Left ventricular assist device exchange: the Toronto General Hospital experience

Abstract

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.Contexte : À mesure que la durée d'utilisation des dispositifs d'assistance ventriculaire gauche (DAVG) augmente, plusieurs complications nécessitant un remplacement du dispositif peuvent survenir. À notre connaissance, il s'agit du premier rapport canadien concernant le remplacement des DAVG implantables.Méthodes : Nous avons passé en revue de manière rétrospective les cas individuels consécutifs de patients à qui on a implanté un DAVG entre juin 2006 et octobre 2015 à l'Hôpital Général de Toronto.Résultats : En tout, 122 patients ont reçu un DAVG pendant la période de l'étude. Huit patients ont eu besoin d'un remplacement de DAVG et 1 patient a eu besoin de 2 remplacements (9 sur 122, 7,3 %). Sept dispositifs HeartMate II (HMII), 1 dispositif HVAD et 1 dispositif DuraHeart ont été remplacés. Deux de ces remplacements sont survenus peu de temps après la pose initiale du dispositif, tandis que les 7 autres se sont produits plus tardivement (dans les 8 à 623 jours suivants). Six remplacements ont été effectués en raison d'une thrombose de la pompe. Parmi les 3 remplacements effectués pour d'autres raisons, 1 dispositif HMII a été remplacé en raison d'un bris de la ligne d'activation, 1 dispositif DuraHeart a présenté une obstruction précoce du flux entrant nécessitant la pose d'un HMII...

Recurrent pump thrombosis is common after axial continuous-flow left ventricular assist device exchange

“…The results of our study demonstrate that HeartMate II to HeartMate II pump exchange is associated with survival that compares well with published results from other investigators as well as with published results after primary LVAD implantation. 1,3,4,13 Various techniques for surgical approach to the device, including subcostal and subxiphoid, have been compared to the traditional sternotomy. 6,14,15 Although there is some evidence of superiority of subcoastal approach, several authors have questioned these conclusions based on a significant selection bias in these studies.…”

“…We transplanted three patients within the first 6 months post pump exchange—before the observed median time for device thrombosis recurrence. Tsubota et al 4 reviewed their institutional experience with six patients with HeartMate II who presented with pump thrombosis and underwent exchange to a second HeartMate II. Of six patients, two were transplanted, two died, and two were reported alive on the second pump 21 and 119 days after the exchange.…”

“…3 Furthermore, patients after exchange experience less freedom from infection and neurological dysfunction when compared to the initial implant. 4,5 In patients who undergo device exchange for pump thrombosis, there is a risk for recurrent LVAD thrombosis over time that has been suggested in previous studies but not precisely quantified. 6,7 Despite the fact that new generation centrifugal-flow pumps recently overtook axial-flow devices as the predominant choice for durable continuousflow left ventricular support and there is gradual attrition due to transplantation, explantation/defunctionalization for recovery and death, the number of patients implanted with HeartMate II device worldwide remains substantial.…”

A Rising Hope of an Artificial Heart: Left Ventricular Assisted Device - Outcome, Convenience, and Quality of Life

“…In summary, LVAD is an excellent choice in patients waiting for cardiac recovery time. Regarding traditional HFrEF patients who are our main focus in this review, ejection fraction improvement after LVAD treatment alone does not have much impact on outcome and has a questionable improvement in patients’ quality of life [20].…”

“…A prolonged course of ICU management with multiple blood works before and after LVAD treatment also have an impact on costs as it usually requires the pre-assessment of basic hemodynamic parameters along with ICU stay expenses. There are also additional costs due to LVAD device implantation by the surgical team, post-LVAD operative care requiring extended ICU management with multiple consultation teams, and several follow-up tests [19-20]. Re-hospitalization due to device-related complications after LVAD implantation, has a significant impact on the quality of life, both for the patients and the caregivers.…”