Inflow Cannula Positioning of the HeartWare Device is Not Associated
with Thomboembolic Events
Abstract
BACKGROUND Prior studies have suggested that LVAD implantation technique
and positioning may be associated with subsequent thromboembolic
complications. This study evaluated the impact of inflow cannula
positioning of the HeartWare LVAD (HVAD) on clinical outcomes. METHODS
Adults undergoing primary HVAD implantation between 2009-2018 at a
single center were reviewed. HVAD position parameters were calculated
from plain chest radiographs and included cannula angle, pump depth, and
pump area. These were measured at the day of HVAD implant, at 1 month
post-HVAD, and at 6 months post-HVAD. Changes in these parameters over
time were measured. Multivariable analysis was also conducted to
evaluate associations between pump position parameters on the day of
implant and one-year composite outcome of thromboembolic complication
(embolic stroke or pump thrombosis) and death. RESULTS 159 HVAD
recipients were included with a median follow up of 2.6 years (IQR 1.3 -
4.8 years). Pump area decreased from immediate post-HVAD implantation to
one-month follow up (-0.7 cm2; p=0.002), but no significant changes were
noted with other position parameters. Increasing preoperative serum
creatinine level (HR 1.46, 95% CI 1.03 - 2.08, p=0.034) was associated
with increased hazards for the composite outcome in multivariable
analysis. Cannula angle, pump depth, nor pump area were associated with
the one-year composite outcome, readmission, or other one-year
complications including thromboembolic events or mortality when
separately modeled. CONCLUSION This review of HVAD recipients
demonstrates device position as assessed by chest X-ray does not have
significant predictive associations with one-year outcomes.