[Hypertension].

This 40 year old man had been treated adequately for arterial hypertension over the last 10 years. Within one year this arterial tension rose continuously in spite of treatment. A low blood-potassium value found on routine chemical analysis prompted an investigation on secondary causes for hypertension. The results of a peripheral renin-study were typical for secondary aldosteronism. An abdominal aortography and selective angiography of the renal arteries visualized an intrarenal arterial aneurysm with stenoses as causative factor of the renovascular hypertension. Antihypertensive treatment with an ACE-blocker permitted to normalize the blood-pressure values subsequently.