A confidence profile analysis of the results of femoropopliteal percutaneous transluminal angioplasty in the treatment of lower-extremity ischemia

Abstract

The many reports on the use of percutaneous transluminal angioplasty (PTA) for treating lower-extremity ischemia were analyzed to determine the outcomes of femoropopliteal PTA used in patients with intermittent claudication (IC) and with more severe limb-threatening ischemia ("salvage"). The Confidence Profile Method was used to interpret and adjust the evidence from 12 selected clinical reports, and to combine the data into single best estimates of the outcomes that were considered important for decision making. The following combined estimates were obtained: The early success rate was 89% +/- 2.5% after PTA for IC, compared with 77% +/- 4% after PTA for salvage. The largest decline in patency occurred during the first 6 to 12 months. After 2 years there was little further attrition. Three-year patency was 62% +/- 9% for IC and 43% +/- 7% for salvage. The risk of procedure-related mortality and limb loss was low, estimated at 0.5% and 1%, respectively. The risk of serious complications requiring surgical repair was about 2.5%. The Confidence Profile Method is a novel way of obtaining this information from the imperfect clinical literature. The method incorporates subjective judgments and assumptions and gives quantitative and visual representations of both the magnitude of the estimated outcome and the uncertainty associated with it. The results are as strong as the assumptions incorporated in them are valid. The estimates derived in this study can be used for any decision on the use of PTA in the femoropopliteal segment.