Health Human Disease Blog

This is most often an embolic phenomenon. Clot emboli originate in the heart in atrial fibril­lation or after myocardial infarction, or athero­matous emboli originate from the aorta after aortic manipulation during angiography or vascular sur­gery. Both types of embolization are obviously more prevalent in elderly patients.

Renal artery occlusion does not invariably cause renal infarction or symptoms. However, when symptoms occur, they usually reflect tissue ischemia and death. Sudden renal infarction may cause severe localized flank pain, nausea and vomiting, and oliguria, but rarely hematuria. A sudden onset or exacerbation of hypertension may occur. A leukocytosis may be seen along with elevations of lactate dehydrogenase (LDH) in serum and urine. Segmental or unilateral renal in­farction may be asymptomatic without an evident effect on renal function.

Renal vascular scintiradiography is a most use­ful initial test in suspected cases of renal infarc­tion. Total lack of renal blood flow in a dynamic study, or defects in activity on a static image, are highly compatible findings. Renal arteriography may be needed to visualize the extent or location of the occluding embolus/thrombus. Renal artery embolectomy has been successful in restoring blood flow and renal function even if performed two to four days after embolization.
Atheromatous embolization from an aortic plaque usually follows manipulation of an ath­erosclerotic aorta. The process presents as acute, oliguric renal failure following a surgical or an­giographic procedure of the aorta. Although ab­dominal aortic aneurysms rarely extend into the renal arteries, the manipulation required for sur­gical repair of the aneurysm may dislodge oc­cluding emboli. Asymptomatic atheromatous em­bolization to segmental arteries may occur spontaneously, as evidenced by local, healed renal infarcts discovered incidentally at autopsy.