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Updated: Feb 8, 2026

Use of a Percutaneous Ventricular Assist Device/Left Atrium to Femoral Artery Bypass System for Cardiogenic Shock
Published on: August 16, 2021
Controller and battery changes due to technical problems related to the HVAD® left ventricular assist device - a
Emil Najjar1,2, Ann Hallberg Kristensen3, Tonje Thorvaldsen4,3
1Department of Medicine, Unit of Cardiology, Karolinska Institutet, Karolinska University Hospital, S3:02, Stockholm, 17176, Sweden. Emil.Najjar@sll.se.
Background:
The use of left ventricular assist devices (LVADs) has increased in the last decade. Major complications have been well described, but there is no data on device alarms and actual or threatening malfunction which impair quality of life and may impair outcomes. This study describes the technical problems related to the use of the HVAD® left ventricular assist device in a single center.
Methods:
We retrospectively reviewed device malfunctions and outcomes in 22 patients with HVAD® left ventricular assist device followed at Karolinska University Hospital between 2011 and 2016. Device malfunction was defined by INTERMACS as a failure of one or more of the components of the LVAD system. The primary outcome was defined as death or hospitalization or unplanned urgent clinic visit due to device alarm of unknown significance or actual or threatening malfunction. Separate secondary outcomes were malfunction resulting in controller exchange and malfunction resulting in battery change. Exploratory outcomes were death, transplantation, or explantation because of recovery.
Results:
Median age was 59 years and 19% were women. Over a mean follow-up time of 1.7 years (37 patient-years), the primary outcome occurred 30 times (0.8 events per patient-year; 0 deaths, 2 hospitalizations and 28 un-planned clinic visits). Secondary outcomes were 41 device malfunctions for 14 patients requiring 45 controller exchanges in 12 patients (1.1 events per patient-year) and 128 battery changes in 12 patients (3.5 events per patient-year). Exploratory outcomes were 8 deaths (36.4%), 7 transplantations (31.8%) and 2 explants due to recovery (9.1%).
Conclusion:
The use of HVAD® was associated with technical problems requiring frequent un-planned clinic visits and changes of controller and/or batteries. There were no deaths due to device malfunction. Further studies are warranted to evaluate the risk of device malfunction and associated reductions in quality of life and cost.
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