Prediction of Chronic Limb Threatening Ischemia by Clinical Data: The PREDICCMI Study

Abstract

Background

The main objective was to develop a clinical model to predict critical lower limb ischemia (CLI). Secondary objectives were to assess the reproducibility of clinical data and to create a predictive score for major amputation.

Methods

Prediction de l'ischémie critique des membres inférieurs was a French multicenter prospective observational study that included patients suspected of chronic limb threatening ischemia (CLTI). The first end point was hemodynamic confirmation of CLI according to the European consensus and Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC) II definitions. We created models from clinical data to predict CLTI and major amputation or vascular death at 1 year based on CLI classifications and clinical and hemodynamic data.

Results

Five hundred seventy-four patients were included. After a median follow-up of 22.3 months (Q1-Q3 10.8–34.7), 243 patients (42%) had died and 96 patients (16%) had undergone at least one major amputation. The clinical model poorly predicted objectively confirmed CLI (c index 0.610 [0.560–0.630]). However, a combination of clinical data and systolic toe pressure predicted the risk of major amputation (area under the curve 0.710 [0.647–0.760]).

Conclusion

Classical classifications of CLI are not adequately predicted by clinical parameters. While purely clinical models also poorly predict vascular outcome, a model including clinical data and systolic toe pressure seems to predict major amputation or vascular death satisfactory.