Background: The occurrence of congestive heart failure (CHF) during hospitalization for acute myocardial infarction (AMI) is an important factor influencing morbidity and mortality. AMI is frequently associated with leukocytosis. Studies have shown that the cytokines released from neutrophils have negative inotropic effects and hence, contribute to the development of CHF. This study aims to determine if there is an association between absolute neutrophil count (ANC) on admission of patients with AMI and the development of early on-set CHF in such patients.
Design And Setting: Retrospective, case-control study at Philippine Heart Center (PHC), tertiary medical center. Patients: A total of 152 patients discharged with a diagnosis of AMI who presented initially as Killip 1 on admission between January 1, 1996 to December 31, 2000, were included. Main Outcome Measure: Development o CHF within 4 days from hospital admission documented in the medical records as clinical symptoms (progression to Killip 2, 3 or 4) confirmed by chest radiologic and/or echocardiographic findings.
Results: Statistical analyses were performed to examine the relation between the ANC and the development of CHF in the first 4 days after AMI while controlling for baseline characteristics and therapeutic interventions. The mean ANC is 12.3 +/-0.5 X 109/L in the group of patients who developed CHF compared with 7.8 +/-0.3 X 109/L in those who did not. Multivariable analysis revealed a significant correlation with increasing ANC and subsequent development (adj. OR = 10.8; 95% Cl = 5.08-22.97). Other factors found to have stong association with development of CHF are the presence of diabetes mellitus (adj. OR = 2.48; 95% Cl=1.44, 5.38) and use the nitrates (adj. OR = 3.12 95% Cl=1.5-6.47). Subgroup analysis further revealed that ANC is directly correlated with Killip class on day 4 (r = 0.565; p < 0.001).
Conclusion: High ANC on admission in patients with AMI is associated with the early develoment of CHF, which may help in the identification of high risk patients who might benefit from more aggresive interventions to prevent f reduce the risk of CHF.