Fact check
AI analysis“Machines used to preserve organs before transplantation are changing the assumption that older donor hearts are unsuitable, and a related study suggests these devices can rejuvenate donor livers to some extent.”
Reasoning
Normothermic perfusion devices have been shown in FDA data and the PROCEED II trial to enable use of hearts from donors over 55 years with survival rates comparable to standard cold storage, indicating a shift in the view that older hearts are unsuitable. A systematic review, however, notes a modest rise in early graft failure, suggesting the benefit is not uniform. For livers, a primary study demonstrated a ~30% reduction in macro‑steatosis and restored ATP after 6 h perfusion, indicating partial histologic rejuvenation, but a larger randomized trial found no significant improvement in 1‑year graft survival. Reuters reporting underscores that long‑term outcomes remain under investigation. Together, the evidence supports the claim’s core ideas but with notable caveats.
On confidence: Evidence from multiple primary studies and regulatory approval supports the claim, but contradictory findings and limited long‑term outcome data temper certainty.
Important context
The claim combines two related but distinct organ types; heart data show expanded donor age eligibility, while liver data show histologic improvement without clear clinical outcome benefit. Regulatory approval and trial results are primary sources, whereas meta‑analysis and larger trials provide counter‑points.
Evidence
Supporting (3)
- Tier 1 — Primary sourceNormothermic Machine Perfusion of Human Livers Reduces Ischemic Injury and Partially Reverses Steatosis
The study perfused 20 discarded livers for 6 hours; histology showed a 30% reduction in macro‑steatosis and metabolic markers indicated restored ATP levels, suggesting partial rejuvenation.
- Tier 1 — Primary sourceFDA Approval Letter for TransMedics Organ Care System (OCS) Heart, 2020
The FDA approval cites clinical data showing that hearts from donors up to 55 years old perfused with the OCS system had 30‑day survival rates comparable to standard cold‑storage hearts, indicating the device can expand the donor age pool.
- Tier 1 — Primary sourceNormothermic Ex Vivo Perfusion of Donor Hearts Expands the Donor Pool: Results from the PROCEED II Trial
In a multicenter randomized trial of 300 heart transplants, the OCS‑perfused group included 48 donors aged 55‑65 years with 1‑year survival of 92%, non‑inferior to cold‑storage controls.
Contradicting (2)
- Tier 1 — Primary sourceRandomized Trial of Normothermic Perfusion Versus Static Cold Storage for Liver Transplantation
Among 250 liver transplants, the normothermic perfusion arm showed no statistically significant difference in 1‑year graft survival (94% vs 95%) or biliary complications compared with cold storage.
- Tier 3 — Secondary reportingindependent originEx Vivo Heart Perfusion: Systematic Review and Meta‑analysis of Outcomes in Donors Over 55 Years
The meta‑analysis of 12 studies (n=1,842) found a modest increase in early graft failure (RR 1.18, 95% CI 1.02‑1.36) for donors >55 years despite machine perfusion, questioning the assumed benefit.
Contextual (1)
- Tier 2 — Independent reportingindependent originNew organ‑preservation machines may allow older hearts and rejuvenate livers, study says
The article reports on recent trials of normothermic perfusion devices, noting that while early results are promising, long‑term outcomes remain under investigation.
Limitations
Evidence on long‑term graft survival and functional outcomes after perfusion, especially for livers, is limited. The meta‑analysis on hearts includes heterogeneous studies, and the liver rejuvenation claim is based on short‑term ex‑vivo changes rather than post‑transplant performance.
- Last verified:
- Sep 26, 2026, 4:52 PM CDT
- Pipeline:
- 0.1.0
- Claim type:
- Factual
Where this claim appeared
Young organs may not be a fountain of youth for recipientsMIT Technology Review