls

• Cardioplegia purse string suture should be in place and ready to use when needed.
• Close attention should be given to monitor ECG for any changes or bradycardia. If ECG changes start to happen, the aorta should be clamped and the heart should be stopped using cardioplegia.
• Temperature should not drift below 35 degrees.
• Left ventricle should be regularly inspected for distension.
• If the septum is opened, the crossclamp should be applied and the cardioplegia should be used to stop the heart to prevent air from entering the left heart and avoid air embolization. 

Reference

1. Bruce CJ. Chapter 45: Cardiac tumors. In: Otto CM, eds. The Practice of Clinical Echocardiography. 3rd ed. Philadelphia, PA: WB Saunders/Elsevier; 2007:1108-1137.