Detection of brain cardiolipins in plasma after cardiac arrest

Neurological injury resulting from dysfunction of brain mitochondria limits recovery after cardiac arrest (CA). Available indicators of neurological injury are inadequate for early prognostication after return of spontaneous circulation (ROSC). High diversification and essentiality of brain mitochondrial cardiolipins (CL) makes them unique candidates to quantify brain injury and predict prognosis early after ROSC. Using high-resolution liquid chromatography mass spectrometry, we determined CL content in plasma from 39 patients within 6 h of ROSC, 10 healthy controls and human heart and brain tissue. Cerebral score (C-score) was derived from brain-specific CL. Using a rat model of CA, CL was quantified in plasma and brain and results were compared with the controls. Brain and heart fell on extreme ends of CL diversity spectrum. Nine of 26 brain-specific CL were detected in plasma and correlated with brain injury. The C-score correlated with early neurologic injury and predicted neurologic outcome. In a rat CA model, a significant reduction in hippocampal CL content corresponded to CL released from the brain into systemic circulation. In conclusion brain-specific CL species accumulate in plasma after CA and can be used to predict injury severity and outcome.