Long-term survival of patients with critical limb ischemia treated with iloprost: response rate and predictive criteria. A retrospective analysis of 102 patients.

OBJECTIVE: Critical limb ischemia (CLI) patients have poor long-term prognosis. We showed that iloprost improves outcomes (major amputation and survival) up a 5year follow-up, but it is not known if in this length of time the survival curves, of clinical responders and non-responders, differ. PATIENTS AND METHODS: A retrospective study enrolling 102 consecutive patients between 2004-2008, with clinical and instrumental (ultrasound, angiography, transcutaneous tensiometry of oxygen TcpO₂ and carbon dioxide TcpCO2 in the affected and contralateral limbs) diagnosis of critical ischemia. All patients received the best medical therapy. Iloprost was administered (0.5-2 ng/kg/min 6 hours/day for 2-4 weeks) in all patients initially considered unsuitable for revascularization, repeating it regularly in time every six-twelve months in the case of positive response. The minimum expected follow-up was 4 years. RESULTS: 71.5% of patients were treated with iloprost and the responder rate was 71.2%. Most of the patients were regularly retreated with repeated cycles. Initial median supine TcpCO₂ in symptomatic limb was higher in untreated patients than those treated (58 vs. 49 mmHg; p < 0.05) and in non-responders compared to responders (60 vs. 49 mmHg; p < 0.05). TcpCO2 directly and significantly correlated with the highest risk of mortality and seems to represent a new accurate prognostic criterion of unfavourable short and long-term response to prostanoid. In iloprost group, major amputations were significantly reduced. Revascularization was significantly higher in non-responders (57.1% vs. 11.5%; p < 0.05). There was a significantly higher prevalence of subsequent myocardial infarction in the non-iloprost group (27.6% vs. 9.6%; p < 0.05). The survival rate of non-responders was higher than untreated up until the second year (76.2% vs. 62%; p < 0.05). At 4 years we found higher survival in patients treated with iloprost (64.3% vs. 41% in untreated; p < 0.05) and in responders (75% vs. 38.1% in non-responders; p < 0.05). CONCLUSIONS: Our results confirm the favourable role of iloprost on the long-term outcome in patients with CLI. In particular, the maximum benefit is obtained in responder patients treated with multiple cycles of infusion. [ABSTRACT FROM AUTHOR]