Aim. To assess frequency of unstable angina due to restenosis after percutaneous angioplasty of venous grafts and to elucidate risk factors of its development. Material and methods. Percutaneous interventions were successfully performed in 100 out of 106 patients with venous graft stenoses. These patients were followed up for 17+/-11 (maximum 36) months. Results. Unstable angina due to venous graft restenosis developed in 24% of patients. Patients with unstable angina compared with those without were characterized by higher frequency of hyperlipidemia (83 vs. 51%, respectively, p=0.032), lower rate of stenting (46 and 72%, respectively, p=0.032), greater residual stenosis (15+/-13 and 9+/-8%, respectively, p=0.008). At multifactorial regression analysis the following factors were significant predictors of unstable angina: hyperlipidemia (odds ratio [OR] 3.55, 95% confidence interval [CI] 1.64-8.39), and residual stenosis after intervention (OR 1.04, 95% CI 1.01-1.07, p=0.04). In a subgroup of patients with hyperlipidemia there was a tendency to greater rate of unstable angina among patients not taking statins compared with users of statin (50 and 29%, respectively, p=0.083). Conclusion. Unstable angina developed in 1/4 of patients after balloon dilatation of venous grafts and hyperlipidemia was its most powerful predictor.