Fibrinogen concentrate to cardiac surgery patients with ongoing bleeding does not increase the risk of thromboembolic complications or death.

In this retrospective, observational study, Waldén et al. describe the occurrence of thromboembolic events and mortality in cardiac surgery patients, depending on whether the patient had received fibrinogen supplementation. The study comprises 5,408 patients, of which 564 (10.4%) received fibrinogen during cardiac surgery.

Patients receiving fibrinogen had lower preoperative levels of fibrinogen and platelet count, longer prothrombin times and a higher EuroSCORE I, as well as a longer bypass time. They bled more excessively and required higher transfusion volumes of blood products. The primary composite outcome was: frequency of thromboembolic events and mortality within one year.

In the unadjusted analysis, the occurrence of the primary endpoint was 15.1% in fibrinogen-treated patients versus 9.9% in the remaining patients (HR: 1.56, 95% CI: 1.24-1.97, P < 0.001). After adjusting for age, sex, BMI, preoperative antiplatelet therapy, plasma fibrinogen concentration, haemoglobin, platelet count, preoperative creatinine, prothrombin time, previous stroke, valve surgery, Euroscore, bypass time, and perioperative transfusion need, there was no significant difference in the occurrence of the primary outcome between patients treated with or without fibrinogen (HR: 1.11, 95% CI: 0.84-1.46, P = 0.45). There was no difference either in secondary outcomes, including mortality at 1-year, composite outcome at 30 days and mortality at 30 days. Propensity score matched analysis was performed as sensitivity analyses, confirming observations from the main analyses.

The strength of this study is the information derived from detailed clinical data combined with an almost complete follow-up based on national registry data of high validity.

– Hanne Berg Ravn