Tricuspid Regurgitation and Kidney Transplant Recipient Outcomes

Abstract

Rationale & objectiveKidney function can be adversely affected by significant tricuspid regurgitation (TR) due to effects on cardiac output and systemic venous congestion. However, the impact of significant TR on short- and long-term kidney function following a kidney transplant remains uncertain. Study designRetrospective observational cohort. Setting& participants: Kidney transplant recipients from a from a single center between 2016 and 2019, ExposureSignificant TR, defined by at least moderate regurgitation, on echocardiogram prior to kidney transplantation. OutcomesPrimary endpoints included estimated glomerular filtration rate (eGFR) at three time points: two weeks, three months, and one year after transplantation. Secondary endpoints included major adverse cardiac events (MACE) including non-fatal myocardial infarction, all-cause mortality, and hospitalization due to cardiovascular disease. Analytical approachPropensity score matching was performed in a 1:3 ratio between patients treated with significant TR and controls, within a caliper 0.05 SD of the propensity score, to analyze for the primary endpoint. ResultsAmong 557 kidney transplant recipients, 26 (5%) exhibited significant TR pre-transplantation. According to propensity score matching analysis, with 1:3 ratio between 24 patients with significant TR and 72 controls, the presence of significant TR was associated with lower eGFR post-transplantation. Specifically, the mean eGFR was 41.2 mL/min/1.73 m2 compared to 53.3 mL/min/1.73 m2 at 2 weeks (P < 0.01), 50.0 mL/min/1.73 m2 versus 60.3 mL/min/1.73 m2 at 3 months (P < 0.01), and 49.4 mL/min/1.73 m2 versus 61.2 mL/min/1.73 m2 at one year (P < 0.01).Delayed graft function was observed in 41.7% of the patients with significant TR compared to 12.5% of those without significant TR (P<0.01). No patients with significant TR required dialysis after one year. One-year MACE was non-significantly higher among patients with significant TR (20.8% vs 8.1%; P=0.16). LimitationsRetrospective design and relatively small TR population. ConclusionsThe presence of significant TR among kidney transplant recipients was associated with lower eGFR at two weeks, three months and one year following transplant, although all remained dialysis independent at 1 year.