Is Restenosis/Reocclusion after Femoropopliteal Percutaneous Transluminal Angioplasty (PTA) the Consequence of Reduced Blood Flow, Inflammation, and/or Hemostasis Disturbances?

Percutaneous transluminal angioplasty (PTA) is an established method for treat‐ ment of peripheral artery disease (PAD) of the femoropopliteal artery. However, in up to 50% of patients restenosis and/or reocclusion remain a frequent complication occurring in the first year after the procedure. In this study, we focused on the influ‐ ence of compromised postprocedural infrapopliteal runoff of the affected limb, on the hypercoagulability as detected by a global hemostasis assay and on genetic pre‐ disposition to hypercoagulability and on the regulation of the inflammation through the nuclear receptor related 1 protein (NuRR1). Consecutive PAD patients treated by femoropopliteal PTA because of disabling claudication or critical limb is‐ chemia were followed up by vascular ultrasound imaging at 1, 6, and 12 months af‐ ter the procedure. Venous blood samples for hemostasis, inflammation, and gene analysis were obtained before and 24 h after PTA. One month after femoropopliteal PTA, 23% of patients with compromised runoff developed the combined end point restenosis/reocclusion in comparison to 11% with good runoff (p = 0.03). After 6 months, the differences were no longer significant. It was concluded that compro‐ mised postprocedural infrapopliteal runoff predisposes to early restenosis/reocclu‐ sion after femoropopliteal PTA and that the deterioration of infrapopliteal runoff in the year after femoropopliteal PTA is accompanied by worsening of long-term fem‐ oropopliteal patency. Patients were genotyped for the prothrombotic gene polymor‐ phisms: platelet receptor glycoprotein IIIa T1565C, coagulation factor V G1691A, coagulation factor II G20210A, coagulation factor XII C(-4)T, and plasminogen acti‐ vator inhibitor-1 4G5G. We were not able to show any association between these polymorphisms and the restenosis/reocclusion rate in patients treated with femoro‐ popliteal PTA. Furthermore, no association between thrombin generation and reste‐ © 2015 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. nosis/reocclusion rate was established. NuRR1 haplotypes significantly increased the restenosis/reocclusion rate after PTA (adjusted relative risks were 1.6, 95% CI 1.1–2.3 for haplotype 2 and 2.0, 95% CI 1.3–2.8 for haplotype 3). To conclude, this study suggested a significantly higher restenosis/reocclusion rate in patients with compromised runoff compared to patients with a good runoff 1 month after the procedure. Hypercoagulability was not associated with the restenosis/reocclusion rate, and the prothrombotic polymorphisms were equally distributed among pa‐ tient with and without restenosis/reocclusion, suggesting minor or no role in reste‐ nosis/reocclusion. Haplotypes 2 and 3 in the NuRR1 gene significantly increased the restenosis/reocclusion rate, suggesting significant role of inflammation. In this on‐ going study, further analysis on a larger group of patients is warranted.