Summary: In a prespecified subgroup analysis of the BRIGHT-4 trial, bivalirudin with a prolonged post-procedure infusion reduced death or major bleeding versus heparin in heart-attack patients with lower BMI, but gave no benefit in those with higher BMI, with a significant interaction by BMI.
PICO Summary
| Element | Detail |
|---|---|
| Population | 6,016 STEMI patients undergoing primary PCI, mostly via radial access, stratified by BMI (<25 vs ≥25 kg/m²); prespecified subgroup of the BRIGHT-4 RCT, China. |
| Intervention | Bivalirudin with a high-dose infusion for 2–4 hours after PCI. |
| Comparison | Heparin monotherapy during PCI without post-procedural infusion. |
| Outcome | In BMI <25, bivalirudin reduced 30-day death or BARC 3–5 bleeding (3.2% vs 5.7%; adjusted HR 0.56, 95% CI 0.40–0.79). In BMI ≥25, there was no difference (2.9% vs 2.9%; adjusted HR 0.97, 95% CI 0.62–1.52). The interaction by BMI was significant (p=0.04), driven mainly by bleeding. |
Bivalirudin vs heparin in STEMI, by BMI
RCT subgroup · STEMI primary PCI · 30 days
Bivalirudin with a post-procedure infusion cut death or major bleeding versus heparin in lower-BMI STEMI patients but not higher-BMI patients, with a significant BMI-by-treatment interaction driven by bleeding.
Expert Commentary
This is a well-conducted subgroup analysis of a major anticoagulation trial, and its interest for a metabolic audience is the BMI-by-treatment interaction, which was prespecified and statistically significant rather than a chance finding dredged after the fact. The clinical story is coherent: the bivalirudin advantage concentrated in lower-BMI patients and was driven by reduced major bleeding, consistent with the idea that thinner patients carry higher bleeding risk where a bleeding-sparing strategy pays off most, while heavier patients saw neither benefit nor harm. The honest caveat is the one the authors themselves raise, that subgroup results, even prespecified ones, warrant caution, the BMI cut-point of 25 is conventional rather than biologically optimal, and the predominantly Asian population with very high radial-access rates may not generalise to other settings or to femoral access. Can I use this with my patients? At the margins of decision-making rather than as a rule. For a lower-BMI STEMI patient at elevated bleeding risk, this nudges me toward favouring bivalirudin with the post-procedure infusion, while treating either agent as reasonable in higher-BMI patients and remembering this is hypothesis-refining subgroup evidence.
References
Zhang D, Li Y, Qiu M, et al. BMI differences on anticoagulation with bivalirudin vs. heparin during primary PCI: a BRIGHT-4 subanalysis. BMC Med. 2025;23(1):525. doi:10.1186/s12916-025-04374-7