Limitations of multimodality imaging in the diagnosis of pannus formation in prosthetic aortic valve and review of the literature

Figure 1 Transesophageal echo and fluoroscopy. A: Transesophageal Echo: 3-chamber view at 129°, with zoom in the LV outflow tract, showing the prosthetic valve with its parallel discs; B: Fluoroscopy showing the almost parallel tilting discs. Both exams confirm an adequate prosthetic valve opening. LA: Left atrium; LV: Left ventricle; Ao: Aorta.

Figure 2 Explanted prosthetic valve. A concentric pannus formation is seen, obstructing the effective prosthetic orifice. A: Ventricular side; B: Arterial side.

Figure 3 Histology of the pannus. Structure of collagen fibers, interspersed with small vessels and capillaries, surrounded by giant cells. A: Hematoxylin and Eosin staining; B: Masson’s Trichrome staining.