Increasing survival of organ transplant patients by reducing time interval for transported organs

Apr 27 2007

Preservation of an organ intended for transplant during transport from donor to recipient is of primary concern in ensuring a successful transplant.

Research presented at the ISHLT 27th Annual Meeting and Scientific Sessions today explores two diverging systems for pump preservation - the Organ Care System (OCS) and the cold preservation method, and how they each effect survival for heart transplant patients.

The cold preservation method, which has been in practice for more than 25 years, delivers the organ in a non-functioning state immersed in a cold solution for preservation during transport. The time during transport in this method is referred to as cold ischemic time (CIT), more specifically the interval beginning when an organ is removed from the donor and is cooled with the solution, to the time when the organ is implanted.

Conversely, the Organ Care System (OCS) is based on warm blood perfusion technology, which it uses to maintain organs in a warm, functioning state. This state mimics the environment of the human body during transport from organ donor to recipient. Nutrient rich, oxygenated blood is continuously pumped through the heart in order to maintain the organ in a living, beating, state. Preserving an organ with this method reduces CIT and allows for evaluation of organ function during transport.

New data presented during a late afternoon session on Wednesday, Concurrent Session 2 Cardiac Ischemic Time: Warm, Cold, or Pump, highlighted the benefits of reducing or eliminating CIT, such as increased availability of donor organs, improved transplant outcomes, and reduced costs associated with end stage organ failure. Presentations during the session outlined research results demonstrating that reducing CIT will increase survivorship, and further how the OCS may eliminate CIT almost entirely.

Gero Tenderich, M.D., Clinic for Thoracic and Cardiovascular Medicine, Bad Oeynhausen, Germany, provided results from the PROTECT I clinical trial, Prospective Multi-Center European Trial To Evaluate the Safety and Performance of the Organ Care System for Heart Transplants, during the Wednesday session (Abstract 10). The PROTECT I trial, which was performed in Europe, studied the efficacy of the OCS in regards to survivorship. The results demonstrate the use of the OCS in maintaining and transporting donated hearts for transplant surgery. Results showed 100 percent survival of patients 30 days post surgery. Results also revealed that using the OCS allowed for patients to spend less time on the ventilator and experience a quicker recovery in the hospital. The ability of the OCS to assess organ function was also discussed. The trial sites participating in the PROTECT I study included the Clinic for Thoracic and Cardiovascular Medicine, Bad Oeynhausen and the German Heart Institute in Berlin, Germany, as well as Papworth Hospital and Harefield Hospitals, NHS Trusts in Cambridge and Middlesex, United Kingdom, respectively.

The U.S. Food and Drug Administration has recently granted IDE approval to initiate the pilot phase of the PROCEED multi-center clinical trial in the U.S. to evaluate the safety and performance of the OCS for heart transplants. The PROCEED trials will take place at five centers, including University of Pittsburgh Medical Center in Pittsburgh; Heart, Lung, and Esophageal Surgery Institute in Pittsburgh; UCLA Medical Center in Los Angeles; The Cleveland Clinic Heart and Vascular Institute in Cleveland, The University of Chicago Hospitals Cardiac Center in Chicago and Brigham & Women's Hospital in Boston.

"The PROTECT trial results establish validity of the Organ Care System. Given its relatively recent introduction to the transplant world, we are excited about the results and look forward to seeing what further tests will demonstrate about this innovative system," said Bruce Rosengard, M.D., Director of Cardiac Transplantation at Massachusetts General Hospital and former ISHLT board member.

Analysis of data from studies conducted in the United Kingdom and Australia were presented by Julian Gooi, M.D., Alfred Hospital, Melbourne, Australia, The Potential Impact of Reducing Cold Ischaemic Time on Cardiac Transplant Survival (Abstract 8) during the same Concurrent Session. The analysis concluded that a CIT of less than one hour would result in longer-term survival or an increase in life-years gained (LYG). Overall, the research showed that there were 2.2 LYG per donor heart for the United Kingdom transplant program, and 2.1 LYG per donor heart for the Australian transplant program. Dr. Gooi's presentation demonstrated how reworking the means of transport and developing central procurement and transplant centers could be beneficial to the transplant community.

"These results should alert the transplant community of issues that need immediate attention in order to increase survivorship in transplant patients. The amount of life years gained through better efficiency within the organ transport system is astonishing," continued Dr. Rosengard.

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