Impact of the Timing of Mechanical Circulatory Support on the Outcomes in Myocardial Infarction-Related Cardiogenic Shock: Subanalysis of the PREPARE CS Registry.

(1) Background : Mechanical circulatory support (MCS) in myocardial infarction-associated cardiogenic shock is subject to debate. This analysis aims to elucidate the impact of MCS's timing on patient outcomes, based on data from the PREPARE CS registry. (2) Methods : The PREPARE CS prospective registry includes patients who experienced cardiogenic shock (SCAI classes C-E) and were subsequently referred for cardiac catheterization. Our present analysis included a subset of this registry, in whom MCS was used and who underwent coronary intervention due to myocardial infarction. Patients were categorized into an Upfront group and a Procedural group, depending on the timing of MCS's introduction in relation to their PCI. The endpoint was in-hospital mortality. (3) Results : In total, 71 patients were included. MCS was begun prior to PCI in 33 (46%) patients (Upfront), whereas 38 (54%) received MCS during or after the initiation of PCI (Procedural). The groups' baseline characteristics and hemodynamic parameters were comparable. The Upfront group had a higher utilization of the Impella® device compared to extracorporeal membrane oxygenation (67% vs. 33%), while the Procedural group exhibited a balanced use of both (50% vs. 50%). Most patients suffered from multi-vessel disease in both groups (82% vs. 84%, respectively; p = 0.99), and most patients required a complex PCI procedure; the latter was more prevalent in the Upfront group (94% vs. 71%, respectively; p = 0.02). Their rates of complete revascularization were comparable (52% vs. 34%, respectively; p = 0.16). Procedural CPR was significantly more frequent in the Procedural group (45% vs. 79%, p < 0.05); however, in-hospital mortality was similar (61% vs. 79%, respectively; p = 0.12). (4) Conclusions : The upfront implantation of MCS in myocardial infarction-associated CS did not provide an in-hospital survival benefit.