Renal artery aneurysms. Significance of macroaneurysms exclusive of dissections and fibrodysplastic mural dilations.

Seventy-two patients (39 females and 33 males), 9 to 84 years in age, exhibited a total of 94 renal artery macroaneurysms. Solitary aneurysms affected 53 patients, and multiple aneurysms occurred in 19 patients. Arteriosclerotic changes, observed in nearly 30% of aneurysms, were considered secondary rather than primary processes in most instances. Renal artery fibrodysplasia was an associated finding among 27 patients. In 57 hypertensive patients, evidence supportive of renal artery aneurysms contributing to elevated blood pressure was meager. Two patients experienced frank aneurysmal rupture. Covert rupture into renal veins occurred twice. Aneurysmectomy was performed on 31 occasions. Nephrectomy, partial as well as total, was performed 17 times. No operative mortality occurred. Potential for rupture and an association with functionally important renal artery stenoses support surgical intervention in selected patients with renal artery macroaneurysms.