P104: Using Bicarbonate based purge solution (BBPS) as the sole anticoagulant in Impella 5.5-A novel approach

Abstract

The Impella® (Abiomed; Danvers, MA) pumps are percutaneous, transvalvular mechanical circulatory support (MCS) devices that propel blood from left ventricle to aorta that are used to augment cardiac output in management of high-risk percutaneous coronary intervention (HRPCI), acute heart failure, or cardiogenic shock. These systems utilize a flow of purge fluid that runs countercurrent to the blood flow which prevents inline thrombosis and protein deposition. Guidelines generally recommend heparin-dextrose purge fluid, with BBPS reserved for patients with heparin intolerance or active bleeding. We present the first case of use of BBPS as an elective choice for purge fluid in a patient with severe cardiogenic shock. Patient is 56-year-old male with known history of hypertension, diabetes and hyperlipidemia who presented with acute onset shortness of breath secondary to acute heart failure in the setting of myocardial infarction. He underwent a HRPCI for a non revascularizable three vessel coronary artery disease. He was readmitted for cardiogenic shock complicated with ventricular tachycardia, fibrillation and high risk of sudden cardiac death, necessitating inpatient transplant evaluation. Left heart catheterization showed pulmonary artery pressure of 59/63, wedge of 29 and cardiac index of 2 on 0.125mcg/kg/hr of milrinone. He received aggressive diuresis, antiarrhythmics and inotropic support. With increasing milrinone requirement, Impella 5.5 was placed and his antiplatelet regimen was changed from oral prasugrel to intravenous cangrelor with aspirin. A clinical decision was made to use BBPS instead of heparin purge, based on institutional experience and clinical data. Purge pressure, flow, lactate dehydrogenase and hematocrit have remained stable about 1.5ml/hr, 500mm Hg, 230U/L and 30% respectively for 22 days post-impella placement as the patient awaits transplantation Limited retrospective studies and recent animal data from ABIOMED, have shown no change in purge pressure or flow with BBPS. However, most of the data remains limited to use in heparin intolerant patients. Our experience has indicated the possibility to use BBPS without systemic anticoagulation with no short-term complication.