The role of different mechanical circulatory support devices and their timing of implantation on myocardial damage and mid-term recovery in acute myocardial infarction related cardiogenic shock

Objectives: Aim of the study was to assess in-hospital survival rate and the degree of myocardial recovery after MCS treatment (IABP or IMPELLA) at discharge and at 6 months in patients with AMI-CS and planned early percutaneous revascularization. Background: All studies on MCS for acute myocardial infarction related cardiogenic shock (AMI-CS) focused on its impact on in-hospital mortality; however, few data about its role on myocardial recovery are available. Methods: Retrospective study on 64 patients: 36 patients (56%) received IABP and 28 (44%) Impella 2.5/CP. Results: Patients treated with Impella were sicker compared to those treated with IABP as shown by a higher need of catecholamines (93% Impella vs 57% IABP, P = 0.002) and higher inotropic score before procedure: 8 (5-15) versus 4.5 (0-9), P = 0.02. In-hospital survival and MCS-related complications were comparable; hemolysis was more frequent in the Impella group (32% vs 0%, P < 0.0001). Myocardial damage was lower in those patients who were implanted with IMPELLA before PCI: lower troponin peak [3831 ng/dL (1441-8436) vs 16 581 (7802-23 675), P = 0.004] and lower CPK peak [893 UI/L (584-4082) vs 5797 (2483-9292) P = 0.04]. Impella patients had higher LVEF at 6 months [45 (38-52) vs 40 (33-45)%, P = 0.04]. LVEF increase at 6 months was statistically significant in both groups (P < 0.0001), with higher myocardial recovery in patients supported with Impella (absolute delta-LVEF increase 20% vs 10% P = 0.005). Conclusions: Cardiac unloading with IMPELLA in ACS-CS, especially if implanted before PCI, might provide lower myocardial damage and improved myocardial recovery which translates into significantly higher LVEF at 6 months.