We report a 30-year-old woman who developed an acute myocardial infarc
tion at 24 weeks of gestation. She did not undergo any kind of acute i
ntervention. On the 8th hospital day, premature delivery was performed
safely following premature rupture of membrane, Coronary angiogram wa
s normal and no spasm was induced by provocative test with ergometrine
maleate. The patient had abnormal values of fibrinogen, thrombin-anti
thrombin III complex and plasmin-alpha(2)-plasmin inhibitor complex. T
hus, thrombus formation might have been associated with the onset of a
cute myocardial infarction. This is the first case of acute myocardial
infarction during pregnancy, showing normal coronary angiogram and ne
gative pharmacological provocation of coronary spasm.