Predictive Factors for Heart Failure in Patients with Unstable Angina and Acute Non-ST Elevation Myocardial Infarction

ABSTRACT

BACKGROUND AND OBJECTIVES: Besides the acute coronary syndrome (ACS), the left ventricular failure (LVF) is the next important determinant of morbidity and mortality after acute coronary syndrome (ACS). The prediction of high risk groups for LVF may be in the initial management of patients with unstable angina (UA) or acute non-ST elevation myocardial infarction (NSTEMI). SUBJECTS AND METHODS: 179 patients (60.4+/-11.6 years, 121 male) who underwent diagnostic coronary angiography under the diagnosis of UA/NSTEMI between January and December, 2000, in the Chonnam National University Hospital Heart Center were enrolled for evaluation of relationship between the development LVF and various parameters, including clinical features, initial electrocardiogram, laboratory findings and coronary angiographic findings. RESULTS: Unstable angina was clinically diagnosed in 124 patients, and NSTEMI in 55 patients. During a 12-month follow-up period, less than 40% of the left ventricular ejection fraction (EF), a low amount, was observed in 28 patients (15.7%). In diabetic patients, the incidence of LVF was significantly higher than in non-diabetics (p<0.05). Patients with elevated C-reactive protein (CRP) or positive troponin I had LVF more frequently (p<0.05). On the initial electrocardiogram, the total summation of ST segment change inversely correlated with EF (p<0.05). Patients whose QT dispersion was longer than 80 ms had a higher incidence of LVF (p<0.05). Coronary angiographic findings of total occlusion correlated with the development of LVF (p<0.05), but not with other characteristics. On multiple logistic regression analysis, high CRP level (p=0.024), summation of ST change (p=0.021), total occlusion of the coronary artery (p=0.008) were independent prognostic factors of LVF. CONCLUSION: Elevated CRP, summation of ST change and total coronary artery occlusion are important predictive factors for LVF in UA/NSTEMI.