Renovascular Disease Daniel Shoskes MD, MSc, FRCSC Professor of Surgery/Urology Glickman Urological and Kidney Institute Cleveland Clinic
Overview Pathophysiology Classification of Lesions Clinical Evaluation Medical and Surgical Management Renal Artery Aneurysm
Goldblatt Dog Models ARB/ACE inhibitors help Only help when Na depleted
Ischemic Nephropathy Does not correlate with hypertension Progressive azotemia in pt with risk factors for atherosclerotic disease Progresses through nephrosclerosis and atheroemboli Treatment of hypertension will not improve renal function, may actually exacerbate
Diameter and Blood Flow
Classification Atherosclerotic (70%) Fibromuscular Disease (30%)
Fibromuscular Disease Medial Fibroplasia: 77% Perimedial Fibroplasia: 10% Intimal Fibroplasia: 10% Fibromuscular Hyperplasia: 3%
Atherosclerosis typically a systemic disease involves proximal 2 cm of artery may only be seen on oblique views progression common, at least 50% in 2 years 10-15% progress to occlusion can cause hypertension and Renal Failure
Medial Fibroplasia most common fibrous women 25-50 commonly bilateral "string of beads" involves distal 2/3 and branches progression less common
Clinical Clues to RVH HTN onset < 30 yrs or > 55 sudden onset, short duration lack of family history difficult to control malignant crisis bruits disseminated atherosclerotic disease renal size disparity
Key Diagnostic Points Captopril provocation reduction of GFR detected by nuclear scan best predictor of surgical cure (spec 93-98%) increased PRA (off most drugs) Renal Vein Renins ipsilateral hypersecretion, contralateral suppression best for bilateral disease Ultrasound operator dependent, independent of renal function MRA poor images beyond main renal artery
Investigation of Ischemic Nephropathy High suspicion straight to angiography Mild to Moderate suspicion non-invasive imaging (local preference) if significant azotemia, US rather than MRA or spiral CT
Investigation of RVH High suspicion angiography and Renal Vein Renins if bilateral Moderate suspicion captopril nuclear renography (can do "post" study first) positive -> angio equivocal -> non-invasive imaging negative -> stop
Treatment of RVH Select medical management based on risk of ischemic nephropathy and lesion progression medial fibroplasia and atherosclerotic (without ischemic nephropathy) best for medical angioplasty +/- stents usually procedure of choice unless branch vessel disease renal artery aneurysm Nephrectomy if small and non-functioning
Treatment of Ischemic Nephropathy No benefit with unilateral disease Signs of reversibility progressive occlusion collaterals retrograde arterial filling size > 9 cm Cr < 4.0 preservation of glomeruli on biopsy
Surgical Approaches Hepatorenal Splenorenal Ileorenal Autotransplant Arteriotomy Aortorenal Thoracic aorta - renal
Renal Artery Aneurysms most small and asymptomatic pathology saccular (most common), fusiform, dissecting, intrarenal risk of rupture absent/incomplete calcification, >2cm diameter, expanding, hypertension, pregnancy other complications pain, hematuria, dissection, emboli