Abstract 4367421: Cardiogenic Shock Patients Achieving Native Heart Survival With Impella 5.5 Support Still Experience Significant Skeletal Muscle Loss

Background: Impella 5.5 is increasingly used to support patients with cardiogenic shock, some of whom recover native heart function without requiring durable mechanical support or transplant. The degree of catabolic stress in this population remains poorly characterized. We evaluated changes in skeletal muscle mass, using psoas muscle index (PMI), in patients with native heart survival following Impella support. Methods: We retrospectively analyzed 26 patients with cardiogenic shock treated with Impella 5.5 who recovered native cardiac function. PMI was calculated from CT scans obtained pre-implant and post-explant. Patients were stratified by initial SCAI shock stage. Paired t-tests, Mann-Whitney U tests, and Spearman correlations were used for statistical analysis. Results: Across the cohort, PMI significantly declined during support (mean ΔPMI: –0.25, p = 0.0091). Patients presenting with SCAI Stage A experienced greater PMI loss (median ΔPMI: –0.51) than those with SCAI Stages B–E (median ΔPMI: –0.18), though this difference did not reach statistical significance ( p = 0.097) (Figure). Pre-implant PMI was numerically higher in SCAI A patients, but not statistically different ( p = 0.27). No correlation was observed between PMI loss and post-explant hospitalization duration (ρ = 0.044, p = 0.83). Conclusion: Patients with Impella-supported cardiogenic shock who recover native heart function still experience significant skeletal muscle loss. A trend toward greater loss in SCAI A patients may reflect longer duration of support, higher baseline muscle mass, or survivorship bias. These findings are hypothesis-generating and suggest a potential role for early rehabilitation or nutritional interventions during support.