<prompt> Which one of the following isoenzyme variants of Creatine kinase is elevated in myocardial infarctionCK-BBCK-MBCK-MMAll the above  <response>: Tissue injury that results in damage to cell membranes and an increase in the permeability of the plasma membrane leads to leakage of intracellular material into the bloodstream eg, leakage of Creatine kinase MB into the bloodstream following a myocardial infarction. Reference: Explanation: Harpers Biochemistry; 30th edition; Chapter 48; Clinical Biochemistry 