Patients with problematic proliferating IH underwent measurements of serum levels of plasma renin activity (PRA), ACE and angiotensin II (ATII) before, and 1–2 and 6 months following surgical excision, propranolol or captopril treatment.
This study included 27 patients undergoing surgical excision (n = 8), propranolol (n = 11) and captopril (n = 8) treatment. Treatment with either surgical excision or propranolol resulted in significant decrease in the mean levels of PRA. Surgical excision or captopril treatment led to significant decline in the mean levels of ATII. All three treatment modalities had no significant effect on the mean levels of ACE.
This study demonstrates the effect of surgical excision, propranolol and captopril treatment in lowering the levels of PRA and ATII, but not ACE, supporting a mechanistic role for the RAS in the biology of IH.