Predictors of long-term patency after femoropopliteal angioplasty: Resultsfrom the STAR Registry

PURPOSE: To identify variables predictive of long-term patency after femoro popliteal angioplasty. MATERIALS AND METHODS: The primary patency of 219 limbs in 205 patients fro m a multicenter registry who underwent femoropopliteal angioplasty between January 1, 1992, and December 31, 1994, was prospectively monitored with a combination of angiography, noninvasive hemodynamic testing, and clinical o utcome. Patient demographic, angiographic, and hemodynamic variables were e xamined alone and in combination to determine effect on long-term primary p atency. Each limb was graded as Category 1-4 according to the American Hear t Association (AHA) criteria for arterial lesions, and differences in outco me for each category were examined. Primary patency and intergroup analysis were determined with use of the Kaplan-Meter method and log-rank test, res pectively. Cox proportional hazards models were used to calculate relative risks for predictive variables. RESULTS: Primary patency rates for all limbs (on an intent-to-treat basis) at 12, 24, and 36 months were 87% +/- 3%, 80% +/- 3%, and 69% +/- 5%, respe ctively. Primary patency at 48 and 60 months was 55% +/- 7%. Poor tibial ru noff (single tibial vessel with 50%-99% stenosis or occlusion) was most pre dictive of occlusion (relative risk 8.5, P < .0001). The presence of diabet es or renal failure was associated with lower long-term patency (relative r isk 5.5 and 4.0, P < .0001 and .0002, respectively). Long-term patency was higher with AHA Category 1 lesions (P = .006), and no significant differenc e in patency was observed between Category 2 and 3 lesions (P = .65). A mul tivariate Cox proportional hazards model showed only the stratified runoff score and the presence of diabetes to be significant determinants of long-t erm patency. CONCLUSION: Poor tibial runoff is most predictive of lower long-term patenc y rates. Diabetes is also independently associated with lower long-term pat ency rates. The criteria that distinguish Category 2 and 3 lesions do not p redict differences in long-term patency, nor do they serve to identify lesi ons best treated with surgical bypass. This suggests that indications for f emoral angioplasty can be extended to include longer and more complex Categ ory 3 lesions.