Novel, vessel anatomy adjusting drug-coated balloon-Preclinical evaluation in peripheral porcine arteries.

Abstract

The diameter of balloons or stents is selected according to the estimated reference vessel diameter and do not adapt to the vessel anatomy. The aim of the present preclinical studies was to investigate a novel, vessel anatomy adjusting hypercompliant drug-coated balloon catheter (HCDCB). Hypercompliant balloon membranes were coated in a constricted state with high drug density. Drug adherence was investigated in vitro, transfer to the porcine peripheral arteries and longitudinal distribution in vivo. In young domestic swine, neointimal proliferation was induced by vessel overstretch and continuous irritation by permanent stents. Uncoated hypercompliant balloons (HCB), and standard uncoated balloons and drug-coated balloons (DCB) served as controls. Efficacy was assessed by angiography, optical coherence tomography (OCT), and histomorphometry. HCDCB lost 18.0 ± 3.9% of dose during in vitro simulated delivery to the lesion. Drug transfer to the vessel wall was 13.9 ± 6.4% and drug concentration was 1,044 ± 529 ng/mg tissue. Four weeks after treatment, the histomorphometric neointimal area was smaller with HCDCB versus uncoated HCB (2.39 ± 0.55 mm2 vs. 3.26 ± 0.72 mm2 , p = .038) and area stenosis (OCT) was less (11.6 ± 6.9% vs. 24.7 ± 9.7%, p = .022). No premature death occurred and no in-life clinical symptoms or treatment-associated thrombi were observed. HCDCB were found to inhibit excessive neointimal proliferation. Balloon adaption to different vessel diameters and shapes may provide drug-delivery in irregular lumen and facilitate balloon selection.