Serum dopamine beta-hydroxylase (DBH) activity in acute myocardial infarction.

Serial serum dopamine beta-hydroxylase (DBH) activities were determined in 32 patients admitted to the Coronary Care Unit with chest pain, 9 with acute myocardial infarction and 23 with other diagnoses. The values of DBH were elevated in both groups on day one. The acute myocardial infarction group showed a slower decline and reached a baseline plateau at day five when compared to the control group whose values fell significantly by day two. The reason for the quantitative difference between the two groups is speculative and may be related to changes in plasma volume. Increases in DBH are not specific for myocardial infarction but a nonspecific responses to stress.