Factors that determine the long-term results of percutaneous transluminal dilatation for peripheral arterial occlusive disease.

Seven hundred thirty-one percutaneous transluminal dilatations (TLDs) for peripheral arterial occlusive disease were performed between 1978 and 1984. From this prospective study 666 dilatations were analyzed with a combination of clinical and objective vascular laboratory tests to determine which factors could be used to predict long-term successful results. Eleven variables were recorded at the time of TLD. The proportional hazards model (Cox regression) identified four significant variables predictive of long-term success: the indication for the procedure (claudication or salvage), site of the dilatation (aortoiliac or femoropopliteal), runoff (poor or good), and whether a previous TLD was done at the same site. With these significant variables, the Cox model was used to estimate the chances of success at 1, 2, and 3 years for all combinations of variables. The accuracy of the Cox model was confirmed by the close approximation between the number of observed and predicted successful TLDs at 1, 2, and 3 years. We concluded that the chances of success of TLD in terms of percentage at 1, 2, and 3 years can be predicted from the combinations of these four significant variables. Knowledge of these factors should permit better selection of patients for this procedure.