The long-term clinical significance of troponin and electrocardiogram in patients with unstable angina

Lee, Sang Hyun; Jeong, Myung Ho; Park, Jong Soo; Kim, Weon; Kim, Kye Hun; Kang, Kyung Tae; Rhew, Jay Young; Park, Jong Cheol; Ahn, Young Keun; Cho, Jeong Gwan; Park, Jong Chun; Suh, Soon Pal; Ahn, Byoung Hee; Kim, Sang Hyung; Kang, Jung Chaee

Abstract

BACKGROUND: The early assessment of cardiac risk is important in patients with unstable angina (UA). The present study investigates the prognostic value capacities of cardiac specific troponin T (cTnT), cardiac specific troponin I (cTnI) and ECG change in Korean patients with UA.
METHODS
Two hundred thirty patients (61+/-11 year, male:female=172:58) admitted to Chonnam National University Hospital via emergency room under the diagnosis of UA and underwent diagnostic coronary angiography (CAG) between July 1998 and June 1999, were analyzed according to the ECG findings of ST depression (STD), T wave inversion (TWI), cTnT and cTnI. Clinical characteristics, initial and follow-up CAG findings, and major adverse cardiac events (MACE) within one year were compared.
RESULTS
Among the enrolled patients, 164 (71.3%) patients had significant coronary artery stenosis (CAS). During the one-year follow-up period, 40 patients developed MACE : 2 patients died, 7 patients had acute myocardial infarction and 34 patients developed restenosis. Positivity of cTnT and cTnI was associated with presence of CAS (p<0.001) and multi-vessel diseases (p<0.001). Levels of cTnT (5.7+/-8.4 vs 1.6+/-3.1 mg/dL, p<0.001) and cTnI (0.11+/-0.18 vs 0.03+/-0.19 mg/dL, p<0.001) were associated with MACE. The presence of STD was associated with the presence of CAS (p<0.001), multi-vessel diseases (p<0.001), low Thrombolysis In Myocardial Infarction (TIMI) flow (p<0.01), ACC/AHA types (p<0.001) and MACE (p<0.05). TWI was associated with TIMI flow (p<0.05), ACC/AHA types (p<0.001). In the patients with negative cTnT or cTnI, the negative predictive value of MACE within 1 year was 87.1% and 93.4%, respectively. In the absence of STD, that of MACE within 1 year was 87.1%.
CONCLUSION
The level of troponin and electrocardiograhic findings are valuable in the early stratification of cardiac risks in Korean patients with UA and the prediction of MACE.