Clinical Chemistry, Vol 29, 1727-1730, Copyright © 1983 by American Association for Clinical Chemistry

Cathodal bands in electrophoretograms of creatine kinase isoenzymes in serum collected after cardiac surgery: a poor prognostic sign

AA Keshgegian and BL Marchant

Of 708 patients who had undergone cardiac surgery, the serum of 23 showed one or two enzyme bands cathodal to CK-MM in creatine kinase (CK) isoenzyme electrophoretograms. Postoperative mortality rate during hospitalization was: no bands, 8.8%; one band, 13%, two bands, 63% (p less than 0.001). Patients whose sera showed cathodal bands were slightly older than those without, and their postoperative serum lactate dehydrogenase (LD) activity was greater, with very high proportions of LD 5. The two cathodal bands in patients who died differed in cathodal electrophoretic mobility from the two bands in survivors, implying that different enzyme forms were involved. All cathodal bands were inhibited by reagent containing diadenosine pentaphosphate, as was adenylate kinase from erythrocytes and liver cytoplasm. Mitochondrial CK from liver and presumed mitochondrial CK in serum from a patient with malignancy were not inhibited. We conclude that the appearance of two enzyme bands cathodal to CK-MM, probably representing adenylate kinase and possibly originating from various tissues, is associated with a poor prognosis in patients after cardiac surgery.