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BACKGROUND@#Biodegradable poly (l-lactic acid) (PLLA), a bio safe polymer with a large elastic modulus, is widely used in biodegradable medical devices. However, because of its poor mechanical properties, a PLLA strut must be made twice as thick as a metal strut for adequate blood vessel support. Therefore, the mechanical properties of a drug-eluting metal-based stents (MBS) and a bioresorbable vascular scaffolds (BVS) were evaluated and their safety and efficacy were examined via a long-term rabbit iliac artery model. @*METHODS@#The surface morphologies of the MBSs and BVSs were investigated via optical and scanning electron microscopy. An everolimus-eluting (EE) BVS or an EE-MBS was implanted into rabbit iliac arteries at a 1.1:1 stent-toartery ratio. Twelve months afterward, stented iliac arteries from each group were analyzed via X-ray angiography, optical coherence tomography (OCT), and histopathologic evaluation. @*RESULTS@#Surface morphology analysis of the EE coating on the MBS confirmed that it was uniform and very thin (4.7 lm). Comparison of the mechanical properties of the EE-MBS and EE-BVS showed that the latter outperformed the former in all aspects (radial force (2.75 vs. 0.162 N/mm), foreshortening (0.24% vs. 1.9%), flexibility (0.52 vs. 0.19 N), and recoil (3.2% vs. 6.3%). At all time points, the percent area restenosis was increased in the EE-BVS group compared to the EE-MBS group. The OCT and histopathological analyses indicate no significant changes in strut thickness. @*CONCLUSION@#BVSs with thinner struts and shorter resorption times should be developed. A comparable long-term safety/efficacy evaluation after complete absorption of BVSs should be conducted.
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BACKGROUND@#We have designed a reinforced drug-loaded vascular graft composed of polycaprolactone (PCL) and polydioxanone (PDO) via a combination of electrospinning/3D printing approaches. To evaluate its potential for clinical application, we compared the in vivo blood compatibility and performance of PCL/PDO ? 10%DY grafts doped with an antithrombotic drug (dipyridamole) with a commercial expanded polytetrafluoroethylene (e-PTFE) graft in a porcine model. @*METHODS@#A total of 10 pigs (weight: 25–35 kg) were used in this study. We made a new 5-mm graft with PCL/PDO composite nanofiber via the electrospinning technique. We simultaneously implanted a commercially available e-PTFE graft (n = 5) and our PCL/PDO ? 10%DY graft (n = 5) into the carotid arteries of the pigs. No anticoagulant/antiplatelet agent was administered during the follow-up period, and ultrasonography was performed weekly to confirm the patency of the two grafts in vivo. Four weeks later, we explanted and compared the performance of the two grafts by histological analysis and scanning electron microscopy (SEM). @*RESULTS@#No complications, such as sweating on the graft or significant bleeding from the needle hole site, were seen in the PCL/PDO ? 10%DY graft immediately after implantation. Serial ultrasonographic examination and immunohistochemical analysis demonstrated that PCL/PDO ? 10%DY grafts showed normal physiological blood flow and minimal lumen reduction, and pulsed synchronously with the native artery at 4 weeks after implantation. However, all e-PTFE grafts occluded within the study period. The luminal surface of the PCL/PDO ? 10%DY graft in the transitional zone was fully covered with endothelial cells as observed by SEM. @*CONCLUSION@#The PCL/PDO ? 10%DY graft was well tolerated, and no adverse tissue reaction was observed in porcine carotid models during the short-term follow-up. Colonization of the graft by host endothelial and smooth muscle cells coupled with substantial extracellular matrix production marked the regenerative capability. Thus, this material may be an ideal substitute for vascular reconstruction and bypass surgeries. Long-term observations will be necessary to determine the anti-thrombotic and remodeling potential of this device.
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Background and Objectives@#This clinical trial was conducted to evaluate the safety and efficacy of D+Storm™ drug-eluting stent (DES) and BioMatrix Flex™ DES. @*Methods@#This study was a multicenter, subject-single-blind, randomized, and confirmed comparative clinical trial. According to the inclusion criteria, those diagnosed with stable angina, unstable angina, silent ischemia, or non-ST-segment myocardial infarction were selected among patients with coronary artery stenosis as subjects. Among the subjects with 50% stenosis on coronary angiography, the experiment was performed on those who had a lesion with reference vessel 2.5–4.0 mm in diameter and ≤40 mm in length. The primary endpoint was an in-segment late loss and the secondary endpoints were in-stent late lumen loss, stent malapposition, the incidence of mortality, myocardial infarction, reoperation, and stent thrombosis at 36 weeks. @*Results@#57 patients in the D+Storm™ DES group and 55 patients in the BioMatrix Flex™ DES group were enrolled in the study. Fifty-seven patients in the D+Storm™ DES group and Fifty-five patients in the BioMatrix Flex™ DES group were enrolled in the study. An average of in-segment late lumen loss was 0.08±0.13 mm in the D+Storm™ DES group and 0.14±0.32mm in the BioMatrix Flex™ DES group with no significant difference between the 2 groups (p=0.879). In addition, there was no significant difference in adverse events between D+Storm™ DES and BioMatrix Flex™ DES. @*Conclusions@#This study demonstrated the clinical effectiveness and safety of D+Storm™ DES implantation in patients with coronary artery disease over a 36-week follow-up period.
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Background@#Titanium dioxide films exhibit good biocompatibility and may be effective as drug-binding matrices for drug-eluting stents. We conducted a mid-term evaluation of a novel polymer-free everolimus-eluting stent using nitrogen-doped titanium dioxide film deposition (TIGEREVOLUTION® ) in comparison with a commercial durable polymer everolimus-eluting stent (XIENCE Alpine® ) in a porcine coronary restenosis model. @*Methods@#Twenty-eight coronary arteries from 14 mini-pigs were randomly allocated to TIGEREVOLUTION® stent and XIENCE Alpine® stent groups. The stents were implanted in the coronary artery at a 1.1–1.2:1 stent-to-artery ratio. Eleven stented coronary arteries in each group were finally analyzed using coronary angiography, optical coherence tomography, and histopathologic evaluation 6 months after stenting. @*Results@#Quantitative coronary analysis showed no significant differences in the preprocedural, post-procedural, and 6-month lumen diameters between the groups. In the volumetric analysis of optical coherence tomography at 6 months, no significant differences were observed in stent volume, lumen volume, and percent area stenosis between the groups. There were no significant differences in injury score, inflammation score, or fibrin score between the groups, although the fibrin score was zero in the TIGEREVOLUTION® stent group (0 vs. 0.07 ± 0.11, P = 0.180). @*Conclusion@#Preclinical evaluation, including optical coherence tomographic findings 6 months after stenting, demonstrated that the TIGEREVOLUTION® stent exhibited efficacy and safety comparable with the XIENCE Alpine® stent, supporting the need for further clinical studies on the TIGEREVOLUTION® stent.
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Background@#Titanium dioxide films exhibit good biocompatibility and may be effective as drug-binding matrices for drug-eluting stents. We conducted a mid-term evaluation of a novel polymer-free everolimus-eluting stent using nitrogen-doped titanium dioxide film deposition (TIGEREVOLUTION® ) in comparison with a commercial durable polymer everolimus-eluting stent (XIENCE Alpine® ) in a porcine coronary restenosis model. @*Methods@#Twenty-eight coronary arteries from 14 mini-pigs were randomly allocated to TIGEREVOLUTION® stent and XIENCE Alpine® stent groups. The stents were implanted in the coronary artery at a 1.1–1.2:1 stent-to-artery ratio. Eleven stented coronary arteries in each group were finally analyzed using coronary angiography, optical coherence tomography, and histopathologic evaluation 6 months after stenting. @*Results@#Quantitative coronary analysis showed no significant differences in the preprocedural, post-procedural, and 6-month lumen diameters between the groups. In the volumetric analysis of optical coherence tomography at 6 months, no significant differences were observed in stent volume, lumen volume, and percent area stenosis between the groups. There were no significant differences in injury score, inflammation score, or fibrin score between the groups, although the fibrin score was zero in the TIGEREVOLUTION® stent group (0 vs. 0.07 ± 0.11, P = 0.180). @*Conclusion@#Preclinical evaluation, including optical coherence tomographic findings 6 months after stenting, demonstrated that the TIGEREVOLUTION® stent exhibited efficacy and safety comparable with the XIENCE Alpine® stent, supporting the need for further clinical studies on the TIGEREVOLUTION® stent.
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BACKGROUND: Patients with acute myocardial infarction (AMI) have worse clinical outcomes than those with stable coronary artery disease despite revascularization. Non-culprit lesions of AMI also involve more adverse cardiovascular events. This study aimed to investigate the influence of AMI on endothelial function, neointimal progression, and inflammation in target and non-target vessels. METHODS: In castrated male pigs, AMI was induced by balloon occlusion and reperfusion into the left anterior descending artery (LAD). Everolimus-eluting stents (EES) were implanted in the LAD and left circumflex (LCX) artery 2 days after AMI induction. In the control group, EES were implanted in the LAD and LCX in a similar fashion without AMI induction. Endothelial function was assessed using acetylcholine infusion before enrollment, after the AMI or sham operation, and at 1 month follow-up. A histological examination was conducted 1 month after stenting. RESULTS: A total of 10 pigs implanted with 20 EES in the LAD and LCX were included. Significant paradoxical vasoconstriction was assessed after acetylcholine challenge in the AMI group compared with the control group. In the histologic analysis, the AMI group showed a larger neointimal area and larger area of stenosis than the control group after EES implantation. Peri-strut inflammation and fibrin formation were significant in the AMI group without differences in injury score. The non-target vessel of the AMI also showed similar findings to the target vessel compared with the control group. CONCLUSION: In the pig model, AMI events induced endothelial dysfunction, inflammation, and neointimal progression in the target and non-target vessels.
Subject(s)
Humans , Male , Acetylcholine , Arteries , Balloon Occlusion , Constriction, Pathologic , Coronary Artery Disease , Drug-Eluting Stents , Endothelium , Fibrin , Follow-Up Studies , Inflammation , Myocardial Infarction , Reperfusion , Stents , Swine , VasoconstrictionABSTRACT
Crohn's disease and ulcerative colitis are the two major types of inflammatory bowel disease, and affect mainly the gastrointestinal tract but also have extraintestinal sequelae, such as arterial and venous thromboembolism. Thromboembolic complications, particularly pulmonary thromboembolism, can be life threatening and require prompt management with anticoagulants. Conventional vitamin K antagonists have been used for the treatment of thromboembolic complications, but the development of novel oral anticoagulants has shifted the paradigm. We report a case of a 42-year-old female with ulcerative colitis who experienced an acute flare-up due to cytomegalovirus superinfection with pulmonary thromboembolism. She was treated with oral mesalamine, intravenous steroid and ganciclovir and low-molecular-weight heparin, followed by rivaroxaban, a novel oral anticoagulant. Her symptoms resolved after treatment, and no recurrence was noted during a 6-month post-treatment follow-up.
Subject(s)
Adult , Female , Humans , Anticoagulants , Colitis , Colitis, Ulcerative , Crohn Disease , Cytomegalovirus , Follow-Up Studies , Ganciclovir , Gastrointestinal Tract , Heparin, Low-Molecular-Weight , Inflammatory Bowel Diseases , Mesalamine , Pulmonary Embolism , Recurrence , Rivaroxaban , Superinfection , Ulcer , Venous Thromboembolism , Vitamin KABSTRACT
BACKGROUND AND OBJECTIVES: Artemisinin and dihydroartemisinin are drugs used to treat malaria. These drugs suppress inflammatory reactions. The aim of this study was to examine the anti-intima hyperplasia effect of a novel drug-eluting stent with artemisinin or dihydroartemisinin in a porcine coronary restenosis model. MATERIALS AND METHODS: Pigs were randomized into four groups; in the first, the coronary arteries (20 pigs, a total of 40 coronary arteries, with 10 coronary arteries in each group) was implanted with bare metal stents (BMS, n=10); the second group was given polymer-coated stents (PCS, n=10); the third group was treated with artemisinin-eluting stents (AES, n=10); and the fourth group was given dihydroartemisinin-eluting stents (DAES, n=10). Histopathologic analysis was performed 28 days after stenting. RESULTS: The injury and fibrin scores among the four groups were not significantly different. However, the internal elastic lamina, lumen area, and neointima area were significantly different. Moreover, the percent area of stenosis (46.2±18.66% in BMS vs. 89.4±10.92% in PCS vs. 83.3±17.07% in AES vs. 36.7±11.20% in DAES, p<0.0001) and inflammation score (1.0 [range: 1.0-1.0] vs. 3.0 [range: 2.25-3.0] vs. 3.0 [range: 1.0-3.0] vs. 2.0 [range: 1.75-3.0] in BMS, PCS, AES, and DAES, respectively; p<0.001) were markedly decreased in the DAES group compared to the PCS group. CONCLUSION: DES, which uses a natural substance, dihydroartemisinin, showed a neointima and inflammatory suppressive effect in a porcine coronary restenosis model.
Subject(s)
Constriction, Pathologic , Coronary Restenosis , Coronary Vessels , Drug-Eluting Stents , Fibrin , Hyperplasia , Inflammation , Malaria , Neointima , Stents , SwineABSTRACT
Nontuberculous mycobacteria (NTM) have been increasingly recognized as an important cause of chronic pulmonary infections. The Mycobacterium avium complex (MAC), which is composed of two species, Mycobacterium avium and Mycobacterium intracelluare, is the most commonly encountered pathogen associated with NTM lung disease. MAC pulmonary infection typically presents in a fibrocavitary form or a nodular bronchiectatic form. However, there have been atypical presentations of MAC pulmonary infections, including solitary pulmonary nodules (SPN). There have been several previous reports of SPN due to MAC infection in the United States, Japan, and Korea. In 2009, Sekine and colleagues reported a case of MAC pulmonary infection presenting with multiple nodules. To date, however, there have been no cases of NTM lung infection with multiple cavitary pulmonary nodules, and neither a fibrotic change nor nodular bronchiectasis. The present case showed a multiple cavitating nodular lung infection due to MAC, which is very rare and different from the typical presentation of MAC pulmonary infections. We also showed that percutaneous transthoracic needle aspiration can be a useful diagnostic tool to evaluate a case of multiple cavitary nodules.
Subject(s)
Bronchiectasis , Japan , Korea , Lung , Lung Diseases , Mycobacterium avium , Mycobacterium avium Complex , Mycobacterium , Needles , Nontuberculous Mycobacteria , Solitary Pulmonary Nodule , United StatesABSTRACT
Myocardial infarction (MI) is a complication that can occur after endoscopic submucosal dissection (ESD). However, very few reports are available about this complication. A 71-year-old male, who had two drug eluting stents inserted due to ischemic heart disease, was referred to the Division of Gastroenterology for ESD of a lesion suspicious of early gastric cancer. ESD was performed after dual antiplatelet agents were discontinued and bridging therapy with low molecular weight heparin (LMWH) was initiated. However, MI occurred immediately after the ESD procedure. A coronary angiogram did not show any significant stent thrombosis or restenosis. The patient recovered spontaneously. Here, we report a case of MI that occurred after ESD under bridging therapy with LMWH.
Subject(s)
Aged , Humans , Male , Drug-Eluting Stents , Gastroenterology , Heparin , Heparin, Low-Molecular-Weight , Myocardial Infarction , Myocardial Ischemia , Platelet Aggregation Inhibitors , Stents , Stomach Neoplasms , ThrombosisABSTRACT
Statins have pleiotropic effects, which include the inhibition of neointima hyperplasia, the inhibition of vascular inflammation, and platelet inhibition. The aim of this study was to examine the effect of an atorvastatin-eluting stent (AES) in a rabbit iliac artery overstretch restenosis model. Ten rabbits were used in this study (10 rabbits, 10 iliac arteries for each stent). An AES and paclitaxel-eluting stent (PES) were implanted in the left and right iliac arteries in a rabbit (2 stents in each rabbit). The stents were deployed with oversizing (stent/artery ratio 1.3:1), and histopathologic analysis was assessed at 28 days after stenting. There were no significant differences in the injury score, lumen area, or inflammation score. There were significant differences in the neointimal area (0.7+/-0.18 mm2 in the AES group vs. 0.4+/-0.25 mm2 in the PES group, p<0.01), in the percentage stenosis area (14.8+/-5.06% in the AES group vs. 10.5+/-6.80% in the PES group, p<0.05), and in the fibrin score (0.4+/-0.51 in the AES group vs. 2.7+/-0.48 in the PES group, p<0.001). Although the AES did not suppress neointimal hyperplasia compared with the PES, it showed a superior arterial healing effect in a rabbit iliac artery overstretch restenosis model.
Subject(s)
Rabbits , Blood Platelets , Constriction, Pathologic , Coronary Restenosis , Drug-Eluting Stents , Fibrin , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Hyperplasia , Iliac Artery , Inflammation , Neointima , StentsABSTRACT
Statins have pleiotropic effects, which include the inhibition of neointima hyperplasia, the inhibition of vascular inflammation, and platelet inhibition. The aim of this study was to examine the effect of an atorvastatin-eluting stent (AES) in a rabbit iliac artery overstretch restenosis model. Ten rabbits were used in this study (10 rabbits, 10 iliac arteries for each stent). An AES and paclitaxel-eluting stent (PES) were implanted in the left and right iliac arteries in a rabbit (2 stents in each rabbit). The stents were deployed with oversizing (stent/artery ratio 1.3:1), and histopathologic analysis was assessed at 28 days after stenting. There were no significant differences in the injury score, lumen area, or inflammation score. There were significant differences in the neointimal area (0.7+/-0.18 mm2 in the AES group vs. 0.4+/-0.25 mm2 in the PES group, p<0.01), in the percentage stenosis area (14.8+/-5.06% in the AES group vs. 10.5+/-6.80% in the PES group, p<0.05), and in the fibrin score (0.4+/-0.51 in the AES group vs. 2.7+/-0.48 in the PES group, p<0.001). Although the AES did not suppress neointimal hyperplasia compared with the PES, it showed a superior arterial healing effect in a rabbit iliac artery overstretch restenosis model.