An interesting case report Pericardial diverticulum coincidently prevent cardiac tamponade in type A aortic dissection: An interesting case report 報告人：陳彥成 指導人：黃建偉

Introduction Pericardial cysts and diverticula: 1/100,000 Pericardial diverticula: connection with pericardium. Pericardial cysts: Isolated pericardial masses. Mostly asymptomatic, and are accidently found by image studies.

Case report A 67-year-old woman complained about severe chest pain and dyspnea while jogging. Hypertension and chronic hepatitis B. Denied any trauma history. Vital signs: No hypotension. Consciousness: Clear. The laboratory data: Normal.

Enhanced Chest CT Type A aortic dissection was diagnosed (Arrow head). One homogeneous, well-circumscribed pericardial mass 6.9 x 6.9 x 7.2cm (Arrow).

Emergency Operation(1) The surface of the pericardial cavity was smooth, grayish and elastic. About 450ml discharge was removed. On the right side mediastinum, an orifice about 3.5 x 4 cm was noticed. The pericardial cavity was full of bloody discharge

Emergency Operation(2) Pathology report : Pericardium with fibrosis and infiltration of chronic inflammatory cells. Ascending aorta replacement and pericardial diverticulum resection. The defect was repaired with Prolene 4-0.

Discussion(1) Pericardial diverticula were first described by Dublin in 1837. Acquired: Inflammatory pericarditispericardial effusions Increased pressure herniation diverticulum. Congenital: Ventral parietal recess of the pericardial celom. With proximal part or “neck” constriction, the diverticula become isolated or pedicled pericardial cysts. Haas 14 observed that common sites of origin are along the lines of pericardial reflection, on the right side at the base of the aorta or between the superior and inferior venae cava, and on the left side in the region of the pulmonary veins. He proposedthat pericardial herniation may occur in these potentially weak areas, where the fibrous pericardium merges with the adventitia of the great vessels, and the parietal serous layer is reflected as the epicardium.

Discussion(2) Pericardial diverticula are usually asymptomatic. Physical examinations and auscultation are normal presentation. Image studies can offer clues for diagnosis. X-Ray. Computed tomography.

Discussion(3) There is no consensus of management of pericardial diverticula. Mary ET al. made a review with 36 cases and found about 66% pericardial diverticula have symptoms. Surgical resection with thoracoscopy for diagnosis and treatment.

In Our Case Asymptomatic pericardial diverticulum played a critical role in type A aortic dissection by chance. 100 to 200ml pericardial effusion is enough to cause cardiac tamponade. This pericardial diverticulum provided about 200 to 250ml cavity.

Conclusion Pericardial diverticula can be congenital defects secondary to inflammatory pericarditis. Surgical resection with thoracoscopy is recommended for treatment and diagnosis In specific condition, the pericardial diverticulum can relieve pericardial effusion and prevent cardiac tamponade.

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