BACKGROUND The value of clinical predictors of left ventricle function recovery after surgical revascularization in patients with decreased ejection fraction is well documented. However, there are no clinical studies assessing factors which can influence left ventricle function in patients with coronary disease and low ejection fraction (LVEF) undergoing percutaneous coronary interventions (PCI). OBJECTIVE We tried to assess clinical prognostic factors of left ventricle function improvement after PCI in patients with coronary artery disease and impaired LVEF. PATIENTS AND METHODS We studied patients with LVEF < 45% undergoing PCI. We assessed duration and grade of symptoms of heart failure, angina class and echocardiographic parameters of LV systolic function. After 6 months follow-up LVEF was obtained again. We analyzed influence of baseline clinical factors on LVEF recovery after PCI. RESULTS We studied 29 patients (mean age 54.4 +/- 11 years) before and after PCI. In the whole group of patients we found significant increase in EF (38.4 +/- 6% vs 50.4 +/- 15%, p = 0.005) at follow up examination. There was significant improvement of EF in patients with NYHA class I or II (from 40.4 +/- 5% to 58.1 +/- 9%, p < 0.0001) as compared to NYHA class III or IV (from 31.4% +/- 9% to 31.8 +/- 11, p = NS). In multivariate regression analysis correlation between NYHA class and LVEF at control examination (beta = -0.54, p = 0.03) was independent from epidemiological variables and baseline LVEF. There was significant increase in LVEF in patients with severe angina (CCS III or IV) as compared to patients without angina (DEF 21.3 +/- 5% vs 7.9 +/- 10%, p = 0.009). There was also higher increase in LVEF in patients with chest pain during balloon inflation (delta EF 17.4 +/- 9% vs 5.7 +/- 9%, p = 0.01). CONCLUSIONS Mild symptoms of heart failure and independent predictors of left ventricle function recovery after PCI in patients with impaired LVEF. The lack of angina symptoms negatively influence LVEF recovery after PCI.