Regarding MI, the levels of which one of the listed begin to increase 4 to 6 h after the onset of chest pain, reach maximal serum concentration in about 12 to 24 h, and remain elevated for about 3 to 10 days?
Explanation
Answer: D - Serum enzymes that may be elevated after an MI include troponin, CPK, SGOT (AGT), and LDH, which are increased temporally in that order. The troponin complex is made up of three protein subunits: troponin I (Tn-I), troponin T, and troponin C- There are three isoforms of Tn-I: two in skeletal muscle and one in cardiac muscle (cTn-I). cTn-I levels begin to increase 4 to 6 h after the onset of chest pain, reach maximal serum concentration in about 12 to 24 h, and remain elevated for about 3 to 10 days.
