Usefulness of Impella support in different clinical settings in cardiogenic shock

BACKGROUNDThe Impella pump has emerged as a promising tool in patients with cardiogenic shock (CS). Despite its attractive properties, there are scarce data on the specific clinical setting and the potential role of Impella devices in CS patients from routine clinical practice.METHODSThis is an observational, retrospective, single center, cohort study. All consecutive patients with diagnosis of CS and undergoing support with Impella 2.5^®, Impella CP^® or Impella 5.0^® from April 2015 to December 2020 were included. Baseline characteristics, management and outcomes were assessed according to CS severity, age and cause of CS. Main outcome measured was in-hospital mortality. RESULTSA total of 50 patients were included (median age: 59.3 ± 10 years). The most common cause of CS was acute coronary syndrome (ACS) (68%), followed by decompensation of previous cardiomyopathy (22%). A total of 13 patients (26%) had profound CS. Most patients (54%) improved pulmonary congestion at 48 h after Impella support. A total of 19 patients (38%) presented significant bleeding. In-hospital mortality was 42%. Among patients with profound CS (n = 13), five patients were previously supported with venoarterial extracorporeal membrane oxygenation. A total of eight patients (61.5%) died during the admission, and no patient achieved ventricular recovery. Older patients (≥ 67 years, n = 10) had more comorbidities and the highest mortality (70%). Among patients with ACS (n = 34), 35.3% of patients had profound CS; and in most cases (52.9%), Impella support was performed as a bridge to recovery. In contrast, only one patient from the decompensated cardiomyopathy group (n = 11) presented with profound CS. In 90.9% of these cases, Impella support was used as a bridge to cardiac transplantation. There were no cases of death. CONCLUSIONSIn this cohort of real-life CS patients, Impella devices were used in different settings, with different clinical profiles and management. Despite a significant rate of complications, mortality was acceptable and lower than those observed in other series.

Cardiogenic shock (CS) is a severe clinical condition which includes systemic hypotension and tissue hypoperfusion secondary to cardiac dysfunction with adequate or elevated filling pressures, and is commonly associated to a poor prognosis.^1] Clinical practice guidelines^2] recommend the use of inotropic drugs and vasopressors in order to maintain organ perfusion, early revascularization in cases due to acute coronary syndrome (ACS) and the use of mechanical circulatory support (MCS) in refractory cases.^1,2] However, despite all these measures, mortality remains high in most series.^3] The use of inotropic drugs and vasopressors increases myocardial oxygen consumption and proarrhythmic risk,^4] and the use of MCS is associated with a high rate of complications^5]. A better prognosis has been consistently observed in high volume centers with full availability of percutaneous coronary intervention (PCI), MCS, intensive cardiac care unit and especifically trained shock teams.^6–10] Given the complexity of these patients, current guidelines recommend to organize the care of CS in different center networks according to the severity of patients.^2]As stated before, MCS has emerged during the last years as a promising tool in critically ill patients with refractory CS. The ideal device in patients with CS requires an easy and quick insertion, the ability to unload left ventricle (LV) and increase cardiac output in order to restore tissue hypoperfusion. In this sense, the Impella devices (Abiomed Inc., Massachusetts, USA), consists of a transvalvular axial pump with femoral or axillary insertion that collects blood from the LV and ejects it directly into the ascending aorta.^3] The Impella device provides MCS with an increase in mean arterial pressure, an increase in cardiac output and peak coronary blood flow while unloading LV, reducing end-diastolic volume, wall stress and oxygen consumption, thus favoring myocardial recovery.^1,3] However, despite these attractive properties, there are scarce data on the specific clinical setting to use Impella devices and the efficacy and complications in its use in real world. Most publications report experience in high risk PCI or after acute myocardial infarction complicated by CS.^11]Therefore, the aim of this study was to collect the results and complications of the use of Impella devices in a real world high complexity CS referral center over a five-year period in non-selected patients with CS of any etiology.