Left ventricular assist device exchange: the Toronto General Hospital experience

Background: As support times for left ventricular assist devices (LVADs) become longer, several complications requiring device exchange may occur. To our knowledge, this is the first Canadian report regarding implantable LVAD exchange. Methods: We retrospectively reviewed the cases of consecutive, unique patients implanted with an LVAD between June 2006 and October 2015 at Toronto General Hospital. Results: In total, 122 patients were impanted with an LVAD during the study period. Eight patients required LVAD exchange, and 1 patient had 2 replacements (9 of 122, 7.3%). There were 7 HeartMate II (HMII), 1 HVAD and 1 DuraHeart pumps exchanged. Two of these exchanges occurred early at the time of initial implant, whereas 7 occurred late (range 8-623 d). Six exchanges were made owing to pump thrombosis. Of the 3 exchanges made for other causes, 1 HMII exchange was owing to a driveline fracture, 1 DuraHeart patient had early inflow obstruction requiring exchange to HMII at the initial implant, and the third had a suspected inflow obstruction with no evidence of thrombosis at the time of the procedure. The mean support time before exchange was 225 days, and time from exchange to transplant, death or ongoing support was 245 days. Three patients were successfully bridged to transplant, and at the time of data collection 2 were supported awaiting transplant. Three patients died after a mean duration of 394.3 days (range 78-673 d) of support postreplacement. Four cases were successfully performed using a subcostal approach. Conclusion: Pump thrombosis is the most common cause for LVAD exchange, which can be performed with acceptable morbidity and mortality. The subcostal approach may be the preferred procedure for an HMII exchange when indicated.