Tranexamic acid ups blood control after CABG, but aggravates perioperative myocardial infarction

While tranexamic acid (TXA) improves blood control after coronary artery bypass graft (CABG) surgery, it increases the risk of perioperative myocardial infarction (PMI), a recent study has found.

The retrospective study included 42,010 patients who had undergone CABG. Most were given TXA (n=29,536) while 12,474 were not. The TXA group was further subdivided into the high-dose (≥50 mg/kg; n=16,488) and low-dose (<50 mg/kg; n=13,048) subgroups. The primary endpoint was a composite of hospital death, PMI, stroke, acute kidney injury (AKI), and pulmonary embolism, assessed after propensity score matching. Secondary endpoints included blood loss and blood transfusion.

Conditional logistic regression analysis found that in the matched cohort, TXA increased the risk of the primary endpoint by nearly 20 percent (odds ratio [OR] 1.18, 95 percent confidence interval [CI] 1.08–1.29; p<0.001).

Such an effect was driven by the elevated likelihood of PMI (OR, 1.37, 95 percent CI, 1.21–1.56; p<0.001) and stroke (OR, 1.283, 95 percent CI, 0.996–1.654; p=0.054). No significant impact was detected for death (p=0.478), AKI (p=0.207), and pulmonary embolism (p=0.793).

Despite being at greater risk of the above complications, the TXA patients were significantly less likely to need reoperation for bleeding or tamponade (p<0.001). Similarly, total blood loss and blood loss 24 and 48 hours after surgery were all significantly lower in the TXA group (p<0.001 for all). Notably, high-dose TXA led to a stronger reduction in blood loss but did not affect the risk of reoperation.