FIBROUS TISSUE OVERGROWTH AND PROSTHETIC VALVE ENDOCARDITIS - REPORT OF A CASE

Mechanical valve stenosis without restricted occluder motion and parav aluvular leakage developed in a patient who had undergone patch closur e of partial atrioventricular septal defect and replacement of the lef t atrioventricular valve 13 years previously. Dense calcification of t he supravalvular region was shown in a cineradiogram, whereas transtho racic and transesophageal echocardiography failed to reveal any obstru ctive mechanism. Elevated transprosthetic pressure gradient with unres tricted occluder motion suggested prosthetic valve stenosis resulting from fibrous tissue overgrowth, although this was not visualized by th e modern diagnostic imaging tools. Reoperation confirmed calcified fib rous tissue overgrowth obstructing the mechanical valve inflow. Examin ation of resected tissue revealed prosthetic valve endocarditis due to ct-streptococcus, Paravalvular leakage accompanying fibrous tissue ov ergrowth may indicate the presence of prosthetic valve infection even if the clinical manifestations are scarce.