The Impact of Prolonged Impella 5.5 Support on Mortality Following Orthotopic Heart Transplantation in the United States
Presented During: Welcome Reception and Poster Competition | Sponsored by: TransMedics
Perelman School of Medicine, University of Pennsylvania
Bethesda, MD
United States - Contact Me
David Rekhtman is a 4th year medical student at the Perelman School of Medicine at the University of Pennsylvania. He is planning to pursue a career in academic surgery and is particularly interested in heart transplantation and temporary mechanical circulatory support devices.
Friday, September 20, 2024: 5:00 PM - 6:30 PM
Omni King Edward Hotel
Description
Objective: An evolving strategy and trend in heart transplantation is the utilization of temporary mechanical circulatory support in the pre-operative period. Axial flow pump devices, such as the Impella 5.5, have increasingly been used in the setting of cardiogenic shock as a bridge to transplantation. Although the device was initially approved for a period of 14 days, little has been reported regarding the safety of prolonged use and its impact on post-transplant outcomes. The current study aims to compare post-transplantation mortality based on duration of support with the Impella 5.5.
Methods: Adult patients listed for first-time isolated heart transplantation between October 18, 2018 and January 1, 2023 were identified in the United Network for Organ Sharing database. Those that had been supported by the Impella 5.5 and subsequently transplanted were included in this study. Patients who were on multiple forms of temporary mechanical circulatory support were excluded. A histogram of support duration was developed to determine an appropriate cut-off in cohort development (Figure 1a). Based on the distribution of the data, as well as the current FDA policy, patients were stratified based on duration of Impella 5.5 support with a cut-off of 14 days. Baseline characteristics and post-transplant outcomes were compared utilizing the Kruskal-Wallis rank test and chi-squared analysis for continuous and categorical variables, respectively. Further, Kaplan-Meier estimates as well as univariable and multivariable Cox proportional hazards were used to assess 1-year mortality.
Results: Of the 865 patients included in this study, 331 (38%) were supported for less than 14 days while the remaining 534 (62%) required more than 14 days of Impella 5.5 support. Cohorts were similar with regard to age, sex, insurance status, body mass index, ABO blood group, underlying cardiomyopathy etiology, and listing status (all p>0.05). Notably, patients with shorter Impella 5.5 support duration had lower cardiac output (3.8 vs. 4.1 L/min, p=0.005) and more ventilator requirements (3% vs. 1%, p=0.044). These patients were also less likely to be on Impella 5.5 support at time of listing (57% vs. 66%, p=0.014). Although donor hearts were procured from further distances for patients on shorter support (287 vs. 236 miles, p=0.018), post-transplant outcomes including dialysis, graft rejection, pacemaker requiring, stroke, and death at time of last follow-up were not different (all p>0.05). Similarly, no difference in 1-year mortality was found between the two cohorts (Figure 1b, log-rank test p=0.252). On univariable and multivariable Cox regression models, prolonged Impella 5.5 support was not predictive of 1-year mortality (HR 0.71 [0.39-1.29]; HR 0.86 [0.43-1.72]).
Conclusions: Prolonged Impella 5.5 support for patients awaiting heart transplantation is not associated with a difference in post-transplant outcomes or 1-year mortality. As patients on the heart transplantation waiting list await a donor heart, prolonged axial-flow pump support may be a reasonable bridging strategy as experience in managing these critically ill patients grows.
Authors
David Rekhtman (1), Amit Iyengar (2), Cindy Song (1), Michaela Asher (1), Noah Weingarten (2), Max Shin (2), Samuel Kim (2), John DePaolo (2), Mauer Biscotti (2), Marisa Cevasco (2)
Institutions
(1) Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, (2) Division of Cardiac Surgery, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA
Methods: Adult patients listed for first-time isolated heart transplantation between October 18, 2018 and January 1, 2023 were identified in the United Network for Organ Sharing database. Those that had been supported by the Impella 5.5 and subsequently transplanted were included in this study. Patients who were on multiple forms of temporary mechanical circulatory support were excluded. A histogram of support duration was developed to determine an appropriate cut-off in cohort development (Figure 1a). Based on the distribution of the data, as well as the current FDA policy, patients were stratified based on duration of Impella 5.5 support with a cut-off of 14 days. Baseline characteristics and post-transplant outcomes were compared utilizing the Kruskal-Wallis rank test and chi-squared analysis for continuous and categorical variables, respectively. Further, Kaplan-Meier estimates as well as univariable and multivariable Cox proportional hazards were used to assess 1-year mortality.
Results: Of the 865 patients included in this study, 331 (38%) were supported for less than 14 days while the remaining 534 (62%) required more than 14 days of Impella 5.5 support. Cohorts were similar with regard to age, sex, insurance status, body mass index, ABO blood group, underlying cardiomyopathy etiology, and listing status (all p>0.05). Notably, patients with shorter Impella 5.5 support duration had lower cardiac output (3.8 vs. 4.1 L/min, p=0.005) and more ventilator requirements (3% vs. 1%, p=0.044). These patients were also less likely to be on Impella 5.5 support at time of listing (57% vs. 66%, p=0.014). Although donor hearts were procured from further distances for patients on shorter support (287 vs. 236 miles, p=0.018), post-transplant outcomes including dialysis, graft rejection, pacemaker requiring, stroke, and death at time of last follow-up were not different (all p>0.05). Similarly, no difference in 1-year mortality was found between the two cohorts (Figure 1b, log-rank test p=0.252). On univariable and multivariable Cox regression models, prolonged Impella 5.5 support was not predictive of 1-year mortality (HR 0.71 [0.39-1.29]; HR 0.86 [0.43-1.72]).
Conclusions: Prolonged Impella 5.5 support for patients awaiting heart transplantation is not associated with a difference in post-transplant outcomes or 1-year mortality. As patients on the heart transplantation waiting list await a donor heart, prolonged axial-flow pump support may be a reasonable bridging strategy as experience in managing these critically ill patients grows.
Authors
David Rekhtman (1), Amit Iyengar (2), Cindy Song (1), Michaela Asher (1), Noah Weingarten (2), Max Shin (2), Samuel Kim (2), John DePaolo (2), Mauer Biscotti (2), Marisa Cevasco (2)
Institutions
(1) Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, (2) Division of Cardiac Surgery, Department of Surgery, Hospital of the University of Pennsylvania, Philadelphia, PA