Significant Increase in 1-Year Posttransplant Renal Arterial Index Predicts Graft Loss

Abstract

Background and objectives: Conflicting data have been reported concerning the use of kidney graft arterial resistance index (RI) measured by Doppler to predict death-censored graft loss. We hypothesized that changes in RI values could carry better information than a single measure of RI.Design, setting, participants, & measurements: Four hundred twenty-five renal transplant recipients were included in the study. We tested whether changes in renal arterial resistance index between 4 and 12 months after transplant (⌬RI 4312 ) were predictive of graft loss.Results: Neither 4-month nor 1-year RI predicted graft loss. The area under the receiver operating characteristics curve of ⌬RI 4312 for graft loss was 0.75. A ⌬RI 4312 >10% had the best sensitivity and specificity. One year after transplant, 22% of the study population had ⌬RI 4312 >10%. Fifty-five patients (12.9%) experienced graft loss during follow-up. The annual incidence of graft loss was higher in patients with ⌬RI 4312 >10% (3.5 versus 1.3%; P ‫؍‬ 0.009). In multivariate analysis, patients with ⌬RI 4312 >10% had an increased risk of graft loss (hazard ratio, 6.21; 95% confidence interval, 1.99 to 22.15; P ‫؍‬ 0.002).Conclusions: A variation in RI >10% in the first year after transplant is an independent risk factor for death-censored graft loss in renal transplant recipients.

The Role of the Intrarenal Resistive Index in Kidney Transplantation

“…They observe that a resistive index of 0.80 or higher is associated with patient mortality but not with renalallograft histologic features or kidney function as measured by either a decrease in the estimated GFR of 50% or more or the need for dialysis. Their findings differ from those of most previous studies, [1][2][3][4][5] in which an increased resistive index was associated with organ deterioration. What could be the possible reasons for this discrepancy?…”

“…[1][2][3][4][5] It was initially thought that the intrarenal resistive index was solely dependent on vascular resistance. However, renal vascular compliance also contributes to the resistive index.…”

The Renal Arterial Resistive Index and Stage of Chronic Kidney Disease in Patients with Renal Allograft

“…However, several studies reported contradictory results. Loock et al reported that neither 4-month nor 1-year renal arterial resistive index predicted loss of kidney allografts [6]. The study by Gerhart et al did not confirm that a renal arterial resistive index higher than 0.80 may predict event-free transplant survival [7].…”

Relation of Resistive and Pulsatility Indices With Graft Function After Renal Transplant

“…8,9 However, there are conflicting data regarding the reliability of some indices, such as the resistive and the pulsatility indices in renal transplant recipients by this technique. [9][10][11][12][13] The present study was designed and conducted to evaluate the association between the value of these indices during the first week after transplant and 3-month outcomes in renal transplant recipients.…”