Renal Artery Stenosis: Epidemiology, Clinical Manifestation, and Percutaneous Endovascular Therapy

Abstract

Renal artery stenosis may cause or deteriorate arterial hypertension and/or renal insufficiency. Technical improvements of diagnostic and interventional endovascular tools have lead to a more widespread use of endoluminal renal artery revascularization and extension of the indications for this type of therapy. Since the first renal artery angioplasties performed by Felix Mahler and Andreas Grüntzig in 1978, numerous single-center studies have reported the beneficial effect of percutaneous transluminal renal angioplasty, and since the early 1990's stenting of renal artery stenosis caused either by atherosclerosis or by fibromuscular dysplasia. This article summarizes the impact of technical improvements of endovascular tools on interventional techniques during the last decade and gives an overview concerning the clinical impact of renal artery revascularization. Despite the absence of sufficient randomized studies, there is nonetheless evidence that stenting of hemodynamically relevant atherosclerotic renal artery stenosis has an impact on blood pressure control, renal function, and left ventricular hypertrophy.

Renal Resistive Index

“…However, RI does not predict outcomes after renal revascularization despite initial, promising results. 19 Although compliance of intrarenal arteries influences RI, changes in these vessels often reflect a similar process throughout the systemic vasculature that can be the result of altered central hemodynamics associated with aging. 13,20 Thus, differentiating the role of renovascular factors from the role of systemic vascular factors in the prognostic information provided by renal RI can be problematic.…”

Determinants and Prognostic Significance of the Renal Resistive Index

“…Several previous studies demonstrated that a side-to-side difference in RRI of at least 0.05 is a specific marker of severe unilateral renal artery stenosis [35]. However, because of the major influence of the systemic hemodynamic factors and renal vascular compliance on the intrarenal arterial waveforms, the RRI could not serve as a specific marker reflecting exclusively renal artery resistance or renal pathology.…”

Imaging Modalities for Renal Artery Stenosis in Suspected Renovascular Hypertension: Prospective Intraindividual Comparison of Color Doppler US, CT Angiography, GD-Enhanced MR Angiography, and Digital Substraction Angiography

“…However, conventional angiography still has superior resolution for the evaluation of small vessels and offers the option of simultaneous therapeutic interventions such as percutaneous revascularization by balloon angioplasty and/or stenting. [11] Surgical intervention is often reserved for selected cases based mainly on the mapping of findings of the renal arteries.…”

“…[11] The aim of the present study is to compare these four imaging methods in a patient cohort suffering from hypertension attributed to renovascular etiology and suggest an imaging algorithm according to the imaging findings.…”