Single center first year experience and outcomes with Impella 5.5 left ventricular assist device.

BACKGROUND: The Impella 5.5® was approved by the FDA for use for mechanical circulatory support up to 14 days in late 2019 at limited centers in the United States. Our single center's experience with Impella 5.5® can expand the overall understanding for achieving successful patient outcomes as well as provide support for the expansion of its FDA-approved use. METHODS: This study is an IRB-approved single-center retrospective cohort analysis of hospitalized adult patient characteristics and outcomes in cases where the Impella 5.5® was utilized for mechanical circulatory support. RESULTS: A total of 26 implanted Impella 5.5® devices were identified in 24 hospitalized patients at our institution from January 2020 to January 2021. The overall survival rate during index hospitalization was 75%. Eleven Impella 5.5® devices were identified in 10 patients with an average device implantation greater than 14 days. Average device implantation for this subgroup was 27 days with a range of 15-80 days. Survival rate for Impella 5.5® use greater than 14 days was 67%. In the entire cohort and subgroup of device implantation > 14 days, evidence of end organ damage improved with Impella 5.5® use. Complications in our cohort and subgroup of device implantation > 14 days were similar to previously reported complication incidence of axillary inserted LVAD devices. CONCLUSIONS: Our institution's experience with the Impella 5.5® has been strongly positive with favorable outcomes and helps to establish the Impella 5.5® as a viable option for mechanical circulatory support beyond 14 days.

Association of acquired von Willebrand syndrome with AL amyloidosis.

Acquired loss of functional von Willebrand factor (VWF) has been termed the acquired von Willebrand syndrome (AVWS). AVWS is a rare adult-onset bleeding diathesis that is clinically similar to congenital von Willebrand disease (VWD), and occurs with a variety of autoimmune, lymphoproliferative, or myeloproliferative disorders. We have identified four patients with AVWS in association with immunoglobulin light chain (AL) amyloidosis. These patients, lacking any pre-existing or family history of abnormal bleeding, developed cutaneous, mucosal, or gastrointestinal bleeding in the course of their disease without deficiency of clotting factor X or other factors; the activated partial thromboplastin time (aPTT) was prolonged in three out of the four cases. Despite normal VWF antigen levels, VWF ristocetin cofactor activity (VWF:RCo) was low. Electrophoresis patterns of high molecular weight (HMW) VWF multimers were abnormal in two of the four cases. Two of the patients were treated with high-dose intravenous melphalan followed by autologous stem cell transplantation (HDM/SCT) and achieved hematologic remission. In these two patients, the bleeding diathesis improved and the coagulation parameters normalized, confirming a causal relationship between the plasma cell dyscrasia and the AVWS. AVWS should be considered in AL amyloidosis patients with hemorrhagic diatheses and normal clotting factor levels.