Abstract 3548: Human Plasma Proteome and Hemodynamic Changes After Aortic Aneurysm Repair
Abdominal Aortic Aneurysm (AAA) repair, often results in the release of proinflammatory cytokines and may be followed by cardiovascular complications. However, whether a relationship exists between the systemic inflammatory response and the occurrence of cryptic hemodynamic alterations in uncomplicated procedures is still unknown. Therefore we investigated the time course of plasma proteins involved in ischemia-reperfusion injury using two-dimensional difference gel electrophoresis. Hemodynamic changes were continuously monitored using a system based upon online, real-time, digital processing of intraarterial radial pressure waveform analysis. Ten patients (aged 68±6 years) undergoing infrarenal AAA repair. Eight age and sex matched subjects undergoing major abdominal surgery (AS) served as controls. We compared plasma samples obtained after induction of anesthesia with those obtained at different times after surgery (30 min and 6h, 12h, 24h, 36h). At the same times, plasma interleukin-6 (IL-6) was also assayed. In AAA patients we detected 30 spots which changed more than two-fold in expression level and 16 spots were identified. Among these, thrombin generation increased 6h after surgery with a contemporary reduction in complement factor B and decreased to normal expression level at 12h, when plasma IL-6 concentrations were significantly increased. Haptoglobin, α-2-HS glycoprotein, α-2 antichimotrypsin, cerulo-plasmin, α-2 antiplasmin were all increased between 12h and 36h after surgery with a contemporary shift towards a higher isoelectric point. No patient had cardiovascular complications. In AAA patients, a significant increase in systolic blood pressure and instantaneous arterial dP/dT was detectable at 6h after reperfusion vs values measured at the end of surgery (from 1.06±0.1 to 1.41±0.06 mmHg/s, p<0.05). At 12h dP/dT was reduced vs peak value (0.99±0.11 mmHg/s, p<0.05). The capability of plasma to inhibit myocardial contractility was confirmed by testing plasma samples obtained at the same time-frames on isolated rat ventricular myocytes in vitro. These findings show for the first time the relationship between the activation of inflammatory response and cryptic hemodynamic changes following infrarenal AAA repair.