title: Sympathetic nervous activity in patients with acute coronary syndrome: a comparative study of inflammatory biomarkers.
abstract: Previous studies have shown that both sympathetic hyperactivity and enhanced inflammatory responses are associated with poor outcomes in patients with acute coronary syndrome (ACS). Whether there is a correlation between these two characteristics remains unclear. Thirty-four patients with uncomplicated ACS were evaluated; their mean age was 51.7±7.0 years, 79.4% were male, and 94.1% had myocardial infarction (MI). On the fourth day of hospitalization, they underwent muscle sympathetic nerve activity (MSNA) analysis (microneurography), as well as ultrasensitive C-reactive protein (usCRP), interleukin-6 (IL-6), and lipoprotein-associated phospholipase A2(Lp-PLA2) activity measurements. These evaluations were repeated at 1, 3, and 6 months after hospitalization. Both MSNA and inflammatory biomarkers were elevated during the acute phase of ACS and then decreased over time. At hospitalization, the median usCRP level was 17.75 (IQR 8.57; 40.15) mg/l, the median IL-6 level was 6.65 (IQR 4.45; 8.20), the mean Lp-PLA2activity level was 185.8 ±52.2 nmol/min per ml, and mean MSNA was 64.2±19.3 bursts/100 heart beats. All of these variables decreased significantly over 6 months compared with the in-hospital levels. MSNA was independently associated with the peak level of creatine kinase isoenzyme MB (CKMB) in the acute phase (P=0.027) and with left ventricular ejection fraction (LVEF) at 6 months (P=0.026). Despite the increased levels of inflammatory biomarkers and sympathetic hyperactivity in the initial phase of ACS, no significant correlations between them were observed in any of the analyzed phases. Our data suggest that although both sympathetic hyperactivity and inflammation are concomitantly present during the early phase of ACS, these characteristics manifest via distinct pathological pathways.
authors.affiliation: Heart Institute (InCor)-University of São Paulo Medical School, São Paulo, SP, Brazil humbertograner@uol.com.br.
authors.forename: Humberto G
authors.initials: HG
authors.lastname: Moreira
authors.affiliation: Heart Institute (InCor)-University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: Rony L
authors.initials: RL
authors.lastname: Lage
authors.affiliation: Heart Institute (InCor)-University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Martinez
authors.affiliation: Heart Institute (InCor)-University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: Larissa
authors.initials: L
authors.lastname: Ferreira-Santos
authors.affiliation: School of Physical Education and Sports, University of São Paulo, SP, Brazil.
authors.forename: Maria U P B
authors.initials: MUPB
authors.lastname: Rondon
authors.affiliation: Heart Institute (InCor)-University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Negrão
authors.affiliation: Heart Institute (InCor)-University of São Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: José C
authors.initials: JC
authors.lastname: Nicolau
mesh_terms: D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000097:blood; D054058:Acute Coronary Syndrome / Q000097:blood / Q000503:physiopathology*; D000328:Adult; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism; D052279:Creatine Kinase, MB Form / Q000097:blood; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000503:physiopathology*; D018836:Inflammation Mediators / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000503:physiopathology; D013564:Sympathetic Nervous System / Q000503:physiopathology*
chemical_list: D015415:Biomarkers; D018836:Inflammation Mediators; D015850:Interleukin-6; D002097:C-Reactive Protein; D052279:Creatine Kinase, MB Form; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase
keywords: C-reactive protein; acute coronary syndromes; biomarkers; inflammation; interleukin-6; sympathetic nervous system