CLINICAL AND ANGIOGRAPHIC CHARACTERISTICS OF PATIENTS WITH STENT THROMBOSIS

Stent thrombosis (TS) after percutaneous coronary intervention (PCI) is a rare but potentially fatal complication with an incidence of 1% to over 5%. Risk factors for TS can be divided into factors related to the patient, procedure, stent type and characteristics of the lesion. One thousand fifty-five patients who underwent PCI during 2009 and 2010 were included into the study and followed during the next year. Patients with and without definite TS formed the study (TS+) and control group (TS+), respectively. Twenty-three patients had TS (2,2%). Early, late and very late TS were noted in 69,5%, 13,1% and 17,4% of patients, respectively. Acute myocardial infarction with STsegment elevation was the most frequent clinical presentation (56,6%). Discontinuation of aspirin and/or clopidogrel (34.8%) and resistance to these drugs (34.7%) were the main patient-related factors for TS. A higher percentage of stenosis of lesions (92 ± 12 vs 86 ± 14), greater average stent length (19.69 vs 17.01 mm), lower pressure stent insufflation (14.84 vs. 16.02 atm) and coronary artery dissection (26.1%) were significant reasons for the occurrence of TS. Similar stent type BMS („bare metal stents) and DES („drug eluting stents“) were applied in both of patient groups. STEMI patients and those with impaired systolic left ventricular function are at highest risk of TS, which is reported in more than two thirds of them in the first 30 days after PCI. Discontinuation of aspirin and/or clopidogral or resistance to these drugs led to TS. Greater stent length, small diameter of the stent ("underestimated lesion"), lower pressure insufflation and dissection of the coronary artery are the most common procedural reasons for the occurrence of TS. Type of stent (BMS and DES) had no significant effect on the occurrence of TS. Acta Medica Medianae 2013;52(4):5-11.