Beneficial Effect of a New Prostacyclin Derivative on the Walking Capacity in Patients with Peripheral Arterial Insufficiency

The efficacy, tolerance and safety of iloprost, a stable analogue of carbaprostacyclin, were evaluated in 7 patients with peripheral arterial insufficiency at stage II of Fontaine's classification. After washout, placebo was infused intravenously for seven days, then iloprost was given by a six-hour intravenous infusion of 1 ng/kg/min over the next seven days. At the end of each period, the initial (ICD) and the absolute (ACD) claudication distance were measured by treadmill. The ankle/arm systolic blood pressure ratio (WI) was also assessed, at rest and ten minutes after exercise. As compared with placebo, ICD increased from 98 +/- 60 to 137 +/- 91 meters (p less than 0.05) and ACD from 151 +/- 76 to 210 +/- 95 meters (p less than 0.05). Similarly, WI rose from 0.44 +/- 0.14 to 0.52 +/- 0.18 (p less than 0.05) at rest and from 0.40 +/- 0.13 to 0.48 +/- 0.20 (p less than 0.05) ten minutes after treadmill exercise. Owing to the spontaneous fluctuation in walking distance experienced by such patients, an increase in ACD greater than or equal to 50% was considered as clinically relevant. In 3 patients, who experienced such an improvement, iloprost continued to be infused at the same dosage as before, for an additional seven days. In the remaining 4 patients (nonresponders), the dose was increased to 2 ng/kg/min.(ABSTRACT TRUNCATED AT 250 WORDS)