Fibromuscular hyperplasia: extension of the disease and therapeutic outcome. Results of the University Hospital Zurich Cooperative Study on Fibromuscular Hyperplasia.

92 patients with fibromuscular hyperplasia (FMH) seen at the University Hospital Zurich were studied. Renovascular FMH was the most frequent manifestation of the disease (89%). FMH of the cerebral arteries was seen in 26%. The intestinal and subclavian arteries were involved in 9% each and the iliac arteries in 5% of the patients. In 2 patients each FMH of the abdominal aorta or the coronary arteries, respectively, was found. 26% of the patients had systemic disease with involvement of 2 or more arteries. Half of the patients with bilateral renovascular disease showed additional extrarenal FMH. All patients with renovascular FMH were hypertensive (mean blood pressure 194 +/- 34/119 +/- 18 mm Hg). Surgery, percutaneous transluminal angioplasty (PTA) and medical therapy were equally effective in controlling blood pressure. The cure rates were 52% in patients undergoing surgery and 50% in those treated with PTA. The complication rate, however, was higher with surgery (11%) than with PTA (3%). 62% of the patients treated medically were normotensive. Major side effects occurred in 4.8%. The outcome of curative interventions (surgery or PTA) was influenced by the extension of FMH. In unilateral disease the cure rate was significantly higher (62%) than in systemic FMH (28%; p less than 0.03). Patients with strict bilateral disease were cured in 50%. We conclude: (a) PTA seems to be the treatment of choice in renovascular FMH because of a high cure and a low complication rate and (b) the outcome of curative interventions seems markedly influenced by the extension of FMH in these patients.