Exclusion Criteria: pain at rest, trophic ulcers or gangrene (critical limb ischemia), if they were unable to cooperate, or one of the following conditions (contraindications or precautions for use of iloprost) was present: myocardial infarction or stroke in the previous 6 months; congestive heart failure NYHA class >II; unstable angina; uncontrolled severe arterial hypertension (systolic BP >180 mmHg or diastolic BP >110 mmHg) or hypotension (systolic BP <90 mmHg); hyperkinetic ventricular arrhythmia; acute pulmonary edema or pulmonary congestion; bleeding diathesis; platelet count <80,000 or > 500,000/mm3; renal failure requiring dialysis; liver cirrhosis; pregnancy or breast feeding; history of allergy, hypersensitivity or intolerance to iloprost or other prostanoids.