ABSTRACT: INTRODUCTION:Periprocedural bleeding related to coronary angiography (CAG) or percutaneous coronary intervention (PCI) is associated with worse prognosis. Determining genetic variations associated with increased bleeding risk may help to identify high-risk patients. AIM:To analyse the association between single nucleotide polymorphisms (SNPs) of crucial haemostatic platelet receptors (GPIa, GPVI, P2Y12) and the risk of periprocedural bleeding complications related to CAG/PCI. MATERIAL AND METHODS:The population consisted of 73 patients with ischaemic heart disease who developed bleeding complications within 30 days after CAG/PCI and 331 patients without bleeding. The frequency of SNPs of GPIa 807C/T, GPVI 13254T/C, P2Y12 32C/T, and P2Y12 H1/H2 haplotype was analysed using polymerase chain reaction (PCR) hybridization methods. RESULTS:The prevalence of variant alleles GPIa 807T, GPVI 13254C, P2Y12 34T, and P2Y12 H2 haplotype in the total study population was 56.7%, 20.3%, 56.2%, and 24.3%, respectively. The presence of variant alleles was not related to increased risk of periprocedural bleeding: GPIa 807C/T (OR = 1.29, 95% CI: 0.75-2.24, p = 0.334), GPVI 12354T/C (OR = 0.82, 95% CI: 0.40-1.64, p = 0.551), P2Y12 34C/T (OR = 0.71, 95% CI: 0.42-1.22, p = 0.189), P2Y12 H1/H2 haplotype (OR = 0.69, 95% CI: 0.35-1.36, p = 0.258). The frequency of the homozygous form of P2Y12 H2 haplotype was higher in the group of patients who developed bleeding (OR = 2.79, 95% CI: 0.51-13.77, p = 0.161). CONCLUSIONS:No significant association of the SNPs of GPIa 807C/T, GPVI 13254T/C, P2Y12 32C/T, and P2Y12 H1/H2 haplotype with increased risk of periprocedural bleeding was found in patients with ischaemic heart disease undergoing CAG/PCI.