ACE Inhibitors May Prevent Rupture of Abdominal

Aortic Aneurysms

A review of data on hospitalized patients revealed that ACE inhibitors, but not other antihypertensives, were associated with lower risk for rupture.

No known medical treatment prevents rupture of an abdominal aortic aneurysm (AAA). However, animal studies have suggested that the renin–angiotensin system may contribute to the development of aneurysms and that angiotensin-converting–enzyme (ACE) inhibitors, but not other antihypertensive drugs, may delay their expansion and rupture. To test this hypothesis in humans, Canadian investigators compared 3379 patients hospitalized for ruptured AAAs and 11,947 patients hospitalized for unruptured AAAs between 1992 and 2002. The two groups were similar in demographics and health status.

Patients who had received an ACE inhibitor in the 3 months prior to admission had a significantly smaller likelihood of aortic rupture than patients who had not received an ACE inhibitor (odds ratio, 0.82). After adjustment for potential confounders, findings were similar for each of the three ACE inhibitors used most often (enalapril, lisinopril, and ramipril) and for both high and low doses of these agents, but not in patients who had stopped taking their ACE inhibitor before being hospitalized. No other class of medication, antihypertensive or otherwise, was associated with a reduced risk for rupture.

Comment: This case-control study will not immediately change clinical practice (except perhaps in patients with abdominal aortic aneurysms who have no surgical options), but it should provoke randomized studies to further assess the value of ACE inhibitors in patients with AAAs.

— Bruce Soloway, MD

Published in Journal Watch September 26, 2006

Citation(s):

Hackam DG et al. Angiotensin-converting enzyme inhibitors and aortic rupture: A population-based case-control study. Lancet 2006 Aug 19; 368:659-65.