Aims: In contrast to the cytostatic and cytotoxic pharmacotherapy of drug eluting stents, approaches to stimulate the arterial healing response by accelerating re-endothelialisation may be an attractive alternative to prevent post-stenting neointimal formation and thrombosis. The study sought to evaluate whether stainless steel stents able to sequester endothelial progenitor cells (EPCs) to the stent surface to promote the endogenous arterial healing, can prevent in-stent restenosis and stent thrombosis.
Methods and results: The HEALING-II study was a multicentre, prospective registry study, including 63 patients treated with the implantation of a Genous EPC capture stent. The primary safety endpoint was Major Adverse Cardiac Events (MACE) at 30 days, whereas the primary efficacy endpoint was percent in-stent volume obstruction at 6 months by intravascular ultrasound (IVUS). The 9 month composite MACE rate was 7.9%, whereas 6.3% clinically justified target lesion revascularisations were observed. Although patients received one month of clopidogrel, no angiographic stent thrombosis occurred. In-stent late luminal loss was 0.78+/-0.39 mm and percent in-stent volume obstruction was 22.9+/-13.7% (mean+/-sd). Patients with normal EPC titers at 6 months FU responded favourably to the EPC capturing stent (late luminal loss 0.53+/-0.06) as opposed to patients with low EPC titers (late luminal loss 1.01+/-0.07). These low circulating EPC titers were generally associated with the lack of HMG-Co-A reductase inhibitors ('statins') at the time of stent implantation and diabetes mellitus.
Conclusions: The HEALING-II study suggests that the EPC capture coronary stents are safe and effective for the treatment of de novo coronary artery disease in patients with normal EPC levels.