Improved Approach With Subcostal Exchange of the HeartMate II Left Ventricular Assist Device: Difference in On and Off Pump?

BACKGROUND: The HeartMate II (St. Jude Medical, Inc, St. Paul, MN [previously Thoratec]) left ventricular assist device (LVAD) exchange has traditionally involved a redo sternotomy. Alternate minimally invasive subcostal approaches have the advantage of avoiding sternal reentry, excessive bleeding, and prolonged recovery.

METHODS: This retrospective review included patients who underwent an exchange from May 2009 to March 2016. The patients were divided into three cohorts: (1) redo sternotomy, (2) subcostal approach involving cardiopulmonary bypass (CPB) (ON-CPB SC), and (3) subcostal approach off the CPB pump (OFF-CPB SC). Data pertaining to patients' baseline characteristics and outcomes were collected and analyzed.

RESULTS: From May 1, 2009 to July 31, 2016, 33 HeartMate II LVAD exchanges were performed. There were 11 redo sternotomies and 22 subcostal exchanges, 12 of which were in the OFF-CPB SC group. There was no significant difference among the groups in terms of age (p = 0.75), sex (p = 0.95), and indication for exchange (p = 0.94). There was a higher red blood cell transfusion requirement within the sternotomy cohort (p < 0.001). The median time to extubation and the intensive care unit length of stay were significantly shorter in the OFF-CPB SC group (1 and 2.5 days, respectively) than in the sternotomy (2.5 and 21 day, respectively) and ON-CPB SC groups (1.5 and 5 days, respectively). The 30-day and 90-day survival rates were equivalent among the cohorts.

CONCLUSIONS: Exchange of the HeartMate II LVAD can be accomplished with significantly improved recovery time and transfusion requirement through a less invasive subcostal approach when compared with sternotomy. The subcostal approach can be performed safely both on and off cardiopulmonary bypass.