Long-term Clinical and Angiographic Follow-up of the New Non-Polymeric Paclitaxel-Eluting Stent for the Treatment of De Novo Coronary Lesions: Outcomes of the PAX-B Study

Background Compared with the Taxus® stent, the non-polymeric paclitaxel-eluting Amazonia® PAX stent shows no differences in the occurrence of coronary restenosis or clinical events after four months of follow-up. However, the performance of the Amazonia® PAX stent in more complex cases and with longer angiographic follow-up has not been demonstrated. Methods The PAX-B study was a prospective, non-randomised, multicentre study assessing the long-term follow-up of patients treated with the Amazonia® PAX stent. The primary outcome was late in-stent lumen loss. Results The study included 103 patients with a mean age of 61.3 ± 11.4 years; 26.2% were diabetics, 24.3% had acute coronary syndromes, and 71.6% had type B2/C lesions. Multiple stents were implanted in 4.7% of the patients, and angiographic success was achieved in 100% of the cases. During hospitalisation, the periprocedural acute myocardial infarction rate was 3.9%, and one of these events led to target-lesion revascularisation (TLR). At the nine-month angiographic follow-up, the median late in-stent lumen loss was 0.91 [0.50; 1.21] mm. The cumulative rates of major adverse cardiac events at the six-month, nine-month, and 12-month follow-ups were 7.8%, 18.5%, and 21.3%, respectively, mostly due to TLR. There were no deaths or stent thromboses at 12 months. Conclusions The Amazonia® PAX stent showed excellent immediate results and a good safety profile. However, angiographic recurrence rates were relatively high because of the low efficacy of neointimal hyperplasia inhibition.