Centrifugal-flow pumps improve complication free survival compared to axial flow-pumps

Originally Published By 2 Minute Medicine®. Reused on MPR with permission.

1. Advanced heart failure patients randomized to receive centrifugal-flow pumps demonstrated higher rates of 2-year survival free of disabling stroke or reoperation to remove or replace their device compared to patients randomized to receive axial-flow pumps.

2. There were also lower rates of pump thrombosis among patients assigned to the centrifugal-flow pump arm compared to those in the axial-flow pump arm.

Evidence Rating Level: 1 (Excellent)

Study Rundown: Left ventricular assist systems (LVAS) are devices used to assist patients with advanced heart failure, either as a bridge therapy while patients await cardiac transplantation or as a destination therapy. Traditional axial-flow pump models carry a serious risk of pump thrombosis formation. The current trial, titled MOMENTUM 3, compared the efficacy of a fully magnetically levitated centrifugal-flow pump to the axial-flow pump model in patients with advanced heart failure. Patients were followed for 2 years to primarily assess survival free of disabling stroke or reoperation. The centrifugal-flow pump demonstrated superiority compared to the axial-flow pump with higher complication-free survival rates, lower pump thrombosis formation rates, and lower incidences of stroke.

This study's strengths include its long-term follow-up period. Limitations include its non-blinded nature which could have introduced bias into the results. Nevertheless, this study demonstrates a significant step forward in the ability to treat advanced heart failure.

Click to read the study, published in NEJM

Relevant Reading: A Fully Magnetically Levitated Circulatory Pump for Advanced Heart Failure

Related Articles

In-Depth [randomized control trial]: This non-blinded, randomized, intention-to-treat trial enrolled 366 patients between 2014 to 2015 into one of two study arms: centrifugal-flow pump group (n = 190) and axial-flow pump group (n = 176). Eligible patients had advanced heart failure refractory to medical management, and notable exclusion criteria included active infection, irreversible end-organ disfunction, or excessive biventricular support. The primary endpoint of this study was survival at 2 years free of disabling stroke or reoperation to replace or remove a pump. At two years, the primary endpoint was reached in more patients that were assigned to the centrifugal flow pump group as compared to those assigned to the axial flow pump group (79.5% vs 60.2%; hazard ratio [HR], 0.46; confidence interval [CI], 0.31 to 0.69; p < 0.001 for noninferiority, p < 0.001 for superiority). This difference was driven by lower rates of pump reoperation or removal among patients in the centrifugal-flow pump group (1.6% vs 17.0%; HR, 0.08, 95% CI, 0.03 to 0.27; p < 0.001). The centrifugal-flow pump group also had higher actuarial event free survival when Kaplan Meier tests were performed (77.9% vs 56.4%; p < 0.001). Suspected pump thrombosis occurred in 2 patients (1.1%) in the centrifugal-flow pump group compared to 27 patients (15.7%) in the axial flow pump group (HR, 0.06; 95% CI, 0.01 to 0.26; p < 0.001). There were 22 strokes among 19 patients (10.1%) in the centrifugal-flow pump group compared to 43 strokes in 33 patients (19.2%) in the axial-flow pump group (HR, 0.47; 95% CI, 0.27 to 0.84; p = 0.02).

Image: PD

©2018 2 Minute Medicine, Inc. All rights reserved. No works may be reproduced without expressed written consent from 2 Minute Medicine, Inc. Inquire about licensing here. No article should be construed as medical advice and is not intended as such by the authors or by 2 Minute Medicine, Inc.