Neutrophil Counts Help Predict Free Wall Rupture Following St-elevation Myocardial Infarction.

Purpose: Free wall rupture (FWR) is a lethal complication after acute myocardial infarction; however, the un-derlying mechanisms of FWR are unclear. This study analyzes the relationship between neutrophil counts and FWR following ST-elevation myocardial infarction (STEMI).

Methods: The case group was STEMI patients with FWR and the control group was STEMI patients without FWR (case-control ratio was 1:4). The demographic data, clinical manifestation and laboratory test results were retrospectively collected and analyzed.

Results: Of a total of 6,712 consecutive STEMI patients, 78 patients (1.2%) had FWR. Compared with STEMI patients, patients with FWR were older and more likely to be female with an anterior infarct. White blood cell (WBC) counts were significantly higher in the FWR group. Moreover, we found that the elevated neutrophil counts mainly accounted for the elevated WBC counts. There was also a correlation between the age and neu-trophil counts (P=0.0109); as patient age increased, neutrophil counts decreased (P=0.0387). We also found no correlation between neutrophil counts and the time between myocardial infarction attack and FWR; however, when dividing these patients into FWR ≤48 h after admission to hospital for STEMI and FWR >48 h, there was a significant difference in neutrophil counts (P=0.0196). Furthermore, the results of logistic regression analy-sis showed that increased neutrophil was an independent risk factor for FWR (odds ratio: 2.404, confidence interval: 1.055-5.477).

Conclusion: Elevated neutrophil counts were found to be the main cause of differences in WBC counts be-tween FWR and STEMI. Elevated neutrophil was an independent risk factor for FWR. This study provided clues for further research and development of therapeutics for the prevention of FWR.