Aortic valve (AV) stenosis is the most treated heart valve disease and the only curative treatment is the surgical AV replacement or the transcatheter prosthesis implantation. Bovine and porcine pericardium is used for fabricating biological heart valve prostheses but the durability is limited to 10-15 years. We use optical coherence tomography (OCT), a volumetric imaging technique with microscopic resolution, to monitor fiber structure and calcification of pericardium samples. Validated by histology, OCT at 880 and 1300 nm central wavelength captures the relevant structural features and shows a high potential for material testing of pericardium towards improved AV prostheses.