ABSTRACT
Tissue engineered scaffolds have emerged as a promising solution for heart valve replacement because of their potential for regeneration. However, traditional heart valve tissue engineering has relied on resource-intensive, cell-based manufacturing, which increases cost and hinders clinical translation. To overcome these limitations, in situ tissue engineering approaches aim to develop scaffold materials and manufacturing processes that elicit endogenous tissue remodeling and repair. Yet despite recent advances in synthetic materials manufacturing, there remains a lack of cell-free, automated approaches for rapidly producing biomimetic heart valve scaffolds. Here, we designed a jet spinning process for the rapid and automated fabrication of fibrous heart valve scaffolds. The composition, multiscale architecture, and mechanical properties of the scaffolds were tailored to mimic that of the native leaflet fibrosa and assembled into three dimensional, semilunar valve structures. We demonstrated controlled modulation of these scaffold parameters and show initial biocompatibility and functionality in vitro. Valves were minimally-invasively deployed via transapical access to the pulmonary valve position in an ovine model and shown to be functional for 15 h.
Subject(s)
Biocompatible Materials , Biomimetics/methods , Heart Valves/surgery , Tissue Scaffolds , Animals , Heart Valve Prosthesis , Nanofibers , Sheep , Tissue Engineering/methodsABSTRACT
OBJECTIVE: Atrial fibrillation puts patients at significant risk for embolic stroke originating from the left atrial appendage. Few means are available for safe, effective, and durable left atrial appendage occlusion. A new clip device was evaluated with regard to safety and effectiveness for epicardial left atrial appendage occlusion. METHODS: Patients with atrial fibrillation undergoing elective cardiac surgery through a median sternotomy were enrolled for concomitant epicardial clip placement. Early postoperative and 3-month follow-up computed tomography studies were used to assess clip stability and left atrial appendage perfusion. RESULTS: From September 2007 to December 2008, 34 patients underwent successful clip placement. No device-related complications occurred. Operative mortality was 8.8% and not study or device related. Deployment was rapid, and left atrial appendage occlusion was confirmed by intraoperative transesophageal echocardiography in all patients. In addition to excellent clinical outcomes (no stroke/transient ischemic attack), serial computed tomography demonstrated stable clip location and appendage perfusion at 3 months in all patients. CONCLUSION: Safe, effective, and durable left atrial appendage occlusion can easily be achieved with this new clip. Further trials are necessary to evaluate the role of the left atrial appendage occlusion in stroke prevention.
Subject(s)
Atrial Appendage/surgery , Atrial Fibrillation/surgery , Cardiac Surgical Procedures/instrumentation , Embolism/prevention & control , Stroke/prevention & control , Surgical Instruments , Aged , Aged, 80 and over , Atrial Appendage/diagnostic imaging , Atrial Fibrillation/complications , Atrial Fibrillation/diagnosis , Atrial Fibrillation/mortality , Cardiac Surgical Procedures/adverse effects , Cardiac Surgical Procedures/mortality , Echocardiography, Transesophageal , Embolism/etiology , Equipment Design , Female , Humans , Male , Middle Aged , Pilot Projects , Risk Assessment , Risk Factors , Sternotomy , Stroke/etiology , Time Factors , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
Nesiritide, a recombinant B-type natriuretic peptide used for the intravenous treatment of acute decompensated congestive heart failure. Concerns have been raised about the long-term use of nesiritide, but data is scarce regarding its use in acute congestive heart failure and during cardiac surgery. We conducted a retrospective data review to address the safety of nesiritide for pretreatment of patients undergoing mitral valve surgery.
