[The role of iloprost in the treatment of critical ischemia of the limbs]

Abstract

Iloprost is a synthetic stable analogue of prostacyclin (PGI2), which shares its antiaggregating and vasodilating properties. Iloprost has been administered by i.v. route to patients with critical limb ischaemia (CLI) of different origin (maximal dosage: 2 ng/kg/min 6 hours/day infusion for 14-28 days). In patients with claudicatio intermittens (Fontaine stage II) iloprost improved the time to claudication and the maximal walking distance on treadmill, with an effect still lasting 60 days after suspension. This benefit was not related to a significant improvement in blood flow. Five multicentric, perspective, randomized versus placebo studies in patients with more severe CLI (Fontaine stage III-IV) susceptible to surgical treatment, showed that iloprost was able to reduce pain and ulcer dimensions. Furthermore, tha amputation rate of the ischemic limb was significantly lower in patients treated with iloprost during a 6 month follow-up (p < 0.01). Iloprost was also more effective than aspirin in causing pain relief and ulcer healing in patients with thromboangiitis obliterans and more effective than nifedipine in reducing frequency, intensity and duration of ischemic episodes in patients with Raynaud's phenomenon. Minor side effects of iloprost administration are represented by facial flushing, tachycardia, headache, nausea, vomiting, abdominal cramping, diarrhoea, whose frequency ranges from 16% to 70%; major collateral effects, occurring in less than 5% of patients, are above all represented by severe hypotension and angina pectoris. Clinical data indicate therefore that iloprost treatment can allow to improve the clinical conditions and the prognosis in patients with critical ischemia of the limbs, not candidate to surgical revascularization, by causing a relief of pain, a reduction in ulcer dimensions and deferring amputation.