Chonnam Med J.  2011 Apr;47(1):20-26. 10.4068/cmj.2011.47.1.20.

A Novel Risk Stratification Model for Patients with Non-ST Elevation Myocardial Infarction in the Korea Acute Myocardial Infarction Registry (KAMIR): Limitation of the TIMI Risk Scoring System

• Kim JH
• Jeong MH
• Ahn Y
• Kim YJ
• Chae SC
• Seong IW
• Kim CJ
• Cho MC
• Seung KB
• Park SJ
• Other Korea Acute Myocardial Infarction Registry (KAMIR) Investigators

• KMID: 2172240
• DOI: http://doi.org/10.4068/cmj.2011.47.1.20

Abstract

The Thrombolysis in Myocardial Infarction (TIMI) risk score (TRS) has proven value in predicting prognosis in unstable angina/non ST-elevation myocardial infarction (NSTEMI) as well as in ST-elevation myocardial infarction. The TRS system has little implication, however, in the extent of myocardial damage in high-risk patients with NSTEMI. A total of 1621 patients (63.6+/-12.2 years; 1043 males) with NSTEMI were enrolled in the Korea Acute Myocardial Infarction Registry (KAMIR). We analyzed the risk for major adverse cardiac events (MACE) during a 6-month follow-up period. The TRS system showed good correlation with MACE for patients in the low and intermediate groups but had poor correlation when the high-risk group was included (p=0.128). The MACE rate was 3.8% for TRS 1, 9.4% for TRS 2, 10.7% for TRS 3, and 12.3% for TRS 4 (HR=1.29, p=0.026). Among the biomarkers and clinical risk factors, elevated N-terminal pro-brain natriuretic peptide (NT-proBNP) (HR=2.61, p=0.001) and Killip class above III showed good correlation with MACE (HR=0.302, p<0.001). Therefore, we revised an alternative clinical scoring system by including these two variables that reflect left ventricular dysfunction: age > 65 years, history of ischemic heart disease, Killip class above III, and elevated pro-BNP levels above the 75th percentile. This modified scoring system, when tested for validity, showed good predictive value for MACE (HR=1.64, p<0.001). Compared with the traditional TRS, the novel alternative scoring system based on age, history of ischemic heart disease, Killip class, and NT-proBNP showed a better predictive value for 6-month MACE in high-risk patients with NSTEMI.

Keyword

Angina, unstable; Mortality; Myocardial Infarction

MeSH Terms

Angina, Unstable
Biomarkers
Follow-Up Studies
Humans
Korea
Myocardial Infarction
Myocardial Ischemia
Natriuretic Peptide, Brain
Peptide Fragments
Prognosis
Risk Factors
Natriuretic Peptide, Brain
Peptide Fragments

Figure

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  FIG. 1 Major adverse cardiac event (MACE)-free survival according to the TIMI Risk Score.

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  FIG. 2 Major adverse cardiac event (MACE)-free survival according to the Modified TIMI Risk Score system.

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