Objectives: Serum deoxyribonuclease I (DNase I) activity has recently been highlighted as a potential diagnostic marker for the early detection of an acute myocardial infarction (AMI). We evaluated whether the serum DNase I activity was associated with the parameters of the left ventricular (LV) remodeling after an AMI.
Methods: We measured the serum DNase I activity in 45 patients with an AMI who were admitted to our hospital within approximately 4 h of the onset of their chest pain. We also evaluated the LV ejection fraction (LVEF), LV end-diastolic volume (LVEDV), and LV end-systolic volume (LVESV) of each patient by echocardiography at the time of admission and at 6 months after the onset of the AMI.
Results: The serum DNase I activity peaked at 3.5+/-2.0 h after the onset of the symptoms in the patients with an AMI, thereafter exhibiting a time-dependent decline within 12 h, and a return to the basal level within 24 h in almost all cases. Neither the LVEF, LVEDV, nor LVESV in each patient on admission exhibited a significant correlation to the peak levels of the serum DNase I activity. Although there was no correlation between the peak DNase I activity and LVEF at 6 months after the onset, a significant positive correlation of the peak DNase I activity with LVEDV and LVESV (r=0.48, p<0.001 and r=0.34, p=0.02, respectively) was found. Furthermore, the LVEDV at 6 months after the onset in the high DNase I activity group (> 17.9 U/L) were significantly higher than those in the low DNase I activity group (< or = 17.9 U/L) (118.0+/-28.2 ml vs 89.3+/-25.4 ml, p=0.026).
Conclusions: The serum DNase I activity level may predict LV enlargement associated with remodeling after an AMI.