Epidemiology, Outcomes, and Effects of Device Flow Type on Ventricular Assist Devices (VAD) Infections: An IMACS Registry Analysis.
Xie R, Cowger J, Kirklin JK, Hannan MM, Goldstein DJ, and Aslam S. Epidemiology, Outcomes, and Effects of Device Flow Type on Ventricular Assist Devices (VAD) Infections: An IMACS Registry Analysis. J Heart Lung Transplant 2019; 38(4 Suppl):S101.
J Heart Lung Transplant
Purpose: Infection remains an important cause of morbidity and mortality in continuous flow ventricular assist device (CF-VAD) recipients. It is unclear if flow type (axial or centrifugal) is associated with VAD infection and post-infection outcomes. This study aimed to investigate the device flow-type-specific rates of VAD infection and subsequent outcomes. Methods: We analyzed IMACS adult patients with CF-LVADs from 2013-2017. We defined VAD infection using the ISHLT definitions as both VAD-specific infections including driveline, pump pocket/interior/exit cannula infection, and VAD-related infections including mediastinitis and VAD-related bloodstream infection. We compared the rates of VAD infections and post-infection events by flow type. Results: Patients with axial devices (N=9988) had both higher early (<=3 months) and late (>3 months) rates (per 100 patient-months) of developing VAD infections compared to those with centrifugal (N=5572; Early: 2.3 vs. 1.8, p<0.0001; Late: 1.5 vs. 1.4, p=0.04). Younger patients (18-40 years) with axial flow support were significantly less likely to be free from infection at 2 years compared to centrifugal flow, 64.8% vs. 76.1%, p<0.0001. Early-onset VAD infection in patients on support longer than 3 months was associated with higher post-3-to-6-month bleeding rates in both groups compared to uninfected patients (Axial: 19.8 vs. 3.2, p<0.0001; Centrifugal: 13.1 vs. 7.9, p<0.01) and a higher ischemic stroke rate in axial patients (1.81 vs. 0.93, p=0.01). Patients with early-onset VAD infection had a significant higher post-3-month mortality compared to un-infected patients (2-year survival: 64.1% vs. 77.1%, p<0.0001) yet similar post-infection mortality in axial and centrifugal (2-year survival: 64.6% vs. 63.0%, p=0.82). Furthermore, patients with early-onset VAD infection had a higher bleeding rate in axial compared to centrifugal (19.8 vs. 13.1, p<0.01). Conclusion: VAD infection rates were higher in axial devices both in the early and late time periods following device implant; younger patients had a higher hazard of VAD infection in this group. VAD infection was associated with higher bleeding and mortality in both flow type groups. Infection prevention programs specifically targeting VAD infections should be a key component of VAD research.