The nitroblue-tetrazolium test following acute myocardial infarction.

The percentage nitroblue-tetrazolium (NBT) leucocyte levels were evaluated daily in the 10 days following a first attack of coronary thrombosis. In 12 uncomplicated cases the peak increase was on the second or third day; thereafter the level declined and was below 10% by the tenth day. Three other patients did not conform to this pattern of NBT behaviour. They had experienced a second myocardial infarction and this was attended by a secondary rise in the NBT score; in the two survivors the score remained elevated on the tenth day. Comparison of the score on the second-third and tenth-fourteenth days is a possible useful index of a further complication.