The production of viable biological heart valves is of central interest in tissue engineering (TE). The aim of this study was to generate decellularized heart valves with an intact ultra-structure and to repopulate these with endothelial cells (EC) under simulated physiological conditions. Decellularization of ovine pulmonary valve conduits was performed under agitation in detergents followed by six wash cycles. Viability of EC cultures exposed to washing solution served to prove efficiency of washing. Resulting scaffolds were free of cells with preserved extracellular matrix. Biomechanical standard tension tests demonstrated comparable parameters to native tissue. Luminal surfaces of decellularized valvular grafts were seeded with ovine jugular vein EC in dynamic bioreactors. After rolling culture for 48 h, pulsatile medium circulation with a flow of 0.1 L/min was started. The flow was incremented 0.3 L/min/day up to 2.0 L/min (cycle rate: 60 beats/min), while pH, pO2, pCO2, lactate and glucose were maintained at constant physiological levels. After 7 days, a monolayer of cells covered the inner valve surface, which expressed vWF, indicating an endothelial origin. A complete endothelialization of detergent decellularized scaffold can be achieved under simulated physiological circulation conditions using a dynamic bioreactor system, which allows continuous control of the culture environment.

Background: To address glenoid bone deficiency, 2 competing surgical approaches are currently recommended: transplantation of a structural bone graft or the coracoid transfer according to Latarjet. Nonetheless, no clear advantages for either procedure are evident. Hypothesis: The Latarjet procedure will provide an equivalent beneficial effect on glenohumeral stability as the placement of an intra-articular bone graft. Study Design: Controlled laboratory study. Methods: Stability testing of 8 cadaveric shoulders was performed in a dynamic shoulder simulator under 4 different conditions: (1) anteroinferior capsulotomy, (2) anteroinferior glenoid defect, (3) transplantation of a contoured bone graft, and (4) Latarjet procedure. Translational movement of the humeral head in response to a load of 25 N was evaluated in the anterior and anteroinferior directions. Results: The Latarjet procedure significantly reduced translation by 354% relative to the glenoid defect condition at 30° of abduction and by 374% at 60° of abduction. In comparison, the bone graft significantly reduced translation by 179% at 30° of abduction and by 159% at 60° of abduction. The effect of the bone graft was lowest in external rotation at 60° of abduction where a decrease of translation of 133% was observed. Comparing both reconstruction techniques, the Latarjet procedure resulted in significantly less anterior and anteroinferior translation at 60° of abduction. Conclusion: Biomechanically, the Latarjet procedure outperforms the bone graft in reducing translation in anteroinferior glenoid bone defects. The advantage of the Latarjet procedure is particularly evident at 60° of glenohumeral abduction. Clinical Relevance: On the basis of the results of this biomechanical study, the authors recommend the Latarjet procedure for restoring stability in shoulders with a significant glenoid bone defect.