Heterotopic transplantation of a decellularized and recellularized whole porcine heart.

OBJECTIVES: One of the final treatments for end-stage heart failure is heart transplantation. However, a shortage of donor hearts has created a long waiting list and limited benefits. Our ultimate goal is to create a whole beating heart fabricated on an organ scaffold for human heart transplantation. Here, we successfully performed the first transplantation using a decellularized whole porcine heart with mesenchymal stem cells. METHODS: A porcine heart was harvested following cardiac arrest induced by a high-potassium solution and stored at -80°C for 24 h. The porcine heart was completely decellularized with 1% sodium dodecyl sulphate and 1% Triton X-100 under the control of perfusion pressure (100 mmHg) and maintained at 37°C. A decellularized whole-heart scaffold was sterilized with gamma irradiation. Cultured mesenchymal stem cells were collected and either infused into the ascending aorta or injected directly into the left ventricular wall. Finally, recellularized whole-heart scaffolds were transplanted into pigs under systemic anticoagulation treatment with heparin. Coronary artery angiography of the transplanted heart graft was performed. RESULTS: In our decellularization method, all cellular components were removed, preserving the heart extracellular matrix. Heterotopic transplantations were successfully performed using a decellularized heart and a recellularized heart. The scaffolds were well perfused, without bleeding from the surface or anastomosis site. Coronary angiography revealed a patent coronary artery in both scaffolds. The transplanted decellularized heart was harvested on Day 3. Haematoxylin and eosin staining showed thrombosis in the coronary arteries and migrated inflammatory cells. Haematoxylin and eosin staining of the transplanted recellularized heart showed similar findings, with the exception of injected mesenchymal stem cells. CONCLUSIONS: To the best of our knowledge, this is the first report of heterotopic transplantation of a decellularized whole porcine heart with mesenchymal stem cells. The scaffolds endured surgical procedures. We detected short-term coronary artery perfusion in the transplanted scaffolds by angiography. Future studies should analyse the histological features of transplanted decellularized scaffolds and optimize the system for recellularization to apply this unique technology clinically.

Alternative peripheral perfusion strategies for safe cardiopulmonary bypass in atrial septal defect closure via a right minithoracotomy approach.

OBJECTIVES: In cases of cardiac surgery via a minimally invasive right minithoracotomy approach, cardiopulmonary bypass is established with peripheral arterial cannulation, frequently with a single femoral artery. Occasionally, alternative perfusion access is required to prevent perfusion site-related complications. In this study, the feasibility of alternative perfusion strategies was verified by comparing the postoperative outcomes and complications. METHODS: The records of 91 consecutive patients (68 women, 23 men; mean age 40.7 ± 16.5 years) who underwent atrial septal defect (ASD) closure via a right minithoracotomy approach between January 2009 and September 2014 were reviewed. Patients were divided into two groups: those with single femoral arterial access (SF group, n = 84), and those with alternative perfusion access (ALT group, n = 7, bilateral femoral arterial cannulation in 6, side-arm graft anastomosed to the femoral artery in 1). RESULTS: Femoral artery diameter was smaller in the ALT group than in the SF group (6.5 ± 0.5 vs. 7.3 ± 1.0 mm, P = 0.013). Operating time was longer in the ALT group than in the SF group (259.2 ± 54.0 vs. 208.3 ± 54.9 min, P = 0.031). One patient was converted to ascending aortic cannulation owing to high perfusion pressure. Postoperative major cardiac or cerebrovascular events, such as death, stroke, or myocardial infarction, did not occur in either group. CONCLUSIONS: Alternative perfusion access was safe in ASD closure via a right minithoracotomy approach. Precise preoperative evaluation of the iliofemoral artery is important for choosing the appropriate perfusion strategy.

Hybrid Thoracic Endovascular Aortic Repair for Intercostal Patch Aneurysm after Thoracoabdominal Aortic Replacement.

We report a case of hybrid thoracic endovascular aortic repair for intercostal patch aneurysm after thoracoabdominal aortic replacement. Eighteen years ago, a 63-year-old woman with Marfan syndrome had undergone thoracoabdominal aortic replacement with reimplantation of the intercostal artery in an island fashion. Follow-up computed tomography (CT) revealed a remaining intercostal patch aneurysm of diameter 60 mm 17 years after the last operation. Hybrid thoracic endovascular aortic repair for exclusion of this intercostal patch aneurysm was successfully performed, with visceral artery bypasses. Postoperative CT showed no anastomotic stenosis or endoleak.