Mechanical circulatory support with impella in patients with non-acute myocardial infarction related cardiogenic shock

Abstract

Abstract Background Percutaneous left ventricular assist devices such as the Impella pump, are used to hemodynamically stabilize patients with cardiogenic shock (CS) caused by acute myocardial infarction (AMI) until cardiac function has recovered after revascularization. Whether Impella mechanical circulatory support (MCS) is effective in stabilizing patients with CS not caused by AMI has so far not been thoroughly investigated. Purpose The aim of this study is to analyze whether MCS with Impella is effective to stabilize patients with non-AMI related CS compared to patients with AMI related CS. Method We retrospectively analyzed 106 patients with CS and Impella support in the years from 2011 to 2018. Efficacy to stabilize the patient was assessed by laboratory values such as lactate, hemodynamic parameters and clinical scores. The difference in mortality was calculated with the Log-Rank-Test, comparing Kaplan-Meier curves. Results 36 patients suffered from non-AMI CS and in 70 patients CS was caused by AMI. Regarding the clinical scores and hemodynamic parameters, both groups were severely ill, with no significant difference in APACHE II score, with a mean score of 17.9 in the non-AMI group compared to 20.5 in the AMI-group (p=0.103), the SOFA score (mean score of 6.3 in non-AMI group vs 6.8 in AMI group, p=0.467) and cardiac index (mean CI of 1.9 l/min/m2 in non-AMI group vs 2.2 l/min/m2 in AMI group, p=0.176). There was a comparable mean decrease in lactate levels in both groups 48 hours after initiation of MCS, from initially 4.1 mmol/l to 1.7 mmol/l (p<0.001) in the non-AMI group and from initially 3.6 mmol/l to 2.2 mmol/l (p=0.025) in the AMI group. The non-ACS group exhibited a trend of lower mortality compared to the AMI group, with 47% in the non-AMI group and 57% in the AMI group (p=0.067). In multivariate analysis, age, lactate levels, cardiopulmonary resuscitation, low platelets and higher doses of inotropes and vasopressors were independent predictors for mortality. An upgrade to LVAD was performed for 22% of the non-AMI group and for 6% of the AMI group (p=0.020). Conclusion Impella support is effective to hemodynamically stabilize patients with non-AMI related CS. Therefore, MCS can be used as bridge to recovery or enables further treatment options as upgrade to longterm mechanical support devices. Funding Acknowledgement Type of funding source: None