Neutrophilia and congestive heart failure after acute myocardial infarction

Background inflammation associated with acute myocardial infarction (AMI) i s frequently marked by a peripheral leukocytosis and relative neutrophilia. Whether this process may contribute to the development of postinfarction c ongestive heart failure (CHF) is not established. The objective of this stu dy was to examine the association between hospital admission peripheral tot al leukocyte count and the neutrophil percentage and the subsequent develop ment of CHF in patients with AMI. The study was designed as a retrospective cohort study in the setting of a tertiary referral hospital. Participants included 185 patients discharged with a diagnosis of AM[ between May 1 and Sept 30, 1996. Methods and Results outcome measures included clinical episodes of CHF with confirmatory chest roentgenogram findings and/or echocardiographic evidenc e of contractile dysfunction. Multivariable logistic regression analyses we re performed to examine the relation between the total leukocyte count, neu trophil percentage, and the development of CHF in the first 4 days after AM I while controlling for baseline characteristics and early therapeutic inte rventions. Thirty-one percent of the cohort had a leukocyte count >11.0 x 1 0(9)/L on admission to the hospital; 65% had a neutrophil percentage >65%, and 61% had a lymphocyte percentage less than or equal to 25%. CHF develope d in 43% of the cohort. Of these, 92.5% had relative neutrophilia (neutroph il percentage >65%) compared with 45% of those in whom CHF did not develop. Multivariable analysis revealed a highly significant association between r elative neutrophilia and the subsequent development of CHF (odds ratio 14.3 ; 95% confidence interval 5.2 to 39.3). Conclusions Relative neutrophilia on admission to the hospital in patients with AMI is significantly associated with the early development of CHF. Thi s association may help in the identification of individuals at high risk wh o might benefit from more aggressive interventions to prevent or reduce the risk of CHF.