Choice of cardioplegia influences metabolomics of human cardiac tissue

Cardioplegia is often used prior to acquisition of human cardiac tissue to minimize warm ischemia time, which can severely confound studies of cardiac metabolism. However, there are several choices of cardioplegia solutions, and whether these solutions differentially impact tissue metabolism or metabolomic studies is not known. Here, we perform untargeted metabolomics, using both liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry, on a large cohort of hearts transplanted for cardiomyopathy or from gift-of-life donors, and who have received different cardioplegia solutions. We show that different cardioplegia solutions distinctly impact cardiac metabolism and tissue metabolomic studies. Notably, these differences are mild relative to those seen comparing failing to nonfailing hearts, and identification of cardioplegia components in mass spectra should enable rigorous interpretation of changes between conditions. These data demonstrate how cardioplegia solutions may influence cardiac metabolism in human heart samples and underscore the need to report specific details of cardioplegia solution use in studies of human cardiac metabolism.