Immunoadsorption and subsequent immunoglobulin G replacement (IA/IG) in patients with dilated cardiomyopathy: a systematic review and meta-analysis

Background Dilated cardiomyopathy (DCM) is a refractory cardiac disease with significant morbidity and mortality. Although immune adsorption combined with immunoglobulin G replacement therapy (IA/IG) has shown potential in treating DCM, only small-scale clinical trials have been reported. Its efficacy and safety characteristics still need to be further systematically evaluated. Methods We conducted a systematic review and meta-analysis in accordance with PRISMA 2020 guidelines. A comprehensive search of PubMed, Embase, Web of Science, and the Cochrane Library was performed up to July 1, 2025. Clinical studies on IA/IG treatment for DCM were included. The primary outcome was the left ventricular ejection fraction (LVEF) change. Secondary outcomes included left ventricular end-diastolic dimension (LVEDD), NYHA functional class, N-terminal pro-brain natriuretic peptide (NT-proBNP), and VO2 peak. Study quality and risk of bias were assessed using the Cochrane ROB 2.0 and ROBINS-I tools. Sensitivity analysis was taken into consideration to determine the stability of the results. This review was registered with PROSPERO (CRD420251104796). Results Eighteen studies (2 RCTs and 16 non-RCTs) involving 809 participants were included. IA/IG therapy significantly improved LVEF [mean difference (MD) = 7.71%, 95% CI: 6.18–9.24, p < 0.00001] and reduced LVEDD (MD = −3.22 mm, 95% CI: −4.16 to −2.28, p < 0.00001) from baseline. Significant improvements were also observed in NYHA functional class (MD = −0.76, 95% CI: −0.91 to −0.60, p < 0.00001) and peak VO₂ (MD = 2.66 mL/kg/min, 95% CI: 1.26–4.06, p = 0.0002). Compared to controls, the IA/IG group demonstrated greater improvement in LVEF (MD = 8.31%, 95% CI: 6.45–10.18, p < 0.00001) and NYHA class (MD = –0.62, 95% CI: −1.00 to −0.25, p = 0.001). A sensitivity analysis of the results suggested that they were stable. Conclusion Systematic reviews and meta-analyses suggest that IA/IG therapy may improve cardiac function and quality of life in patients with DCM. However, the number of RCTs included in the study is limited, so these results should be interpreted with caution. Further high-quality, large-scale trials are warranted to establish standardized treatment protocols and confirm the long-term benefits of IA/IG therapy. Systematic Review Registration https://www.crd.york.ac.uk/PROSPERO/recorddashboard , PROSPERO CRD420251104796.