Effect of HA380 hemoperfusion on cardiac valve surgery and systemic inflammation at high altitude

Objective To evaluate the clinical efficacy of HA380 hemoperfusion (HP) for systemic inflammatory response syndrome (SIRS) in adult patients undergoing cardiac valve surgery at high and low altitudes. Methods A total of 120 patients undergoing valve replacement under cardiopulmonary bypass (CPB) were prospectively enrolled from high-altitude (2800-3200m, n=60) and low-altitude (100-200m, n=60) centers. Within each center, patients were randomized (1:1) to receive either conventional CPB (H-CPB, L-CPB) or CPB combined with HA380 HP (H-HF, L-HF), creating four study groups (n=30 per group). Inflammatory markers, including WBC, PCT, hs-CRP, and IL-6, were measured at multiple time points: preoperatively (T0), at CPB weaning (T1), 2 hours postoperatively (T2), 24 hours postoperatively (T3), and 48 hours postoperatively (T4). Our pre-specified primary endpoint was the change in white blood cell (WBC) count at T1. Secondary endpoints included procalcitonin (PCT), other inflammatory markers, and specific clinical outcomes. This randomized trial is reported in accordance with the CONSORT 2010 statement. The study was retrospectively registered at the China Clinical Trial Registration Center (Registration Number: MR-63-26-032364) after the first patient enrollment in May 2023, acknowledging the potential risk of bias associated with retrospective registration. Results Operative time and hospital stay were significantly shorter in the hemoperfusion groups (H-HF, L-HF) compared to their respective conventional CPB groups (H-CPB, L-CPB) (p<0.01). After adjustment for baseline WBC counts, center effects, and multiple testing, HA380 hemoperfusion resulted in a 10% reduction in WBC at T1 in the high-altitude stratum compared with conventional CPB (adjusted mean difference -0.8 × 10⁹/L; 95% CI -1.5 to -0.1; p = 0.03), and a similar 10% reduction at low altitude (-0.7 × 10⁹/L; 95% CI -1.4 to 0.0; p = 0.048). PCT and hs-CRP levels were lower at T0 and at early postoperative time points (T1–T2) in the hemoperfusion groups; however, at later time points (T3–T4), these markers were higher in HA380-treated patients, particularly in the high-altitude stratum. These findings should be interpreted as exploratory and time-dependent, potentially reflecting physiological rebound or selective adsorption effects, rather than a sustained clinical benefit. Importantly, no significant differences were observed between groups for most clinical endpoints beyond operative time and hospital stay . No significant differences were found in IL-6 and lactate levels, reinforcing the limited impact of HA380 hemoperfusion on these particular inflammatory markers, particularly given the small proportion of total CPB flow that passes through the filter. Conclusion HA380 hemoperfusion during CPB may attenuate inflammatory responses and improve clinical outcomes (reduced operative time, shorter hospital stay) in valve replacement patients at both high and low altitudes, with more prominent effects on early inflammatory markers.