Advanced Heart Failure and Transplant Cardiologist, United States
Background: Temporary mechanical circulatory support (t-MCS) is increasingly utilized for cardiogenic shock (CS) refractory to pharmacologic therapy. Impella 5.5 devices offer prolonged circulatory support and can facilitate native heart survival or transition to durable therapies. However, optimal patient selection, timing of implantation, and clinical predictors of stabilization remain unclear.
Methods: The purpose of the study is, 1) compare the clinical characteristics of patients who stabilize versus those who deteriorate after receiving Impella 5.5 support; (2) evaluate in-hospital outcomes and adverse event profiles based on stabilization status; and (3) identify factors associated with stabilization versus deterioration following Impella 5.5 therapy.
We analyzed data from the Cardiogenic Shock Working Group (CSWG) registry, including 937 patients with CS who received Impella 5.5 between 2020 and 2024. Stabilization was defined as successful weaning from Impella 5.5 or bridging to durable heart replacement therapy (HT or LVAD) without escalation to additional t-MCS. Multivariate logistic regression identified clinical and hemodynamic predictors of stabilization.
Outcome: Of 937 patients, 649 (69%) achieved stabilization. HF-CS patients had higher stabilization rates compared to MI-CS (72.3% vs. 61.4%; p=0.007). Upfront Impella 5.5 implantation was more common among patients who achieved stabilization compared with those who deteriorated (53% vs. 36%; p< 0.0001). In multivariable analysis, older age, severe valvular disease, prior CABG, and prior Impella CP or ECMO support were independently associated with lower odds of stabilization, whereas higher mean arterial pressure was independently associated with stabilization. Among stabilized patients, 34.2% achieved native heart survival, while 65.8% underwent heart replacement therapy; among these, 38.7% had HT and 27.1% had LVAD (p < 0.001).
Conclusion: Impella 5.5 therapy facilitated clinical stabilization in most CS patients, particularly those with HF-CS, and served as an effective bridge to HT or LVAD. Prospective studies are needed to validate standardized escalation protocols and optimize CS management.
