Neutrophil to lymphocyte ratio in acute ST-segment elevation myocardial infarction.

BACKGROUND: Spontaneous early patency of infarct-related artery (IRA) on arrival for primary percutaneous coronary intervention is associated with better short- and long-term prognosis in patients with ST-segment elevation myocardial infarction (STEMI). We aimed to investigate whether the hemographic parameters on admission are associated with spontaneous IRA patency.

METHODS: This was a retrospective study of 1,625 patients with acute STEMI who underwent primary percutaneous coronary intervention<12 hours after the onset of symptoms.

RESULTS: Angiography showed patent IRA (prethrombolysis in myocardial infarction [TIMI] grade 3 flow) in 160 (9.8%) patients. Neutrophil count on admission (7.8±2.4×10³/μL versus 9.7±3.8×10³/μL; P<0.001) was significantly lower and lymphocyte count (2.4±1.0×10³/μL versus 1.9±1.1×10³/μL; P<0.001) on admission was significantly higher in the patent IRA group. Neutrophil to lymphocyte ratio (NLR) was significantly lower in the patent IRA group (4.1±3.2 versus 6.9±5.5; P<0.001). Admission leukocyte counts (13±4.0×10³/μL versus 12±3.4×10³/μL; P<0.001) and NLR (7.2±5.8 versus 5.5±4.4; P<0.001) of the patients with TIMI thrombus score≥4 were significantly higher than patients with TIMI thrombus score<4. In the multivariate analysis, NLR≥4.5 (3.17 [95% confidence interval: 2.04-4.92]; P<0.001) was found to be independently predicting an occluded IRA on initial angiography with a sensitivity of 62.7% and a specificity of 70%.

CONCLUSIONS: NLR on admission is significantly related to angiographic thrombus burden and spontaneous early IRA patency in patients with acute STEMI.