Increase of Walking Capacity After Acute Aminophylline Administration in Intermittent Claudication

Abstract

In the presence of peripheral atherosclerotic disease, inappropriate adeno sine release during exercise might promote excessive arteriolar dilation leading to steal phenomena and ischemia.

In order to test this hypothesis, IV aminophylline (6 mg/kg over fifteen min utes), a dosage known to effectively block adenosine receptors, was acutely ad ministered—in a double-blind, placebo-controlled study design—in 13 patients with intermittent claudication and documented atherosclerotic disease. All pa tients performed two treadmill exercise tests at the same hour on two consecu tive days, five minutes after aminophylline or placebo administration randomly allocated. Pain-free time was 109±133 (mean±SD) seconds after placebo and 173±165 seconds after aminophylline (p < .01); maximum time to claudication was 273±191 seconds after placebo and 397±318 seconds after aminophylline (p < .05).

The authors conclude that intravenous aminophylline markedly increases the walking capacity in patients with intermittent claudication, possibly by pre venting flow maldistribution phenomena through adenosine receptors block ade.