Association of plasma concentration of small heat shock protein B7 with acute coronary syndrome

Background: Heat shock proteins (HSPs) act as chaperones and have a protective function in cardiovascular diseases. The clinical association of a novel small HSPB7 with cardiovascular disease, however, has not been reported. The aim of this study was to investigate the potential biological functions of HSPB7 and its relationship with acute coronary syndrome (ACS). Methods and Results: A mouse myocardial infarction (MI) model and samples from clinical human subjects were used to determine plasma HSPB7 concentration after acute MI. The associations of plasma HSPB7 concentration with ACS and other risk factors of coronary artery disease were analyzed. Plasma HSPB7 concentration was found to be rapidly elevated in mice after coronary artery ligation. In addition, plasma HSPB7 concentration was significantly higher in patients with ACS than in control patients with non-cardiac chest pain (5.1 ng/ml vs. 2.9 ng/ml, P<0.001). Plasma HSPB7 was detected as early as 1-3 h after the onset of symptoms and remained detectable up to 24 h. Furthermore, in patients presenting to the emergency department with acute chest pain, HSPB7 level was an independent risk factor of ACS (adjusted odds ratio, 7.44; 95% confidence interval: 1.91-28.93, P<0.01). Conclusions: HSPB7 is a potential early biomarker after MI and serves as an independent risk factor of ACS in patients with acute chest pain.