Utility of myocardial fractional flow reserve for prediction of restenosis following sirolimus-eluting stent implantation

Drug-eluting stents reduce restenosis due to neointimal growth suppression. Considering long-term outcomes, it is both difficult and important to predict drug-eluting stent restenosis. Thus, this study was designed to examine the utility of myocardial fractional flow reserve (FFR) as a predictor of sirolimus-eluting stent (SES) restenosis. Thirty-three patients (35 lesions) were enrolled. Upon completion of SES implantation, FFR was obtained under hyperemia. At 8 months of follow-up, coronary angiography revealed that five lesions had restenosis. Percent diameter stenosis (restenosis 68.7 +/- A 12.8% vs. non-restenosis 68.7 +/- A 12.4%, p = 0.78) and lesion length (restenosis 15.8 +/- A 9.4 mm vs. non-restenosis 14.4 +/- A 9.2 mm, p = 0.60) were similar. At post-intervention, percent diameter stenosis (restenosis 16.4 +/- A 6.1% vs. non-restenosis 14.0 +/- A 7.4%, p = 0.48) and minimum stent area (restenosis 6.01 +/- A 1.08 mm(2) vs. non-restenosis 6.27 +/- A 1.85 mm(2), p = 0.92) were also equivalent. However, proximal edge lumen area was smaller (restenosis 4.24 +/- A 1.40 mm(2) vs. non-restenosis 7.73 +/- A 2.64 mm(2), p = 0.004) and FFR was lower in the restenosis group (restenosis 0.81 +/- A 0.12 vs. non-restenosis 0.92 +/- A 0.06, p = 0.029). SES patients with restenosis had a lower FFR post stent deployment, suggesting the decreased FFR may be a useful predictor for SES restenosis.