Detection of elevated succinate in brain during circulatory arrest in a piglet model: A 3TH MR spectroscopy study.

Abstract

PURPOSE: To measure and validate elevated succinate in brain during circulatory arrest in a piglet model of cardiopulmonary bypass. METHODS: Using data from an archive of 3TH MR spectra acquired in previous in-magnet studies, dynamic plots of succinate, spectral simulations and difference spectra were generated for analysis and validation. RESULTS: Elevation of succinate during circulatory arrest was observed and validated. Fitting bias was evaluated as a function of the line-widths and signal-to-noise ratios of the archived data. Succinate increases were independent of bypass temperature. Succinate elevation was also not observed with antegrade cerebral perfusion. CONCLUSION: Although spectrally overlapped and at sub-millimolar levels, elevated brain succinate can be reliably measured by dynamic MR spectroscopy at 3T. Noise dependent bias of the stronger overlapping signals did not impact the succinate measurement. Elevated succinate during circulatory arrest and its recovery after reperfusion was observed. This finding is consistent with earlier reports that correlate elevated succinate with ischemic-reperfusion injury.