Mid-Term Outcomes of Novel Covered Stent with Biodegradable Membrane in Porcine Coronary Artery Perforation

Abstract

Background: Currently, commercially covered stents are the main treatment for coronary artery perforation (CAP), but without satisfied late-term outcomes when compared to drug-eluting stents (DES). This study seeks to report a new covered stent to treat porcine CAP, which is manufactured with DES and a biodegradable membrane fabricated by poly-L-lactic acid (PLLA) polymer. Methods: Experimental swines experienced CAP in proximal-middle of right coronary artery (RCA) by non-compliant balloon burst, and covered stent was deployed in breach segment. Meanwhile, coronary angiography (CAG), optical coherence tomography (OCT), histological light microscopy and scan electron microscopy were performed to characterize the performance of covered stent. Results: Seven swines were used for this study. Two swines were euthanasia at 14 days and 28 days after procedure, respectively. The remaining 5 kept alive until sacrifice at six months. CAG at six months showed total occlusion at the stented segment of RCA in all swines. The interventional revascularization of occlusion lesion was instituted in two swines. After recanalizing occlusion lesion, OCT examination visualized diffuse heterogeneous fibrous plaques, as well as organized thrombosis, lipid deposits and several neoatherosclerosis in the occluded segment. Serial histopathologic and electron microscopies at 14 days, 28 days and six months revealed gradual occlusive vessel lumen with diffuse heterogeneous fibroplasia, smooth muscle proliferation, inflammation response and local neoatherosclerosis, moreover with identification of PLLA polymer membrane degradability. Conclusions: The new covered stent with biodegradable membrane could seal urgent coronary breach and prevent experimental swines death, but with all stent occlusion in mid-term (six months) follow-up, which might be attributed to diffuse heterogeneous fibroplasia, smooth muscle proliferation, inflammation response and local neoatherosclerosis with the degradation of PLLA membrane.

The Best Strategy for Black Hole Phenomenon between Intravascular Ultrasound and Optical Coherence Tomography

“…The black hole (BH) phenomenon is when an intraluminal restenotic lesion image is obtained by intravascular ultrasound (IVUS) and optical coherence tomography (OCT) [7][8][9][10][11][12]. The development of ISR involves multiple factors, including biological, mechanical, and patient-and operator-related factors [13][14][15]. Intracoronary imaging is crucial for determining the specific mechanism of ISR, enabling tailored treatment strategies based on the identified cause.…”

“…The cause of ISR is multifactorial and can be attributed to various biological, mechanical, and procedural factors [13][14][15]. The mechanical factors primarily include stent expansion or fracture, whereas the biological factors involve localized inflammation leading to excessive neointimal growth and late neoatherosclerosis.…”