D-dimer as a marker of severity of myocardial infarction

We measured D-dimer levels in 40 STEMI and 40 NSTEMI patients. All patients of STEMI had increase in D-dimer, while significant amount of increase in D-dimer was seen in NSTEMI patients. Between the two groups, elevation was more in STEMI group. Mean D-dimer values of STEMI group were 461.37, and for NSTEMI, it was 412.28; standard deviation for both the groups was 122.16 and 127.04, respectively. The standard error of difference between the two means was 4.40, while the actual difference between the two means was 49.08, which is twice the standard error of difference between the two means, which is highly significant. Applying unpaired Student's t test, the value comes to 0.00057 (p < 0.05), which is highly significant. In STEMI, 3 patients with D-dimer levels 650–750 and 1 patient with D-dimer level of 550–650 had no resolution of ST elevation. Thus, high D-dimer levels have worse outcomes on ST segment elevation resolution. There were 7 deaths in STEMI group, out of which 5 had their D-dimer in more than 550 range (significantly raised), while there were 4 deaths in non-STEMI group, which had their D-dimer in 450–550 range (highest levels among non-STEMI group). Thus, high levels of D-dimer were associated with high levels of mortality. STEMI has worse outcome than NSTEMI. Also, in STEMI, high D-dimers levels have worse outcome on ST segment elevation resolution and carry high levels of mortality. Thus, D-dimer is significant marker for severity of MI.