SESSION TYPE: Miscellaneous Student/Resident Case Report Posters
PRESENTED ON: Tuesday, October 23, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: Thymoma, a neoplasm of thymic epithelial cells, accounts for 50% of mediastinal masses1. The presentation of thymomas can be variable depending on their location and proximity to peripheral structures. Extrinsic left atrial compression by a thymoma is an uncommon source of hemodynamic compromise rarely reported in the literature3. We present a patient experiencing presyncope with an X-ray suggestive of a left ventricular aneurysm.
CASE PRESENTATION: A 59-year-old patient with a history of vertigo presents with dizziness and vomiting. He denies chest pain, dyspnea, blurred vision, or sensorimotor deficits. On examination, nystagmus and Dix-Hallpike maneuvers were negative. X-ray suggests a large ventricular aneurysm (Figure 1). Electrocardiogram, brain MRI and carotid duplex were negative. Chest CT reveals a well-circumscribed, extra-cardiac mass compressing the left atrium (Figure 2). Ejection fraction was normal. Biopsy confirmed the mass to be a B2 Type thymoma. A diagnosis of presyncope, secondary to vertigo was made, with an incidental finding of a thymoma. The patient’s thymoma was resected resulting in complete resolution of symptoms.
DISCUSSION: Thymomas are commonly incidental findings and nearly one-half are asymptomatic1. Chest X-ray offers limited information. Accurate diagnosis requires CT scans and echocardiography. Among those presenting with symptoms, the primary determinant is location of the thymoma to peripheral structures. The presyncopal symptoms, initially thought to be secondary to vertigo, and the CT diagnosed thymoma were perceived to be two separate entities. However, the following lines of thought would suggest otherwise. Firstly, the left atrial compression by the thymoma would result in obstruction of left atrial inflow. Secondly, the left ventricular function would not be impaired. In this case, the echocardiography revealed a normal ejection fraction. With compromised inflow, the total ventricular preload decreases and leads to functional tamponade2,3. With significant hemodynamic compromise, cerebral blood flow is reduced precipitating a presyncopal episode. Complete resolution of symptoms following thymus resection also supports this conclusion.
CONCLUSIONS: Although thymomas are primarily asymptomatic, cardiac compression is a possible manifestation that cannot be ignored. Fortunately, accurate diagnoses can be made with chest CT and echocardiography. Furthermore, surgical resection can lead to complete resolution of symptoms.
1) Oldham, HN et al. Primary Tumors and Cysts of the Mediastinum. Archives of Surgery. 1968.
2) Raza, S.T et al. Hemodynamically Significant Extrinsic Left Atrial Compression by Gastric Structures in the Mediastinum. Annals of Internal Medicine. 1995.
3) D’Cruz, IA et al. Echocardiographic manifestations of mediastinal masses compressing or encroaching on the heart. Echocardiography. 1994.
DISCLOSURE: The following authors have nothing to disclose: Kathir Balakumaran, Pulin Shah, Gregory Thibodeau, Sanjay Singh
No Product/Research Disclosure InformationSaba University School of Medicine, Saba, Netherlands Antilles