RFRIST Study (Fractional Flow Reserve in Functional Quantification of Renal Allograft Artery Stenosis): Rationale and Study Design

ABSTRACT Background Renal allograft artery stenosis is the most prevalent vascular complication after renal transplantation. The diagnostic limitations of noninvasive tests are well defined and angiography remains the gold standard for diagnosis and therapeutic definition. The use of fractional flow reserve for a better stratification of native renal artery stenosis may be useful for an adequate selection of patients for percutaneous treatment, however this method has not yet been validated in patients undergoing transplantation. The objective of this study is to describe and standardize the fractional flow reserve protocol in patients with renal allograft artery stenosis in a group of patients selected for percutaneous renal intervention, correlating the method with angiography Methods Cross-sectional, single center pilot study (Hospital Sao Paulo/ Universidade Federal de Sao Paulo, Sao Paulo, SP, Brazil), including 10 patients with a clinical picture compatible with renal allograft artery stenosis, with angiography showing graft stenosis > 60% and admitted for percutaneous renal intervention. Graft dysfunction assessment will include biomarkers of renal function. Conclusions In this study, a fractional flow reserve protocol for the functional assessment of renal allograft artery stenosis will be standardized, evaluating an alternative method capable of identifying patients most likely to benefit from percutaneous renal intervention.