Low-profile porcine bioprosthesis (Liotta): pathologic findings and mode of failure in the long-term.

Background And Aims Of The Study: The Liotta low profile porcine bioprosthesis (LBP) was designed in order to minimize complications due to excessive protrusion of the stent prongs in the left ventricle.

Materials And Methods: From April 1984 to November 1993, 25 LBP surgical explants were available for pathology study, which included gross and X-ray evaluations. Reoperation was performed after a mean period of 95 +/- 25 months (range 46 to 143 months), in five males and 20 females (mean age at implantation 51.

The role of right side objects in left side neglect: a dissociation between perceptual and directional motor neglect.

Based on a test introduced by Tegnér and Levander, Brain 114, 1943-1951, 1991, right brain-damaged patients were assigned to a group with unilateral perceptual neglect and a group with directional motor neglect. Brain scans showed that all directional motor neglect patients had frontal lesions, whereas in perceptual neglect patients the frontal lobes were always spared. All patients were asked to execute two tasks, which were also administered to a control group.

Fatal obstruction of the left ventricular outflow tract caused by low-profile bioprostheses in the mitral valve position.

Two cases of fatal left ventricular outflow tract obstruction following mitral valve replacement with low-profile bioprostheses are described. This unfortunate experience shows that correct orientation of the prosthesis is mandatory also when using low-profile bioprosthetic valves to avoid this complication, particularly in patients with a small left ventricular cavity.

The Meadox-Gabbay pericardial xenograft: failure of the unicusp principle.

Durability of a new bioprosthesis, the Meadox-Gabbay unileaflet pericardial xenograft, was evaluated by reviewing a series of 12 patients who received this device in the mitral position from 1983 to 1985. Bioprosthetic failure necessitated reoperation in 5 patients 21, 22, 53, 66, and 81 months after placement. Three patients died of cardiac failure after 31, 52, and 70 months; no postmortem examinations were done.