ACE-inhibitor related angioedema

The pathophysiology of angiotensin-converting enzyme inhibitor (ACEi)–induced angioedema most likely resembles that of hereditary angioedema, ie, it is mainly mediated by bradykinin-induced activation of vascular bradykinin B2 receptors. It was hypothesised that the bradykinin B2 receptor antagonist icatibant might therefore be an effective therapy for ACEi-induced angioedema. This month’s Annals of Emergency Medicine reports research assessing its effciacy in a small series of patients, with a retrospective comparison against steroid and antihistamine therapy.

The eight patients with acute ACEi-induced angioedema were treated with a single subcutaneous injection of icatibant. First symptom improvement after icatibant injection occurred at a mean time of 50.6 minutes and complete relief of symptoms at 4.4 hours. In the historical comparison group treated with methylprednisolone and clemastine (an antihistamine / anticholinergic), the mean time to complete relief of symptoms was 33 hours. Some of these patients received a tracheotomy (3/47), were intubated (2/47), or received a second dose of methylprednisolone (12/47).

Therapeutic Efficacy of Icatibant in Angioedema Induced by Angiotensin-Converting Enzyme Inhibitors: A Case Series
Ann Emerg Med. 2010;56(3):278-82