1121 USE OF IMPELLA 5.0 AS BRIDGE TO LVAD IN CARDIOGENIC SHOCK: REPORT OF TWO CASES
Authors: Marcelli Chiara , Sabatino Mario , Spitaleri Giosafat , Masetti Marco , Martin-suarez Sofia , Loforte Antonio , Galiè Nazzareno , Potena Luciano 
Published: December 2022

Abstract

Background
Left ventricle assist devices (LVAD) are an option in end stage heart failure (HF) as bridge to or alterative to heart transplantation. Adequate compensation of patient is key to obtain a good outcome. We report two cases of Impella 5.0 bridge to LVAD in patients with cardiogenic shock (CS) in which intra-aortic balloon pump (IABP) failed to obtain hemodynamic stability.

Case series
A) A 60 years old man developed CS after anterior myocardial infarction treated with primary PCI of left main coronary artery. At presentation patient was hypotensive with signs of hypoperfusion and pulmonary congestion: systemic blood pressure (SBP) 80/60 mmHg despite inotropic drugs, blood lactates 4 mmol/l, urine output of last 6 hours 0,4 ml/kg/h (INTERMACS 2). Echocardiography showed severe left ventricle disfunction with LVEF 15%, severe mitral regurgitation (MR) and sPAP 45 mmHg. Therefore, IABP was implanted. Right heart catheterization (RHC) showed pulmonary hypertension and high filling pressure with reduced cardiac output and increased pulmonary vascular resistance (mPAP 39 mmHg, CPWP 28 mmHg, CO 3 l/min, PVR 3.7 uW, PAPi 2.8); X-ray chest showed persistence of pulmonary congestion. After 9 days on IABP, patient underwent Impella 5.0 implant through right axillary artery as bridge to durable LVAD. Pulmonary artery catheter (PAC) monitoring showed reduction of pulmonary hypertension with mPAP 35 mmHg and CPWP 17 mmHg and chest X-ray documented improvement of lung congestion. Bedside rehabilitation was started. Two weeks later patient underwent LVAD HM3 implantation as destination therapy. The patient was discharge home on post-operative day 55. B) After subacute myocardial infarction with three-vessels disease, a 53 y.o. man developed severe congestive HF with severe left ventricular disfunction and was referred to our institution for evaluation. RHC showed pulmonary hypertension with pre-capillary component not reversible after enoximone test, contraindicating heart transplantation. Therefore, patient was candidate to receive LVAD as bridge strategy. Echocardiography at admission showed dilated and hypokinetic left ventricle (EDV 200 ml, LVEF 17% severe MR, sPAP 60 mmHg) and dilated and hypokinetic RV. During hospitalization the patient experienced CS with SBP 62/45 mmHg, 6-hours urine output of 1,4 ml/kg/h and blood lactates 8.3 mmol/l (INTERMACS 1) so femoral IABP was implanted. RHC was repeated both without IABP support (mPAP 37 mmHg, PCWP 28 mmHg, CO 1.4 l/min, CI 0.9 l/min/m2) and with IABP support (mPAP 32 mmHg, PCWP 18 mmHg, CO 2.15 l/min, CI 1.4 l/min/m2). During the following stay he developed S. Aureus sepsis requiring prolonged antibiotic therapy. Expecting a long time before LVAD, axillary Impella 5.0 was implanted in order to unload the LV and allow early patient mobilization. Subsequent PAC monitoring showed improvement of pulmonary hypertension and cardiac index (mPAP 24 mmHg, PCWP 9 mmHg, CO 5.1 l/min with Impella flow 4.2 l/min, CI 3.2 l/min/m2). After 11 days, patient received LVAD HVAD with uneventful course and was discharged on post-operative day 22.

Conclusions
Impella 5.0 is a surgically implanted intravascular microaxial blood pump that delivers up to 5 l/min of blood from LV to aorta, leading to improved perfusion and more efficient LV unloading. In patients with CS this can help to obtain better decongestion, RV recovery, and favorable preconditioning before LVAD implant. Moreover, axillary access allows better patient mobilization preventing cachexia after long time hospitalization.