Early pronounced ST segment depression with marked J point decline heralding acute lethal clinical myocardial...

Marked ST segment depression (greater than or equal to 2 mm J point decline with horizontal or downsloping ST) was correlated with necropsy findings in 105 cases. Acute myocardial infarction (AMI) was most frequently (70%) responsible for development of the abnormal ST pattern, thereby indicating the diagnosis and severe prognosis of the AMI. In 23% of patients the ST segment depression pattern was associated with chronic heart disease without AMI; all were severely ill with 92% receiving digitalis. Sudden worsening of the basic heart disease or circulatory shock were frequently found to coincide with the abnormal ST pattern; necropsy revealed extensive old MI or myocardial fibrosis in these patients. Marked ST segment depression was also found in five patients without underlying heart disease at autopsy; an acute cerebral accident or circulatory shock was considered to have produced the abnormal ST segment pattern.