Coronary Artery Disease
Comparison of the prognostic value of C-Reactive protein and troponin I in patients with unstable angina pectoris

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Abstract

This study assessed the prognostic value of cardiac troponin I (cTnI) and C-reactive protein (CRP) in unstable angina, and specifically in patients with angiographically proven coronary artery disease. These biochemical parameters, which are related to myocardial injury or to systemic inflammation, may help in short-term risk stratification of unstable angina. We prospectively studied 195 patients with unstable angina, 100 of whom had angiographically proven coronary artery disease (with normal creatine kinase [CK] and CK-MB mass). Serum concentrations of cTnI (N <0.4 ng/ml) and CRP (N <3 mg/L) were measured at admission, 12, and 24 hours later. The rate of in-hospital major adverse cardiac events (death, myocardial infarction, or emergency revascularization) was higher in patients with increased cTnI within the first 24 hours, regardless of the results of coronary angiography (23% vs 7%; p <0.001). Conversely, events occurred at similar rates in patients with or without increased CRP. In patients with angiographic evidence of coronary artery disease, multivariate analysis showed that increased cTnI within 24 hours of admission (35 patients) was an independent predictor of major adverse cardiac events (odds ratio 6.7, range 1.7 to 27.3), but not cTnI levels at admission and CRP at 0, 12, and 24 hours. Thus, both in unselected patients with unstable angina and in patients with angiographically proven coronary artery disease, increased cTnI within 24 hours of admission, but not CRP, is a predictor of in-hospital clinical outcome. We also found a temporal link between cTnI increase and late elevation of CRP, suggesting that systemic inflammation may partially be a consequence of myocardial injury.

Section snippets

Patient group

Three hundred nine consecutive patients admitted to the coronary care unit of Hôpital Bichat with a clinical diagnosis of unstable angina, defined as angina at rest, recent onset, or crescendo angina (<4 weeks) with chest pain within the previous 48 hours, were considered eligible for the study. Patients with myocardial infarction at admission (total creatinine kinase [CK] >2 times above normal and increased CK-MB isoenzyme mass during the first 48 hours) (n = 43) or with myocardial infarction

Unselected unstable angina population

In the study population (n = 195), elevated cTnI, but not elevated CRP, within 24 hours of admission was predictive for major adverse cardiac events, myocardial infarction or death, and myocardial infarction (Table I). In patients with normal cTnI values within the first 24 hours, the frequency of major adverse cardiac events was similar in patients with (n = 73) or without (n = 62) elevated CRP (≥6 mg/L) within 24 hours (7% vs 6%, NS).

Clinical characteristics and in-hospital outcome

Patients’ mean age was 61 ± 1 years; 75% were men. A

Discussion

Treatment of unstable angina should ideally be tailored to the short-term risk of major adverse cardiac events. Recurrent ischemia in patients receiving medical therapy is associated with a poor prognosis.1, 2 In our study, we demonstrated that recurrent ischemia was a strong predictor for in-hospital adverse events. However, earlier parameters are needed for decision making. Markers of myocardial injury, such as troponins I and T, may be elevated in the absence of other signs of myocardial

Acknowledgements

The authors are grateful to DADE laboratories (Massy, France) for supplying the cardiac troponin I assay kits and are indebted to the personnel of the Coronary Care Unit and the nurses of the catheterization laboratory.

References (23)

  • Effects of tissue plasminogen activator and a comparision of early and conservative strategies in unstable angina and non-Q wave myocardial infarctionresults of the TIMI IIIB trial

    Circulation

    (1994)
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    This study was supported in part by a grant from the Fédération Française de Cardiologie, Paris, France.

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