(P260) RIGHT ATRIAL AND CAVAL RECONSTRUCTION FOR CARDIAC SARCOMA

Case background: Primary cardiac tumours are exceedingly rare, with an incidence rate between 0.0001% - 0.001% based on previous literature, the majority of which are benign neoplasms. Amongst primary cardiac malignancies, mesenchymal sarcomas represent the most common diagnosis. The prognosis of patients with cardiac sarcomas is quite poor, with average survival being approximately 6 months and only 10% of patients surviving past 24 months with medical therapy alone. Despite this, there have been reports of prolonged survival with early, aggressive surgical reconstruction in combination with adjuvant chemotherapy and/or radiation therapy. However, complete resection can often be difficult to achieve due to the often advanced tumour invasion at the time of presentation, and the technical challenge presented by the need for extensive reconstruction of cardiac structures. We present the case of a primary cardiac sarcoma and describe our surgical approach to right atrial and bi-caval reconstruction.

Management Challenges:

Case Report: A 27year-old man presented with chest pain and dyspnea. Initial workup included a chest x-ray that showed a significantly enlarged cardiac silhouette. Non contrast Chest CT suggested pericardial effusion which led to a pericardiocentesis (bloody fluid, negative for malignancy) with resolution of symptoms Four weeks later, his symptoms recurred. This time, after drainage (again bloody), he had a contrast CT, which demonstrated a large lobulated mass of the mediastinum and right atrium (RA) suspicious for a sarcoma. Echocardiography confirmed the above findings. We arranged for a percutaneous biopsy, which confirmed synovial sarcoma and after a full course of chemotherapy, repeat imaging showed a resectable tumour. We thus proceeded with resection.

The patient was taken to the operating room and a standard median sternotomy performed. We found a large tumour involving the pericardium adjacent to the right atrium. It extended to the SVC and IVC and onto the anterior RV. There was a significant amount of edema which helped resection of the mass in some locations. Using superior vena cava and femoral venous cannuation along with ascending aortic cannulation, we were able to perform the resection. The tricuspid valve appeared to be spared and was structurally normal and competent. After resection of the right atrium, pericardium, SVC and IVC, a Dacron graft was sewn to the residual SVC and IVC, and a window was made into the graft. A bovine pericardial patch was used to reattach the heart to the graft. Intraoperative transesophageal echocardiogram demonstrated no new valvular lesions or ventricular dysfunction. Samples of the tumour resection margins were sent for histopathological examination. Given that we resected the sinoatrial node, an epicardial dual chamber pacer was placed. The patient was transferred to the CVICU in stable condition and was discharged without complication. .

Discussion: The surgical resection of cardiac sarcomas pose several technical challenges related to the extent of resection required as well as the anatomic structures requiring reconstruction. We present a case of a right atrial sarcoma as an avenue to demonstrate our surgical approach to aggressive resection and reconstruction of right-sided cardiac structures. Our strategy involves a multidisciplinary approach to diagnosis and treatment, with the use of neoadjuvant chemotherapy and post therapy assessment with subsequent operation if deemed appropriate. Current knowledge seems to suggest that this approach provides the highest likelihood for extended survival. Nevertheless, there remains a dearth of evidence to guide the perioperative management of patients with primary cardiac malignancies. To this end, we have conceived and spearheaded the INTERACT project (International Registry to Assess Cardiac Tumours), which is designed to help consolidate international experiences with cardiac tumours in order to help standardize the diagnostic and therapeutic strategies employed in their care.