A New Method of Assessing Myocardial Ischemic Injury During Cardiac Operations: Electron Probe X-Ray Microanalysis

Ischemia leads to breakdown of the energy supply in the cell and to depression of the Na-K-ATPase activity [6]. Consequently active transport mechanisms are inhibited, with a tendency towards equilibration of the intracellular components with the constituents of the volume-limited extracellular space [5]. Because of their low molecular weights, the elements are likely to be the determining equilibration factors. Intracellular element assay can therefore be used to provide information about the changes in the composition and concentration of the intracellular elements. If it is combined with extracellular element assay, the intracellular element profile should furnish information about the integrity of the cells and their membranes. Electron probe X-ray microanalysis is a one-stage analytical method avoiding the errors inherent in a multistage procedure. The following elements can be assayed: calcium (Ca), sodium (Na), phosphorus (P), sulfur (S), chlorine (C1), potassium (K), and magnesium (Mg).