RESUMO
Heart transplantation is one of the most effective strategies to treat end-stage heart failure. Multiple challenges, such as difficulty in preservation of heart allograft, rejection and postoperative complications, emerge in heart allotransplantation. After decades of research and practice, most problems have been resolved. Nevertheless, the shortage of donor organs has become increasingly prominent. To alleviate the shortage of donor organs, artificial heart and heart xenotransplantation have captivated attention, and obtained significant progress in recent years. The application of artificial heart in clinical practice has significantly enhanced the survival rate of patients with end-stage heart failure, which is expected to become the standard treatment for end-stage heart failure. Heart xenotransplantation still faces many challenges, which is still far from clinical application. In this article, the history of heart transplantation, development of heart allotransplantation, use of artificial heart and research progress on heart xenotransplantation were reviewed, and the future development direction of heart transplantation was predicted.
RESUMO
Heart transplantation is the primary therapeutic option for patients with end-stage heart failure. The shortage of donors has been the main limiting factor for the increasing quantity of heart transplantation. With persistent updating and introduction of novel technologies, the donor pool has been increasingly expanded, such as using the heart from older donors, donors infected with hepatitis C virus, donors dying from drug overdose or donation after cardiac death (DCD) donors, etc. Meantime, the proportion of recipients with advanced age, multiple organ dysfunction, mechanical circulatory support and human leukocyte antigen antibody sensitization has been significantly increased in recent years. The shortage of donors, complication of recipients' conditions, individualized management of immunosuppressive therapy and prevention and treatment of long-term cardiac allograft vasculopathy are all challenges in the field of heart transplantation. In this article, novel progresses on donor pool expansion, improving the quality of recipients, strengthening the diagnosis and treatment of rejection, and preventing cardiac allograft vasculopathy were reviewed, aiming to prolong the survival and enhance the quality of life of patients with end-stage heart failure on the waiting list or underwent heart transplantation.
RESUMO
Objective To report the primary experience of open placement of triple-branched stent graft for acute Stanford type A aortic dissection. Methods Between June 2008 and September 2009, 20 well-selected patients with acute Stanford type A aortic dissection underwent open placement of triple-branched stent graft for total arch reconstruction. When core cooling to a 20℃ nasophageal temperature, perfusion to the lower body was discontinued and the ascending aorta was transected at the base of the innominate artery. Through a transverse incision, the triple-branched stent graft was inserted into the true lumen of the arch and descending aorta, and each side arm of the stent graft was positioned one by one into the arch branches.The transected stump of the ascending aorta was reconstructed by inner proximal stent-free dacron tube of the main graft and outer teflon felt, and subsequently continuous anastomosis to the 1-branched dacron tube graft was made. Results Open placement of triple-branched stent graft was technically successful in all patients. The mean cardiopulmonary bypass time, aortic cross-clamp time and lower body arrest time were (163.2 ±19.2) min, (89.4 ±10.0) min and (32. 7 ±6. 6)min, respectively. Transient postoperative neurological dysfunction was observed in 1 patient and acute renal failure in 1 patient. All patients were discharged from the hospital. Their computed tomographic scans at 3 months postoperatively showed that all stent grafts were fully opened without distortion. In the vascular stent implantation site the dissected false lumen was eliminated. The false lumen of the descending aorta distal to the stent graft was closed with thrombus in 16 cases. Conclusion Open placement of triple-branched stent graft is a new effective technique for total arch reconstruction in acute type A aortic dissection. Patients have the indications of the extensive primary repair of the thoracic aorta without primary intimal tears in the arch may be the best candidates for this new technique. The size of the stent graft, the distances between two neighboring side arm grafts and the prevention of the intimal trauma during the placement are crucial for successful open placement of triple-branched stent graft.