['The objective of this study was to evaluate the impact of contrast medium volume, inferior mesenteric artery (IMA) patency, and pre-existing as well as new-onset thrombus on the inflammatory response after elective endovascular aneurysm repair (EVAR).', 'The study included 87 patients undergoing elective endovascular repair of asymptomatic infrarenal aneurysms between January 2011 and November 2011. The patency of the IMA was determined by preoperative computed tomography angiography; the volume of the contrast medium used during the procedure was measured, and the volumes of chronic mural as well as new-onset thrombus were calculated from the preoperative and postoperative computed tomography angiograms with dedicated imaging software. The results were correlated to the occurrence of postimplantation syndrome (PIS) as well as to the main clinical and laboratory components of PIS: fever; increased white blood cell (WBC) count and C-reactive protein (CRP) level; decreased platelet count; and increased interleukin (IL)-6, IL-8, and IL-10 levels.', 'Postoperatively, a statistically significant increase was recorded in the mean values of body temperature, WBCs, CRP, IL-6, IL-8, and IL-10, and a statistically significant decrease was recorded in the number of platelets. After adjustment for endograft type, the volume of new-onset thrombus was found to be significantly correlated with the peak postoperative temperature (β\xa0= .307; P\xa0< .05) and the increase in WBC count (β\xa0= .271; P\xa0< .05), CRP level (β\xa0= .484; P\xa0<\xa0.001), and IL-6 level (β\xa0= .288; P\xa0< .05). On the contrary, the volume of chronic mural thrombus, the patency of the IMA, and the volume of contrast medium were not found to significantly affect any parameter of the PIS. PIS occurred in 34 patients (39%). Multiple logistic regression analysis showed that both the volume of new-onset thrombus and the type of endograft were independently associated with the development of PIS.'] Is volume of new-onset thrombus associated with the development of postimplantation syndrome after endovascular aneurysm repair?