Increased CK-BB concentrations in serum following cardiac surgery.

We measured the BB isoenzyme of creatine kinase by a specific radioimmunoassay in the serum of 47 patients following cardiac surgery. A sharp increase in CK-BB occurred immediately after surgery, with rapid return to baseline by the fourth post-operative day. This data, along with other reports in the literature, suggest that CK-BB is released into the circulation following myocardial insult.