<prompt> Myocardial isonzyme of CK which is specific for myocardial infarction isCK-BBCK-MBCK-MMAll of the above  <response>: within 46 hrs after development of acute MI, peaks during the 2nd day 4 fold rise and disappears in 23 days. Other causes of total CK elevation:1. Skeletal diseases Polymyositis, Muscle dys- trophy, Myopathies 2. Electrical cardioversion3. Skeletal muscle damage trauma, convulsions, immobilisation 4. Hypothyroidism 5. Stroke 6. Surgery b. AST: Starts rising on the 1st day, peaks in 23 days 3 fold rise and disappears by 3rd day. c. LDH1: Starts rising by second day, peaks around 3 4 days 3 fold rise and disappears in 10 days. d. Troponin T: Cardiac troponin T is a regulatory contractile protein not normally found in blood. Its detection in the circulation has been shown to be a sensitive and specific marker for myocardial cell damage. Troponin T and I reach a reliable diagnostic level in plasma by 12-16 hrs, maximal activity by 24-32 hrs, returns to normal in 10-12 days. Troponin I : 0-0.4 ngml Troponin T: 0-0.1 ngml Cardiac troponins are detected in the serum by using monoclonal antibodies. These antibodies have negligible cross reactivity to skeletal muscle. Cardiac troponins I and T start to rise within 3-4 hours after myocardial infarction and remain raised for 4-10 days 