Kidney Week

Abstract: FR-OR94

Kidney Function Trajectories, Risk Factors, and Outcomes in Left Ventricular Assist Device (LVAD) Recipients

Session Information

• Novel Clinical Impacts on Cardiorenal Disease
  November 03, 2023 | Location: Room 103, Pennsylvania Convention Center
  Abstract Time: 04:57 PM - 05:06 PM

Category: Hypertension and CVD

• 1602 Hypertension and CVD: Clinical

Authors

• Walther, Carl P., Baylor College of Medicine, Houston, Texas, United States

Carl P. Walther, MD, MS, FASN

• Mondal, Nandan, Baylor College of Medicine, Houston, Texas, United States

Nandan Mondal,

• Navaneethan, Sankar D., Baylor College of Medicine, Houston, Texas, United States

Sankar D. Navaneethan,

Background

LVAD (Left ventricular assist device) implantation can improve or worsen kidney function due to several known and hypothesized causes. However, competing risks of death and transplantation, patterns of missing data, and inaccuracy of estimating equations complicate kidney outcome assessment. To enable additional insight into the effects of LVAD implantation on kidney health, we investigate use of a continuous metric (trajectory of log eGFR) to summarize long-term post-LVAD kidney health.

Methods

We identified adults who received isolated primary continuous-flow LVADs from 2012 to 2017 in a US national database of LVAD recipients (INTERMACS). We assessed eGFR-Cr (CKD-EPI 2021) from pre-LVAD implantation to 12 months, fitting linear mixed models with random slopes and intercepts to natural log-transformed eGFR values (so that slopes would approximate proportional changes), adjusted for baseline eGFR. We then investigated how baseline factors related to worse than average kidney function trajectory and how kidney function trajectory related to mortality risk.

Results

We identified 15,052 LVAD recipients (median age 59 years, 21.2% female, median pre-LVAD eGFR 62 ml/min/1.73m²). The median eGFR trajectory slope was approximately -5.6% over one year; only 23.3% had a positive trajectory slope. The ten baseline factors most associated with worse than average kidney function trajectory are shown in Figure 1A: ‘older age’ was the most significant risk factor; ‘no prior cardiac operation’ was the most significant protective factor. In addition, mortality was progressively higher with worse kidney function trajectory (Figure 1B).

Conclusion

A log eGFR trajectory measure over one year may be a useful summary outcome metric in investigating the effects of LVADs on kidney health/function. As a continuous summary metric, this may provide improved power to study determinants of kidney outcomes in LVAD recipients. In addition, as a log trajectory measure, it may be less susceptible to the imprecision and non-kidney-related confounding inherent in estimating GFR.

Funding

• NIDDK Support