Pericardial pseudocyst along atrioventricular groove

Abstract

Cystic lesions in relation to the pericardium are a rare congenital lesion with an estimated incidence of 1 per 100,,000. Pericardial cysts may be classified as congenital or acquired. Here, we present a case of a pericardial pseudocyst having a horseshoe configuration along the atrioventricular groove in a middle-aged subject with no previous relevant medical history. The patient underwent open surgery for the same with histopathological diagnosis being established. This paper highlights the differentials for a cystic pericardial lesion in imaging in addition to the histopathological entity of a pericardial pseudocyst.

Figure 1.

1(a) Echocardiogram (in IU 22, Philips) done in apical 4 CH chamber view shows a heterogeneous hyperechoic lesion (*) in the right and left AV groove region causing significant compression on the LV & RV chambers. 1 (b) Post contrast CT [in Brilliance ICT 256 slice, Philips Healthcare, Cleveland, OH] axial section showing hypodense cystic lesion (*) along the right and left AV groove with peripheral wall enhancement. A focus of calcification (yellow arrow) is noted in the thick wall towards the left side. In addition, bilateral pleural effusion secondary to heart failure is also seen. 1 (c–f) Cardiac MRI [in Avanto Fit 1.5T,Siemens, Erlangen, Germany)], SA images (c, d, f) and 4 CH image (e) showing the predominantly hyperintense thick walled cystic lesion (*) with horseshoe configuration (d–f) along the AV groove posteroinferior to the heart. T1 SA slice (d) showed hyperintense content indicative of haemorrhagic content. Post-contrast delayed PSIR image (e, f) showing the peripherally enhancing thick wall of the cyst. Otherwise, no significant pericardial effusion was detected in the present imaging. AV, atrioventricular; 4 CH, four chamber; LA, left atrium; LV, left ventricle; PSIR, phase sensitive inversion recovery; RA, right atrium; RV, right ventricle; SA, short axis.

Figure 2.

DW (a, c)and ADC (b) images of heart in axial section showing areas of diffusion restriction at b-value = 400 s mm⁻², in right AV groove region (yellow arrows in a, b) and areas of non-restriction in other locations (Dotted arrows in a–c). GRE image (Figure 2 d) in short axis section showing areas of blooming with in the walls of the cyst (yellow arrowheads). ADC, apparent diffusion coefficient; DW, diffusion-weighted; GRE, gradient refocussed echo images.

Figure 3.

Intraoperative photograph showing the cyst cavity (*) after emptying of the contents with the thickened wall.

Figure 4.

Thick fibrocollagenous cyst wall (a) and adherent fibrinous and haemorrhagic content (_*) with foreign body type of multinucleate giant cells (B-arrow) and macrophages (b). The cyst wall lacks any lining epithelium (c) and shows hemosiderin pigment (d, e) and focal lymphocytic infiltration (f). [Stain: a–c, f: Haematoxylin and eosin; d, e: Perls Prussian blue; Magnification = Scale bar (a = 200 µm; d = 100 µm; b, c, e, f = 20 µm)]

Figure 5.

Algorithm for cardiac MRI diagnosis in pericardial cystic lesions. CMR, cardiac MR.