Elevated whole-blood tissue factor procoagulant activity as a marker of restenosis after percutaneous transluminal coronary angioplasty and stent implantation.

BACKGROUND: Experimental data suggest that tissue factor (TF) may induce neointimal hyperplasia after arterial injury. In this study, we investigated the hypothesis that elevated levels of TF in the circulation contribute to the development of restenosis after percutaneous transluminal coronary angioplasty (PTCA) or stent implantation.

METHODS AND RESULTS: Whole-blood TF procoagulant activity (TF-PCA) was measured using a previously described assay before, at 3 hours after, and at 24 hours after the intervention in 61 patients with stable angina undergoing PTCA (n=20) or stent implantation (n=41). Coronary angiography was performed 4 to 6 months after the intervention, and luminal narrowing > or =50% was defined as restenosis. Whole-blood TF-PCA levels did not correlate with intracellular monocyte tumor necrosis factor-alpha expression, a marker of activation of these cells. Baseline levels and time course of whole-blood TF-PCA after the intervention were compared in patients who did or did not subsequently develop restenosis. Whole-blood TF-PCA levels did not change significantly in the 24 hours after either intervention. However, in both the PTCA and stent groups, initial TF-PCA was significantly higher in patients who subsequently developed restenosis (P=0.018 and 0.039 compared with those who did not develop restenosis for PTCA and stent groups, respectively).

CONCLUSIONS: Higher baseline values of whole-blood TF-PCA may be a predictor of restenosis after PTCA and stent implantation.