Clinical outcomes of Impella support for cardiogenic shock and high-risk percutaneous coronary intervention
Authors: Brandao M , Santos Silva G , Ribeiro Silva M , Ribeiro Queiros P , Goncalves Teixeira P , Goncalves Almeida J , Pires-Morais G , Oliveira M , Rodrigues A , Braga P , Caeiro D , Fontes-Carvalho R 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The Impella is a percutaneous ventricular assist device that unloads the left ventricle by ejecting blood to the aorta. Its use in cases of cardiogenic shock (CS) and high-risk percutaneous coronary intervention (HR-PCI) is increasing.

Purpose
To report clinical outcomes with the Impella device in the settings of CS and HR-PCI.

Methods
Single-center retrospective study including consecutive patients (2007-2019) implanted with Impella for CS treatment or hemodynamic support of HR-PCI.

Results
22 patients were included: 12 were treated for CS and 10 underwent Impella-supported PCI. Impella 2.5 (7) and Impella CP (15) were used.
In the CS group (75.9% male, mean age 50.4 ± 18.9, median duration of support 19 ± 24 hours), CS etiologies were myocardial infarction (41.7%), acute myocarditis (25.0%) and acute decompensated heart failure (33.3%). All patients presented with multiorgan dysfunction and were in stage D or E of the SCAI classification of CS. Most patients (83.3%) had severe left ventricular (LV) dysfunction and half also had right ventricular impairment. In 5 cases, combined support of Impella and venoarterial extracorporeal membrane oxygenation (ECMO) was used: in 2 patients, Impella was implanted for LV venting; 3 patients needed escalation to ECMO due to refractory CS. Hemolysis was the most frequent device-related complication (63.7%). Three patients had BARC type 3 vascular complications. Three patients were transferred to a transplantation center, but none survived to transplant. In-hospital, cumulative 30-day and 1-year mortality were 58.3%, 66.6% and 83.3%, respectively.
In the HR-PCI group (all male, mean age 73.7 ± 9.1 years, 50% diabetic, mean left ventricular ejection fraction 39.4 ± 13.6) all patients had multivessel, highly complex, coronary disease (mean baseline SYNTAX I score 44.1 ± 13.7); six had a last remaining conduit. All patients were considered ineligible for surgery by the Heart Team. Half of the patients underwent PCI in the setting of an acute coronary syndrome. Median number of vessels treated was 2 ± 1. Seven patients underwent unprotected left main PCI. Impella was immediately explanted after PCI in all cases. There were no intraprocedural or device-related deaths. In-hospital and 30-day mortality were 10%; 1-year cumulative mortality was 30% (all deaths were of cardiovascular causes).

Conclusions
In the CS group, in-hospital and 30-day outcomes were poor, in line with the existing evidence, illustrating the severity, complexity and heterogeneity of this clinical scenario. Acceptable rates of major device-related complications were observed. In the HR-PCI cohort, the use of Impella to provide hemodynamic support was feasible and safe. Long-term results express the severity of the underlying disease and the patients’ complexity. With the expanding use of the device, tools to identify the most suitable candidates for Impella support are warranted.