Relationship between Hypercoagulability and Mesenteric Ischemia early after Cardiac Surgery

Abstract

Background: Cardiac surgery is considered to be a hypercoagulable state with an increased incidence of thromboembolic events. In acute mesenteric ischemia (Me-Is), plasma coagulation markers may have additional diagnostic relevance perioperatively. Methods: Out of 500 consecutive cardiac surgery patients, 25 patients with hyperinflammatory (IL-6 >600 ng/l) and metabolic acidosis (lactate >4 mmol/l) were retrospectively matched 1:4 into Me-Is (n=5) and control (n=20) groups. Blood samples collected before surgery, upon ICU admission and 12 hours after ICU admission were assessed for hemostatic parameters, including fibrinogen, D-dimer, thrombin-anti-thrombin complex (TAT), prothrombin fragments 1+2 (F1+2). All samples were also evaluated in thrombin generation assays, and intestinal fatty-acid-binding protein (I-FABP) was assessed as a marker for Me-Is. Results: Baseline levels of hemostatic markers in the two groups were similar. TAT levels were significantly increased in the Me-IS group at 12h after ICU admission, respectively (54.20 ±10.49 vs 22.18±12.43 ng/ml, p=0.010). In contrast, at ICU admission, absolute F1+2 values were significantly increased in the control group (1.19±0.04 vs. 0.49 ± 0.47 ng/ml, p=0.047). However, the relative F1+2 values of the Me-Is group (394.2±231.6%) vs. the control group (114.7±144.9%) within 12 hours after ICU admission were 3.9- vs. 1.1-fold higher than baseline (p=0.040). Postoperatively, significantly higher levels of I-FABP and of D-dimers were observed in the Me-Is group vs. controls at ICU admission, (17116.2±18185.4 vs. 2252.3±1582.7 pg/ml [p=0.006] and 5.3±1.3 vs. 3.0±2.1 μg/ml [p=0.043], respectively) and 12 hours after ICU admission (16998.2±20346.3 vs. 1030.8±1100.0 pg/ml [p=0.030] and 3.7±1.8 vs. 1.2±0.8 μg/ml [p=0.005], respectively). No significant differences were observed for thrombin generation (TGA, peak value, ETP) between the two groups. Conclusion: Our findings suggest that TAT and F1+2 levels are promising candidate markers for evaluating coagulability after cardiac surgery. High levels of activation markers suggest a temporary stage of hypercoagulability immediately after surgery in Me-Is patients.