31P MRS of heart grafts provides metabolic markers of early dysfunction

• Published in: European journal of cardio-thoracic surgery 2005-10, Vol.28 (4), p.576-580
• Main Authors: Caus, Thierry, Kober, Frank, Mouly-Bandini, Annick, Riberi, Alberto, Métras, Dominique R, Cozzone, Patrick J, Bernard, Monique
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphate - analysis; Bioengineering; Biological and medical sciences; Biomarkers - analysis; Cardiology. Vascular system; Computer Science; Delayed Graft Function - diagnosis; Delayed Graft Function - physiopathology; Graft failure; Heart - physiopathology; Heart Transplantation; Humans; Imaging; Life Sciences; Magnetic Resonance Spectroscopy - methods; Medical Imaging; Medical sciences; Middle Aged; Phosphocreatine - analysis; Phosphorus Isotopes; Phosphorus magnetic resonance spectroscopy; Pilot Projects; Pneumology; Predictive Value of Tests; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the heart
• ISSN: 1010-7940; 1873-734X
• DOI: 10.1016/j.ejcts.2005.07.009

Objective: Early graft failure (EGF) is a life-threatening event still accounting for a significant percentage of early deaths after heart transplantation. We tested whether selected metabolic markers, including high-energy phosphate concentrations measured ex vivo in pre-transplant heart grafts by 31P magnetic resonance spectroscopy (MRS) are related with early post-transplant outcome. Methods: During a 3-year period, 26 heart grafts harvested in the vicinity of the transplantation centre were studied. Evaluation of transplantability was done conventionally. 31P MRS was performed ex vivo approximately 60min after aortic cross-clamp to quantify ATP, Pi and PCr concentration ratios. A MRS-score was defined as a combination of intracellular pH (pHi) and the PCr/Pi ratio. EGF was defined as the need to abnormally extend circulatory support or to use more than two inotropes before weaning the patient from CPB after transplantation. The grafts were attributed to three groups as follows: A1, transplanted with uneventful outcome (n=14); A2, transplanted with subsequent EGF (n=3) and B, not suitable for transplantation (n=9). Results: Significant differences between groups existed for the following metabolic markers: PCr/ATP (P=0.013), PCr/Pi (P=0.0004), pHi (P=0.0016) and MRS-score (P=0.0001). The sensitivity, specificity and positive likelihood ratio for EGF with a MRS-score≦1.95 were, respectively, 100%, 86% and 7. Conclusions: In the setting of this study, post-transplant outcome was related to the pre-transplant MRS-score of grafts evaluated ex vivo. This result might help to more securely use grafts from marginal donors.