Favorable Outcomes with Ventricular Assist Device Exchange

The VAD Journal: The journal of mechanical assisted circulation and heart failure Peer-Reviewed Original Research Favorable Outcomes with Ventricular Assist Device Exchange Megan Carroll1*, Meghan Tooman2, Markian Bochan3, Christopher Salerno4, and Ashwin Ravichandran4 1 Indiana University School of Medicine, Indianapolis, IN Statistical Research Solutions, LLC., Indianapolis, IN 3 Infectious Disease of Indiana and St. Vincent Hospital, Indianapolis, IN 4 St. Vincent Heart Center, Indianapolis, IN 2 Citation: Carroll M. et al. (2019) “Favorable Outcomes with Ventricular Assist Device Exchange.” The VAD Journal, 5. doi: https://doi.org/10.13023/VAD.201 9.05 Editor-in-Chief: Maya Guglin, University of Kentucky Received: January 25, 2019 Accepted: March 11, 2019 Published: March 12, 2019 © 2019 The Author(s). This is an open access article published under the terms of the Creative Commons AttributionNonCommercial 4.0 International License (https://creativecommons.org/lice nses/by-nc/4.0/), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided that the original author(s) and the publication source are credited. *Corresponding author: Abstract Left ventricular assist device (LVAD) therapy remains a vital therapeutic option for patients with end-stage heart failure. Unfortunately, adverse events can occur and progress to require consideration for device exchange once the failure of medical management becomes evident, especially when heart transplantation is not possible in a timely manner. The aim of this analysis is to describe the incidence and outcomes of LVAD exchanges at our institution. Between April 2008 and May 2017, 397 patients underwent LVAD implantation, with 32 of those patients subsequently receiving exchange upon the recommendation of our multidisciplinary team due to refractory infection (n=12), device malfunction (n=5), hemolysis (n=9) and pump thrombosis (n=6). The average time from index implant to exchange was 580.6 days, with an average length of stay of 18.2 days. Survival at 3 months was 84.4%, 75.0% at 1 year and median at 8.3 years after exchange. The most common adverse events, occurring in less than 1/3 of the population, included bleeding, infection and stroke. This study suggests that LVAD exchange can be an effective and definitive mechanism for the treatment of otherwise potential fatal pump complications in highly select patients. Funding: Not applicable Competing interests: Not applicable Keywords: Left ventricular assist device (LVAD), device infections, advanced heart failure, cardiac transplantation, VAD exchange The VAD Journal: https://doi.org/10.13023/vad.2019.05 Page 1 of 10 The VAD Journal: The journal of mechanical assisted circulation and heart failure Introduction Heart failure is the leading cause of hospitalizations annually, with recent estimates of Americans 40 years or older facing a 20% lifetime risk, a prevalence of over 9 million Americans by 2030. 1 A significant proportion of patients will unfortunately go on to fail medical therapy, requiring the use of advanced treatment strategies for end-stage heart failure. While many patients at this stage can be successfully treated with transplantation, a large number have comorbidities that prevent eligibility for the therapy, or have unacceptably prolonged wait times, thereby making durable left ventricular assist device (LVAD) support their most viable therapeutic option.2-3 However, serious complications necessitating device exchange can include pump thrombosis, hemolysis and infection, posing challenging management scenarios for those who remain ineligible for transplantation after LVAD or have a prolonged wait time and experience a complication while on mechanical support. 4 Risk factors for adverse events leading to exchange commonly include deviation from standardized implant and immediate/long-term management techniques, advanced age, immunosuppressed states such as diabetes, elevated blood pressure and patient non-compliance.5-8 Methods to improve outcomes and decrease adverse events include careful instruction on routine maintenance of the driveline, accurate monitoring of anticoagulant and antiplatelet therapy and aggressive antibiotic therapies when indicated (oral and parenteral), guided by culture data in consultation with an infectious disease specialist. Unfortunately, some patients still progress to consideration for LVAD exchange once the failure of medical management becomes evident, especially when transplantation is not possible in a timely manner. This analysis describes the incidence and outcomes of LVAD exchange procedures at our institution. Methods A retrospective analysis of our institution’s LVAD database was performed. During a 9-year period, 397 patients underwent LVAD implantation between April 2008 and May 2017, with 32 of those patients subsequently receiving LVAD exchange between September 2009 and March 2017. Only initial pump exchange patients were included in the reviewed cohort. The reasons for exchange included: refractory infection, evidence of device malfunction, hemolysis and pump thrombosis. Surgical approach varied based on device and indication for exchange and included subcostal or full sternotomy approaches. Descriptive analysis, Kaplan-Meier survival estimates and time to first event were then calculated. Outcomes of interest included death, hemolysis, pump thrombosis, stroke, right heart failure, bleeding and infection. The time between initial implant and exchange, length of post-operative hospital stay, discharge location and average time to follow-up after discharge were monitored to provide an objective standard for post-operative patient management.The decision to exchange the device was defined by the failure of medical therapy as determined by an interdisciplinary team of cardiologists, infectious disease specialists and surgeons. Specific criteria for exchange in cases of infection included refractory The VAD Journal: https://doi.org/10.13023/vad.2019.05 Page 2 of 10 The VAD Journal: The journal of mechanical assisted circulation and heart failure infection as guided by physical examination, laboratory, culture and imaging data despite appropriate culture-guided antibiotic therapy. Ongoing laboratory and pump parameters were used to define hemolysis and pump thrombosis according to the accepted Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) definitions.3 Infection data, concomitant medications and antibiotic history were collected to investigate the most common risk factors and pathogens involved and any possible correlations with surgical outcomes. The surgical approach focused on incision type – patients required sternotomy when complete device extraction was necessary to address their reason for pump exchange. In cases of infection, full sternotomy was only performed when infection ascended beyond the pump pocket. Result (...truncated)