Acute Hemodynamic and Echocardiographic Consequences of Impella 5.5 Placement in Patients With Advanced Cardiogenic Shock

We sought to investigate the hemodynamic and echocardiographic consequences of the Impella 5.5 during the acute perioperative period. A retrospective analysis of patients who underwent device implantation at our institution between January 2021 and June 2023 was performed. Hemodynamic and echocardiographic changes were modeled as linear mixed models with random intercepts for patient and fixed as well as random effects of time. Of 87 patients identified, most were male (72, 83%) with nonischemic cardiomyopathy (44, 51%). In the first two postoperative days, the median cardiac output increased by 1.2 L/min ( p < 0.05), although the median Impella flow remained at 4.1 L/min. Mean pulmonary artery pressures (32 vs. 27 mm Hg, p < 0.05) and vasoactive inotrope scores (5.6 vs. 3.7, p < 0.01) were modestly reduced. Significant echocardiographic improvement was noted in 61% and 71% of patients with significant preoperative mitral or tricuspid regurgitation, respectively. However, no changes in ejection fraction, left ventricle (LV) diameter, or right ventricular function were noted (all p > 0.05). At 30 days, 27 (31%) patients were transplanted and 13 (15%) were bridged to a durable left ventricular assist device (LVAD). We conclude that in the acute phase following Impella implantation, LV offloading, reductions in pulmonary artery pressures, and improvement in valvular regurgitation are seen without changes to ventricular geometry.