Approximately a third of patients with peripheral arterial disease (PAD) will develop intermittent claudication.  A previous pilot trial found that the angiotensin-converting enzyme inhibitor ramipril is associated with increased pain-free and maximum walking times, contrasting with previous ACE inhibitor studies which may have been limited by issues of small sample size, short intervention duration, and lack of a placebo group.  Therefore this trial was designed to investigate the effect of 24 weeks of ramipril therapy on walking distance and health-related quality of life as compared with placebo in a larger, more general PAD population including patients with diabetes and patients with aortoiliac and infrainguinal disease.

212 patients with peripheral arterial disease were recruited from three Australian hospitals, and randomised to receive 10mg of ramipril daily, or placebo, for 24 weeks.  Maximum and pain-free walking times were recorded during a standard treadmill test.  The Walking Impairment Questionnaire (WIQ) and Short-Form 36 Health Survey (SF-36) were used to assess walking ability and quality of life, respectively.

At six months, patients taking ramipril had a 75-second increase in pain-free walking time compared to those taking placebo (P<.001), and a 255-second increase in maximum walking time (P<.001).  WIQ and SF-36 scores also improved, although ramipril did not affect the overall SF-36 median Mental Component Summary score.

Conclusions:

In patients with intermittent claudication, 24-week treatment with ramipril led to significant improvements in pain-free and maximum treadmill walking times, which was also associated with an increase in the physical functioning component of the SF-36 score.

• Effect of Ramipril on Walking Times and Quality of Life Among Patients With Peripheral Arterial Disease and Intermittent Claudication.  JAMA 2013;309:453-460.