Does a Postimplantation Syndrome Following Endovascular Treatment of Aortic Aneurysms Exist?

Abstract

The postimplantation syndrome (PIS) is a weakly defined condition that has been observed following endovascular treatment of aortic aneurysms; the postulated criteria include significant leukocytosis, fever, and/or coagulation disturbances. Among the factors that are supposed to contribute to this syndrome are contact activation by the stent covering with consecutive endothelial activation. Associated clinical parameters of a PIS were perioperatively monitored in the postoperative phase in a total of 69 patients with infrarenal aortic aneurysms treated with Y-stent grafts. C-reactive protein (CRP)-levels, leukocyte concentrations, and body temperature curves were directly compared to those of 50 patients undergoing conventional transperitoneal aneurysm resection. A subgroup of 10 patients of the endovascular group was compared with 13 operated-on patients with regard to an ischemia-reperfusion syndrome of the lower extremities. The mediator determinations were performed on venous (femoral vein) as well as in systemic (arterial) blood samples. The incidence of temperature values above 38 degrees C was higher in patients following endovascular treatment (72%) compared to conventionally operated-on patients (28%). CRP levels were not significantly different within the first 8 post-operative days. During open surgery, significantly higher values for lactate and lower pH levels were observed (p<0.01), as well as higher 6 keto prostaglandin F1alpha (PGF1alpha) levels. There was a short peak of PGF1alpha during eventeration of the intestine during the operative procedure that could not be detected during endovascular manipulations. The clinical and biochemical parameters do not prove the presence of a PIS following endovascular treatment of aortic aneurysms. In contrast, during open surgery the unspecific inflammatory reaction is higher, but not long-lasting. In the future, the suggested phenomenon of a decreased antiinflammatory cytokine response during endovascular surgery needs to be further examined.