Benign tumors: Mucinous tumors Primary tumors of the heart are rare, and more than half of them are mucinous tumors. Although mucinous tumors can occur in any of the heart chambers, most mucinous tumors grow in the atrial septum and are most commonly found in the left atrium. In only about 15% of patients, the tumor is located in the right atrium. The patient’s symptoms often suggest a diagnosis, such as mitral valve obstruction or systemic embolism, and a definitive diagnosis can be made by performing cardiac ultrasound. Transverse myxoma Transverse myxoma originates from cardiac muscle cells and is most commonly seen in infants and children. Rhabdomyosarcomas tend to multiply and grow in the septum, causing inflow and outflow tract obstruction in the left and right ventricles of the heart. Heart failure is the most common symptom and is caused by obstruction of the heart chambers and valves. If the patient is less than 1 year old and does not have tuberous sclerosis, surgical treatment can be performed, as it is still possible to enucleate the tumor at this time. Unfortunately, however, in patients with symptomatic tuberous sclerosis, the tumors are so extensive and multiple that surgery is not able to help. Fibromas Fibromas arise from fibrous tissue cells, are often solitary, and are the second most common benign cardiac tumor. Fibromas occur most often in children. The typical fibroma is a single white tumor that can grow in the left or right ventricle and is often calcified. Clinical symptoms result from the obstruction of blood flow through the affected area of the heart. Fibromas that calcify can be seen by x-ray. Cardiac ultrasound can clarify the presence and location of the tumor. If the tumor is limited and can be removed, surgical resection may be performed. If the mass cannot be removed completely, a partial resection may be performed to relieve symptoms. In children with extensive fibroid growth, heart transplantation may be considered. Papillary elastofibromas Papillary elastofibromas are small, single tumors that resemble bulky growths. They often grow on the atrial surface of the mitral and tricuspid valves and may involve tendon tissue. Papillary elastofibromas can also grow on the ventricular surface of the aortic and pulmonary valves. These tumors are usually asymptomatic but can cause flow obstruction and embolism. Papillary elastofibromas can be found accidentally during surgery or on cardiac ultrasound when something resembling a bulky growth is found on the valve. Because the tumor can lead to serious consequences, papillary fibroids should be surgically removed once diagnosed. Papillary fibroids should be removed conservatively to allow for valve repair without valve replacement. Lipomas are usually single, localized tumors that can grow anywhere in the heart or on the pericardium. Lipomas are usually asymptomatic. Larger lipomas with significant symptoms should be surgically removed. If a small lipoma is discovered accidentally during cardiac surgery, it can be removed without increasing the risk of surgery. Malignant tumors: Whether the tumor is primary or metastatic, the indication for surgery depends on the size and location of the tumor and the absence of metastases outside the heart. If completely resected, surgery provides better symptomatic relief than radiotherapy and or chemotherapy alone. Complex malignant tumors of the left side of the heart are difficult to fully expose during surgery, and in this case the use of autologous heart transplantation techniques allows the surgeon to completely remove the tumor. Autologous heart transplantation involves cutting out the patient’s own heart and removing the tumor outside the body. The defect created by the resected tumor is then repaired and the heart is reimplanted. Metastatic tumors of the heart are more common than primary malignancies and are rarely solitary and often result in pericardial effusion. Surgical treatment of these patients is limited to subxiphoid pericardial drainage or pericardial windowing to relieve recurrent pericardial effusions. Invasion of the right atrium by subdiaphragmatic tumors Tumors of the abdomen and pelvis can invade the inferior vena cava and grow upward to the right atrium, most commonly renal cell carcinoma. Surgery is performed through an abdominal incision to ensure that the renal tumor can be removed. The tumor can usually be removed through the abdominal cavity, from the inferior vena cava under the diaphragm. If the tumor cannot be removed from the abdominal cavity, a median sternotomy is performed, extracorporeal circulation is established and systemic hypothermia is applied, followed by the initiation of deep hypothermic arrest of the circulation. During the short period of cardiac arrest, the cardiac surgeon incises the right atrium and assists the nephrologist in pushing the tumor into the abdominal portion of the inferior vena cava and removing the tumor. Extracorporeal circulation is then resumed, the patient is rewarmed, and the patient is routinely evacuated from extracorporeal circulation.