Relationship between hypercoagulability and mesenteric ischemia early after cardiac surgery.

Cardiac surgery is considered to be a hypercoagulable state with an increased incidence of thromboembolic events. To evaluate the connection between hypercoagulability and mesenteric ischemia (Me-Is), we investigated hemostatic parameters in patients with diagnosed Me-Is. Out of a cohort of 500 consecutive cardiac surgery patients, 25 patients with hyperinflammatory indicators (interleukin-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, on intensive care unit (ICU) admission, and 12 h after ICU admission were assessed for hemostatic parameters, including fibrinogen, D-dimer, thrombin-anti-thrombin complex (TAT), and prothrombin fragments 1 + 2 (F1.2). Thrombin generation assays were conducted on all samples, and intestinal fatty acid-binding protein (I-FABP) was assessed as a marker for Me-Is. Baseline levels of hemostatic markers were similar between the two groups. TAT levels were significantly higher in the Me-Is group 12 h after ICU admission (54.20 ± 10.49 vs. 22.18 ± 12.43 ng/ml, p = 0.010). In contrast, at ICU admission, absolute F1.2 values were higher in the control group (1.19 ± 0.04 vs. 0.49 ± 0.47 ng/ml, p = 0.047). However, increase of F1.2 values of the Me-Is group (394.2 ± 231.6%) vs. the control group (114.7 ± 144.9%) 12 h after ICU admission were 3.9- vs. 1.1-fold compared to baseline (p = 0.046). Postoperatively, higher levels of I-FABP and of D-dimers were observed in the Me-Is group 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 h 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) compared to the control group. No significant differences were observed for parameters of thrombin generation (TGA, peak value, ETP) between the two groups. Our findings suggest that TAT and F1.2 levels are promising candidates as markers of coagulability after cardiac surgery. High levels of activation markers suggest a temporary stage of hypercoagulability immediately after surgery in Me-Is patients. Nevertheless, the serial assessment of thrombotic profiles offers valuable mechanistic insights, although these exploratory findings require confirmation in larger cohorts.