From anatomy to function: diagnosis of atherosclerotic renal artery stenosis

Atherosclerotic renal artery stenosis (ARAS) affects 7% of the over 65 s and will be increasingly common with an ageing population. ARAS obstructs normal renal perfusion with adverse renal and cardiovascular consequences. Drug therapy is directed at reducing atherosclerotic risk. Two recent major trials of revascularization for ARAS showed that clinical outcomes were not improved beyond those offered by optimal drug therapy in most patients. This reflects experimental data showing that restoration of blood flow alone may not attenuate a cascade of tissue injury. A shift from anatomic to functional imaging of ARAS coupled to novel therapies might improve clinical outcomes in selected patients. This review outlines the case for separately assessing hemodynamic significance of arterial stenosis and functional reserve of renal parenchymal tissue. The authors consider current and emerging diagnostic techniques for ARAS and their potential to allow individualized and functionally directed treatments.