Renal Artery Stenosis. Resident’s conference Presented by: Gagandeep K Heer, MD (PGY-2). Background.
Presented by: Gagandeep K Heer, MD
Major causes of the renal arterial lesions are:
Vasculitis (Takayasu’s arteritis)
Dissection of the renal artery.
Renal artery aneurysm
Renal artery coarctation
In 1964, Holley et al reported data from 295 consecutive autopsies performed in their institution during a 10-month period. The mean age at death was 61 years. In the whole group, the prevalence rate of RAS was 27% of 256 cases identified as having history of hypertension. 56% of these showed significant stenosis (>50% luminal narrowing). Among normotensive patients, the incidence of severe RAS was 17%. Among those older than 70 years, 62% had severe RAS.
Another study reported similar results, showing 18% incidence of severe RAS for patients aged 65-74 years and 42% for patients older than 75 years.
Dynamic gadolinium-enhanced magnetic resonance angiogram (MRA) shows normal renal arteries.
Digital subtraction flush aortogram in a 77-year-old normotensive man shows marked left renal artery stenosis and diffuse aortic atheroma. The patient presented with lower-limb claudication.
Flush aortogram in a 32-year-old man with familial hypercholesterolemia and difficult-to-control hypertension. Radiograph shows a complete occlusion of the right renal artery and marked stenosis of the left renal artery.
Gilfeather et al performed a study evaluating conventional angiography versus gadolinium-enhanced MRA in 54 patients and 107 kidneys. The study showed that in 70 kidneys (65%), the average degree of stenosis reported by readers of both modalities differed by 10% or less. In 22 cases (21%), MRA overestimated the degree of stenosis by more than 10% relative to the results of conventional angiography; in 15 cases (14%), MRA underestimated the stenosis by more than 10%.
Interventions appropriate for patients with RAS/RVHT may include
Left: A balloon angioplasty catheter is seen in situ across the left renal artery stenosis.