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1.
Nature ; 509(7502): 641-4, 2014 May 29.
Article in English | MEDLINE | ID: mdl-24747400

ABSTRACT

Despite the introduction of antiproliferative drug-eluting stents, coronary heart disease remains the leading cause of death in the United States. In-stent restenosis and bypass graft failure are characterized by excessive smooth muscle cell (SMC) proliferation and concomitant myointima formation with luminal obliteration. Here we show that during the development of myointimal hyperplasia in human arteries, SMCs show hyperpolarization of their mitochondrial membrane potential (ΔΨm) and acquire a temporary state with a high proliferative rate and resistance to apoptosis. Pyruvate dehydrogenase kinase isoform 2 (PDK2) was identified as a key regulatory protein, and its activation proved necessary for relevant myointima formation. Pharmacologic PDK2 blockade with dichloroacetate or lentiviral PDK2 knockdown prevented ΔΨm hyperpolarization, facilitated apoptosis and reduced myointima formation in injured human mammary and coronary arteries, rat aortas, rabbit iliac arteries and swine (pig) coronary arteries. In contrast to several commonly used antiproliferative drugs, dichloroacetate did not prevent vessel re-endothelialization. Targeting myointimal ΔΨm and alleviating apoptosis resistance is a novel strategy for the prevention of proliferative vascular diseases.


Subject(s)
Aorta/injuries , Arteries/injuries , Constriction, Pathologic/prevention & control , Dichloroacetic Acid/pharmacology , Dichloroacetic Acid/therapeutic use , Tunica Intima/drug effects , Tunica Intima/pathology , Angioplasty, Balloon/adverse effects , Animals , Aorta/drug effects , Aorta/pathology , Apoptosis/drug effects , Arteries/drug effects , Arteries/pathology , Cell Proliferation/drug effects , Constriction, Pathologic/pathology , Coronary Vessels/drug effects , Coronary Vessels/injuries , Coronary Vessels/pathology , Disease Models, Animal , Enzyme Activation/drug effects , Gene Knockdown Techniques , Humans , Hyperplasia/drug therapy , Hyperplasia/pathology , Iliac Artery/drug effects , Iliac Artery/injuries , Iliac Artery/pathology , Mammary Arteries/drug effects , Mammary Arteries/injuries , Mammary Arteries/pathology , Membrane Potential, Mitochondrial/drug effects , Mitochondria, Heart/drug effects , Mitochondria, Heart/metabolism , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/pathology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/deficiency , Protein Serine-Threonine Kinases/genetics , Pyruvate Dehydrogenase Acetyl-Transferring Kinase , Rabbits , Rats , Secondary Prevention , Stents/adverse effects , Swine , Tunica Intima/injuries
2.
Am Heart J ; 206: 61-71, 2018 12.
Article in English | MEDLINE | ID: mdl-30342296

ABSTRACT

BACKGROUND: Regulatory decisions approving new coronary drug-eluting stent (DES) require mechanistic observations of angiographic late lumen loss (LLL). Patient safety and device approval times could be enhanced if angiographic follow-up data were found to be generalizable across jurisdictions and geographies. The objectives were to assess the comparability of in-segment LLL in Eastern and Western DES populations using the world's largest compilation of follow-up quantitative coronary angiography data. METHODS: Data from 4 manufacturers involving 29 DES clinical trials in Eastern and Western hemispheres were compiled. "East" and "West" cohorts were defined by trial location. Independent core laboratories quantified in-segment LLL for all studies. East and West were compared before and after adjustment for clinical and anatomic covariates known to correlate with LLL via conditioning on propensity score quintiles. An international panel of experts and regulators prospectively established a clinically meaningful difference between East and West mean in-segment LLL of ±0.40 mm. RESULTS: The data set comprised 2,047 East and 4,456 West patients. Unadjusted mean ± SD for West and East in-segment LLL (mm) was 0.25 ± 0.46 and 0.12 ± 0.42, respectively (difference 0.13 mm; 95% CI 0.11-0.16). Propensity score-adjusted in-segment LLL East and West least squares means were 0.11 and 0.26 mm, respectively (difference 0.15 mm; 95% CI 0.13-0.18). CONCLUSIONS: In the world's largest compilation of DES protocol 8- to 13-month angiographic follow-up data, clinically meaningful comparability of in-segment LLL by independent core laboratory quantitative coronary angiography in East and West cohorts was demonstrated in both unadjusted and adjusted comparisons. These findings suggest that DES LLL, once characterized, could be generalized across regulatory jurisdictions over the course of global registration efforts.


Subject(s)
Coronary Artery Disease/surgery , Coronary Vessels/diagnostic imaging , Drug-Eluting Stents , Percutaneous Coronary Intervention/methods , Racial Groups/statistics & numerical data , Aged , Coronary Artery Disease/diagnosis , Coronary Vessels/surgery , Female , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Complications , Propensity Score , Prosthesis Design , Retrospective Studies
3.
Catheter Cardiovasc Interv ; 91(5): 874-883, 2018 04 01.
Article in English | MEDLINE | ID: mdl-28707349

ABSTRACT

BACKGROUND: In vivo assessment of bioresorbable scaffold (BRS) is of growing clinical interest. The novel 60MHz high-definition intravascular ultrasound (HD-IVUS) has been developed to overcome the limitations of conventional 40 MHz IVUS. This study aimed to evaluate the performance and limitations of 60 MHz HD-IVUS compared with 40 MHz IVUS with respect to polymeric-strut visualization, quantitative and qualitative analysis, and feasibility of high-speed pullback in the assessment of BRS. METHODS AND RESULTS: In a bench-test model, 361 struts were analyzed to evaluate the influence of ultrasound-beam angles and proximity of adjacent struts on IVUS visualization of BRS struts. Various settings were created by deforming the BRS and positioning the transducer offcenter. In an in vivo swine coronary model, scaffold and lumen areas, degree of visible external elastic membrane, incomplete strut apposition, and strut fracture were evaluated in 59 matched cross-sections obtained at conventional (0.5 mm/sec) and high speed (10 mm/sec) pullbacks. Both studies utilized optical coherence tomography (OCT) as reference. Overall, 60 MHz HD-IVUS demonstrated significantly improved visualization of polymeric struts compared with 40 MHz IVUS (well-visualized: 84.5% vs 62.3%, not visible: 4.4% vs 13.9%, respectively. P < 0.001), which was less affected by the beam angle and adjacent strut proximity. In the in vivo model, 60-MHz HD-IVUS showed better agreement of area measurements and strut abnormalities with OCT than 40 MHz IVUS. These findings were also confirmed on high-speed pullback images of 60 MHz HD-IVUS. CONCLUSION: As referenced to OCT, this study showed superiority of 60 MHz HD-IVUS over 40 MHz IVUS in the assessment of BRS with feasibility of high-speed pullback imaging.


Subject(s)
Absorbable Implants , Coronary Vessels/diagnostic imaging , Coronary Vessels/surgery , Percutaneous Coronary Intervention/instrumentation , Tomography, Optical Coherence , Ultrasonography, Interventional , Animals , Feasibility Studies , Female , Materials Testing , Models, Anatomic , Models, Animal , Predictive Value of Tests , Prosthesis Design , Sus scrofa
4.
Circ J ; 82(9): 2233-2239, 2018 08 24.
Article in English | MEDLINE | ID: mdl-29962385

ABSTRACT

For more than 10 years, the Harmonization by Doing (HBD) program, a joint effort by members from academia, industry and regulators from the United States of America (USA) and Japan, has been working to increase timely regulatory approval for cardiovascular devices through the development of practical global clinical trial paradigms. Consistent with this mission and in recognition of the increasing global public health effects of critical limb ischemia (CLI), academic and government experts from the USA and Japan have developed a basic framework of global clinical trials for endovascular devices for CLI. Despite differences in medical and regulatory environments and complex patient populations in both countries, we developed a pathway for the effective design and conduct of global CLI device studies by utilizing common study design elements such as patients' characteristics and study endpoints, and minimizing the effect of important clinical differences. Some of the key recommendations for conducting global CLI device studies are: including patients on dialysis; using a composite primary endpoint for effectiveness that includes 6-month post-procedure therapeutic success and target vessel patency; and using a 30-day primary safety endpoint of perioperative death and major adverse limb events. The proposed approach will be uniquely beneficial in facilitating both the initiation and interpretation of CLI studies and accelerating worldwide CLI device development and innovation.


Subject(s)
Clinical Trials as Topic , Extremities/blood supply , Internationality , Ischemia/surgery , Peripheral Arterial Disease/surgery , Research Design , Stents , Aged , Endovascular Procedures , Humans , Japan , United States , Vascular Patency/physiology
5.
Am Heart J ; 183: 1-9, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27979031

ABSTRACT

BACKGROUND: Fractional flow reserve (FFR) prior to percutaneous coronary intervention (PCI) is useful to guide treatment. Whether post-PCI FFR assessment might have clinical impact is controversial. The aim of this study is to evaluate the range of post-PCI FFR values and analyze the relationship between post-PCI FFR and clinical outcomes. METHODS: We systematically searched the PubMed, EMBASE, and Cochrane Library databases with cross-referencing of articles reporting post-PCI FFR and correlating post-PCI FFR values and clinical outcomes. The outcomes of interest were the immediate post-PCI FFR values and the correlations between post-PCI FFR and the incidence of repeat intervention and major adverse cardiac events (MACE). RESULTS: From 1995 to 2015, a total of 105 studies (n = 7470) were included, with 46 studies reporting post-PCI FFR and 59 studies evaluating relationship between post-PCI and clinical outcomes up to 30 months after PCI. Overall, post-PCI FFR values demonstrated a normal distribution with a mean value of 0.90 ± 0.04. There was a positive correlation between the percentage of stent use and post-PCI FFR (P < .0001). Meta-regression analysis indicated that higher post-PCI FFR values were associated with reduced rates of repeat intervention (P < .0001) and MACE (P = .0013). A post-PCI FFR ≥0.90 was associated with significantly lower risk of repeat PCI (odds ratio 0.43, 95% CI 0.34-0.56, P < .0001) and MACE (odds ratio 0.71, 95% CI 0.59-0.85, P = .0003). CONCLUSIONS: FFR measurement after PCI was associated with prognostic significance. Further investigation is required to assess the role of post-PCI FFR and validate cutoff values in contemporary clinical practice.


Subject(s)
Coronary Stenosis/physiopathology , Fractional Flow Reserve, Myocardial , Percutaneous Coronary Intervention , Adult , Aged , Coronary Stenosis/therapy , Female , Humans , Male , Middle Aged , Stents
6.
Int Heart J ; 58(3): 435-440, 2017 May 31.
Article in English | MEDLINE | ID: mdl-28539564

ABSTRACT

Cardiac regeneration strategies using stem cells have shown variable and inconsistent results with respect to patient cardiac function and clinical outcomes. There has been increasing consensus that improving the efficiency of delivery may improve results. The Helix transendocardial delivery system (BioCardia Inc.) has been developed to enable percutaneous transendocardial biotherapeutic delivery. Therefore, we evaluated cell retention using this unique system compared with direct transepicardial injection and intracoronary infusion in an animal model.Twelve healthy swine were used in this study. 18Fluorodeoxyglucose (FDG)-labeled bone marrow mononuclear cells were delivered via percutaneous transendocardial route using the Helix system (TE group, n = 5), via direct transepicardial injection using a straight 27-gauge needle in an open chest procedure (TP group, n = 4), or via percutaneous intracoronary (IC) infusion (IC group, n = 3). One hour after cell delivery, the distribution of injected cells within the myocardium was assessed by PET-CT. Regions of interest were defined and their signals were compared in each group. Retention rates were calculated as a percentage of the comparing signal.The distribution of injected cells in the myocardium was higher in the TE group (17.9%) than in the TP group (6.0%, versus TE, P < 0.001) and the IC group (1.0%, versus TE, P < 0.001). Consistent with previous reports, there were signal distributions in the lungs, liver, and kidneys in qualitative whole body PET assessment.TE cell delivery using a helical infusion catheter is more efficient in cell retention than either TP delivery or IC delivery using PET-CT analysis.


Subject(s)
Cardiac Catheters , Cell- and Tissue-Based Therapy/instrumentation , Drug Delivery Systems/instrumentation , Myocardial Ischemia/therapy , Stem Cell Transplantation/methods , Stem Cells/cytology , Animals , Disease Models, Animal , Endocardium , Equipment Design , Female , Myocardial Ischemia/diagnosis , Positron Emission Tomography Computed Tomography , Swine
7.
Radiology ; 280(3): 826-36, 2016 09.
Article in English | MEDLINE | ID: mdl-27332865

ABSTRACT

Purpose To quantitatively determine the limit of detection of marrow stromal cells (MSC) after cardiac cell therapy (CCT) in swine by using clinical positron emission tomography (PET) reporter gene imaging and magnetic resonance (MR) imaging with cell prelabeling. Materials and Methods Animal studies were approved by the institutional administrative panel on laboratory animal care. Seven swine received 23 intracardiac cell injections that contained control MSC and cell mixtures of MSC expressing a multimodality triple fusion (TF) reporter gene (MSC-TF) and bearing superparamagnetic iron oxide nanoparticles (NP) (MSC-TF-NP) or NP alone. Clinical MR imaging and PET reporter gene molecular imaging were performed after intravenous injection of the radiotracer fluorine 18-radiolabeled 9-[4-fluoro-3-(hydroxyl methyl) butyl] guanine ((18)F-FHBG). Linear regression analysis of both MR imaging and PET data and nonlinear regression analysis of PET data were performed, accounting for multiple injections per animal. Results MR imaging showed a positive correlation between MSC-TF-NP cell number and dephasing (dark) signal (R(2) = 0.72, P = .0001) and a lower detection limit of at least approximately 1.5 × 10(7) cells. PET reporter gene imaging demonstrated a significant positive correlation between MSC-TF and target-to-background ratio with the linear model (R(2) = 0.88, P = .0001, root mean square error = 0.523) and the nonlinear model (R(2) = 0.99, P = .0001, root mean square error = 0.273) and a lower detection limit of 2.5 × 10(8) cells. Conclusion The authors quantitatively determined the limit of detection of MSC after CCT in swine by using clinical PET reporter gene imaging and clinical MR imaging with cell prelabeling. (©) RSNA, 2016 Online supplemental material is available for this article.


Subject(s)
Genes, Reporter , Heart/diagnostic imaging , Mesenchymal Stem Cell Transplantation , Molecular Imaging/methods , Multimodal Imaging/methods , Animals , Fluorine Radioisotopes , Guanine/analogs & derivatives , Magnetic Resonance Imaging , Positron Emission Tomography Computed Tomography , Radiopharmaceuticals , Swine
8.
Radiology ; 280(3): 815-25, 2016 09.
Article in English | MEDLINE | ID: mdl-27308957

ABSTRACT

Purpose To use multimodality reporter-gene imaging to assess the serial survival of marrow stromal cells (MSC) after therapy for myocardial infarction (MI) and to determine if the requisite preclinical imaging end point was met prior to a follow-up large-animal MSC imaging study. Materials and Methods Animal studies were approved by the Institutional Administrative Panel on Laboratory Animal Care. Mice (n = 19) that had experienced MI were injected with bone marrow-derived MSC that expressed a multimodality triple fusion (TF) reporter gene. The TF reporter gene (fluc2-egfp-sr39ttk) consisted of a human promoter, ubiquitin, driving firefly luciferase 2 (fluc2), enhanced green fluorescent protein (egfp), and the sr39tk positron emission tomography reporter gene. Serial bioluminescence imaging of MSC-TF and ex vivo luciferase assays were performed. Correlations were analyzed with the Pearson product-moment correlation, and serial imaging results were analyzed with a mixed-effects regression model. Results Analysis of the MSC-TF after cardiac cell therapy showed significantly lower signal on days 8 and 14 than on day 2 (P = .011 and P = .001, respectively). MSC-TF with MI demonstrated significantly higher signal than MSC-TF without MI at days 4, 8, and 14 (P = .016). Ex vivo luciferase activity assay confirmed the presence of MSC-TF on days 8 and 14 after MI. Conclusion Multimodality reporter-gene imaging was successfully used to assess serial MSC survival after therapy for MI, and it was determined that the requisite preclinical imaging end point, 14 days of MSC survival, was met prior to a follow-up large-animal MSC study. (©) RSNA, 2016 Online supplemental material is available for this article.


Subject(s)
Genes, Reporter , Mesenchymal Stem Cell Transplantation/methods , Molecular Imaging , Multimodal Imaging , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/therapy , Animals , Female , Luciferases, Firefly/metabolism , Luminescent Measurements , Mice , Mice, Nude , Positron-Emission Tomography , Transfection
9.
Am Heart J ; 182: 103-110, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27914489

ABSTRACT

BACKGROUND: The contemporary evaluation of novel drug-eluting stents (DES) includes mechanistic observations that characterize postdeployment stent behavior. Quantification of late lumen loss due to neointimal hyperplasia 8-13 months after stent implantation, via quantitative coronary angiography (QCA), constitutes such an observation and is required by most regulatory authorities. Late lumen loss, as determined by QCA, has been validated as a surrogate for clinical endpoints such as target vessel revascularization. The mechanistic response to DES has not been directly compared across predominantly Asian or Western populations, whereas understanding their comparability across geographic populations could enhance global DES evaluation. OBJECTIVE: The East-West late lumen loss study is designed to demonstrate whether the residual differences in late lumen loss, as assessed by QCA, is different between Eastern and Western DES recipients from studies with protocol angiography at 8-13 months of follow-up. METHODS: Data from independent core laboratories that have characterized angiographic late lumen loss in DES clinical trials with protocol follow-up angiography will be compiled and dichotomized into Eastern and Western populations. A prospectively developed propensity score model incorporating clinical and anatomic variables affecting late lumen loss will be used to adjust comparisons of QCA measurements. CONCLUSION: Documentation of whether there are clinically meaningful differences in mechanistic response to DES implantation across genetically unique geographies could facilitate both the quality and efficiency of global device evaluation requiring invasive follow-up for novel stent designs.


Subject(s)
Angioplasty, Balloon, Coronary/instrumentation , Coronary Artery Disease , Coronary Restenosis , Drug-Eluting Stents , Prosthesis Failure , Angioplasty, Balloon, Coronary/adverse effects , Angioplasty, Balloon, Coronary/methods , Coronary Angiography/methods , Coronary Artery Disease/diagnosis , Coronary Artery Disease/therapy , Coronary Restenosis/diagnosis , Coronary Restenosis/ethnology , Coronary Restenosis/etiology , Drug-Eluting Stents/adverse effects , Drug-Eluting Stents/standards , Equipment Failure Analysis/methods , Female , Humans , Male , Middle Aged , Observational Studies as Topic , Outcome and Process Assessment, Health Care/methods , Propensity Score , Prosthesis Failure/adverse effects , Prosthesis Failure/etiology , Racial Groups/statistics & numerical data , Randomized Controlled Trials as Topic , Retrospective Studies
10.
Catheter Cardiovasc Interv ; 85(3): E70-5, 2015 Feb 15.
Article in English | MEDLINE | ID: mdl-25331940

ABSTRACT

OBJECTIVE: To report our initial animal and human experience with a new multi-lumen catheter called MultiCross™ (Roxwood Medical, Inc.) in a porcine coronary model and patients with a chronic total occlusion (CTO). METHODS: Preclinical safety study was done in the coronary vasculature of a porcine model. In a clinical setting, patients with a CTO of a coronary artery (n = 5) were enrolled. After an initial unsuccessful attempt using a conventional guidewire, operators could use the MultiCross system. The primary efficacy endpoint was successful recanalization (technical success) and the primary safety endpoint was serious adverse events through 30 days post-procedure. RESULTS: The MultiCross catheter was used for all patients after failure of the initial attempt with a guidewire. Successful recanalization was achieved in all CTOs attempted (100%). No patients reported any adverse events at 30 days post-procedure. CONCLUSION: In this first-in-man experience, the MultiCross catheter has the potential to enhance crossing of CTOs.


Subject(s)
Cardiac Catheterization/instrumentation , Cardiac Catheters , Coronary Occlusion/therapy , Aged , Animals , Cardiac Catheterization/adverse effects , Chronic Disease , Coronary Angiography , Coronary Occlusion/diagnosis , Equipment Design , Female , Humans , Male , Materials Testing , Middle Aged , Models, Animal , Registries , Swine , Time Factors , Treatment Outcome
11.
Circulation ; 126(17): 2115-24, 2012 Oct 23.
Article in English | MEDLINE | ID: mdl-23008442

ABSTRACT

BACKGROUND: The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial assigned patients with type 2 diabetes mellitus to prompt coronary revascularization plus intensive medical therapy versus intensive medical therapy alone and reported no significant difference in mortality. Among patients selected for coronary artery bypass graft surgery, prompt coronary revascularization was associated with a significant reduction in death/myocardial infarction/stroke compared with intensive medical therapy. We hypothesized that clinical and angiographic risk stratification would affect the effectiveness of the treatments overall and within revascularization strata. METHODS AND RESULTS: An angiographic risk score was developed from variables assessed at randomization; independent prognostic factors were myocardial jeopardy index, total number of coronary lesions, prior coronary revascularization, and left ventricular ejection fraction. The Framingham Risk Score for patients with coronary disease was used to summarize clinical risk. Cardiovascular event rates were compared by assigned treatment within high-risk and low-risk subgroups. Overall, no outcome differences between the intensive medical therapy and prompt coronary revascularization groups were seen in any risk stratum. The 5-year risk of death/myocardial infarction/stroke was 36.8% for intensive medical therapy compared with 24.8% for prompt coronary revascularization among the 381 coronary artery bypass graft surgery-selected patients in the highest angiographic risk tertile (P=0.005); this treatment effect was amplified in patients with both high angiographic and high Framingham risk (47.3% intensive medical therapy versus 27.1% prompt coronary revascularization; P=0.010; hazard ratio=2.10; P=0.009). Treatment group differences were not significant in other clinical-angiographic risk groups within the coronary artery bypass graft surgery stratum, or in any subgroups within the percutaneous coronary intervention stratum. CONCLUSION: Among patients with diabetes mellitus and stable ischemic heart disease, a strategy of prompt coronary artery bypass graft surgery significantly reduces the rate of death/myocardial infarction MI/stroke in those with extensive coronary artery disease or impaired left ventricular function. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00006305.


Subject(s)
Angioplasty, Balloon, Coronary , Coronary Angiography , Coronary Artery Bypass , Diabetes Mellitus, Type 2/diagnostic imaging , Diabetes Mellitus, Type 2/therapy , Aged , Angioplasty, Balloon, Coronary/methods , Coronary Angiography/methods , Coronary Artery Bypass/methods , Diabetes Mellitus, Type 2/mortality , Female , Humans , Male , Middle Aged , Percutaneous Coronary Intervention/methods , Risk Factors , Treatment Outcome
12.
Circ J ; 77(7): 1714-8, 2013.
Article in English | MEDLINE | ID: mdl-23538483

ABSTRACT

BACKGROUND: Global medical devices have become more popular, but investment money for medical device development is not easily available in the market. Worldwide health-care budget constraints mean that efficient medical device development has become essential. To achieve efficient development, globalization is a key to success. Spending large amounts of money in different regions for medical device development is no longer feasible. METHODS AND RESULTS: In order to streamline processes of global medical device development, an academic, governmental, and industrial consortium, called the Harmonization by Doing program, has been set up. The program has been operating between Japan and the USA since 2003. The program has 4 working groups: (1) Global Cardiovascular Device Trials; (2) Study on Post-Market Registry; (3) Clinical Trials; and (4) Infrastructure and Methodology Regulatory Convergence and Communication. Each working group has as its goals the achievement of speedy and efficient medical device development in Japan and the USA. The program has held multiple international meetings to deal with obstacles against efficient medical device development. CONCLUSIONS: This kind of program is very important to deliver novel medical devices. Involvement of physicians in this type of activity is also very helpful to achieve these goals.


Subject(s)
Biomedical Research , Equipment Design , International Cooperation , Medical Device Legislation , Product Surveillance, Postmarketing , Registries , Cardiovascular Diseases/therapy , Clinical Trials as Topic , Female , Humans , Japan , Male , United States
13.
Cardiovasc Revasc Med ; 52: 67-74, 2023 07.
Article in English | MEDLINE | ID: mdl-36870799

ABSTRACT

As medical device development becomes increasingly global, the opportunities and potential advantages offered by international clinical trial and regulatory approval strategies are also growing. In particular, medical device clinical trials involving sites in both the United States and Japan and intended to support marketing in both countries may warrant particular consideration, given the similarities in their regulatory systems, patients and clinical practice patterns, and market sizes. Since 2003, the US-Japan Harmonization By Doing (HBD) initiative has been focused on identifying and addressing clinical and regulatory barriers to medical devices access in both countries via collaboration between governmental, academic, and industry stakeholders. Through the efforts of HBD participants, US-Japanese clinical trials have been conducted and the resulting data have supported regulatory approval for marketing in both countries. Based on these experiences, this paper outlines some of the key factors to consider when developing a global clinical trial involving US and Japanese participation. These considerations include the mechanisms for consultation with regulatory authorities on clinical trial strategies, the regulatory framework for clinical trial notification and approval, recruitment and conduct of clinical sites, and lessons learned from specific US-Japanese clinical trial experiences. The goal of this paper is to promote global access to promising medical technologies by assisting potential clinical trial sponsors in understanding when an international strategy may be appropriate and successful.


Subject(s)
Device Approval , Humans , United States , Japan
14.
J Biol Chem ; 286(37): 32697-704, 2011 Sep 16.
Article in English | MEDLINE | ID: mdl-21719696

ABSTRACT

Derivation of patient-specific induced pluripotent stem cells (iPSCs) opens a new avenue for future applications of regenerative medicine. However, before iPSCs can be used in a clinical setting, it is critical to validate their in vivo fate following autologous transplantation. Thus far, preclinical studies have been limited to small animals and have yet to be conducted in large animals that are physiologically more similar to humans. In this study, we report the first autologous transplantation of iPSCs in a large animal model through the generation of canine iPSCs (ciPSCs) from the canine adipose stromal cells and canine fibroblasts of adult mongrel dogs. We confirmed pluripotency of ciPSCs using the following techniques: (i) immunostaining and quantitative PCR for the presence of pluripotent and germ layer-specific markers in differentiated ciPSCs; (ii) microarray analysis that demonstrates similar gene expression profiles between ciPSCs and canine embryonic stem cells; (iii) teratoma formation assays; and (iv) karyotyping for genomic stability. Fate of ciPSCs autologously transplanted to the canine heart was tracked in vivo using clinical positron emission tomography, computed tomography, and magnetic resonance imaging. To demonstrate clinical potential of ciPSCs to treat models of injury, we generated endothelial cells (ciPSC-ECs) and used these cells to treat immunodeficient murine models of myocardial infarction and hindlimb ischemia.


Subject(s)
Adipose Tissue/metabolism , Gene Expression Regulation , Induced Pluripotent Stem Cells/metabolism , Stem Cell Transplantation , Adipose Tissue/cytology , Animals , Disease Models, Animal , Dogs , Embryonic Stem Cells/cytology , Embryonic Stem Cells/metabolism , Gene Expression Profiling , Humans , Induced Pluripotent Stem Cells/cytology , Male , Mice , Mice, SCID , Myocardial Ischemia/therapy , Oligonucleotide Array Sequence Analysis , Stromal Cells/cytology , Stromal Cells/metabolism , Transplantation, Autologous , Transplantation, Heterologous
15.
N Engl J Med ; 360(3): 213-24, 2009 Jan 15.
Article in English | MEDLINE | ID: mdl-19144937

ABSTRACT

BACKGROUND: In patients with multivessel coronary artery disease who are undergoing percutaneous coronary intervention (PCI), coronary angiography is the standard method for guiding the placement of the stent. It is unclear whether routine measurement of fractional flow reserve (FFR; the ratio of maximal blood flow in a stenotic artery to normal maximal flow), in addition to angiography, improves outcomes. METHODS: In 20 medical centers in the United States and Europe, we randomly assigned 1005 patients with multivessel coronary artery disease to undergo PCI with implantation of drug-eluting stents guided by angiography alone or guided by FFR measurements in addition to angiography. Before randomization, lesions requiring PCI were identified on the basis of their angiographic appearance. Patients assigned to angiography-guided PCI underwent stenting of all indicated lesions, whereas those assigned to FFR-guided PCI underwent stenting of indicated lesions only if the FFR was 0.80 or less. The primary end point was the rate of death, nonfatal myocardial infarction, and repeat revascularization at 1 year. RESULTS: The mean (+/-SD) number of indicated lesions per patient was 2.7+/-0.9 in the angiography group and 2.8+/-1.0 in the FFR group (P=0.34). The number of stents used per patient was 2.7+/-1.2 and 1.9+/-1.3, respectively (P<0.001). The 1-year event rate was 18.3% (91 patients) in the angiography group and 13.2% (67 patients) in the FFR group (P=0.02). Seventy-eight percent of the patients in the angiography group were free from angina at 1 year, as compared with 81% of patients in the FFR group (P=0.20). CONCLUSIONS: Routine measurement of FFR in patients with multivessel coronary artery disease who are undergoing PCI with drug-eluting stents significantly reduces the rate of the composite end point of death, nonfatal myocardial infarction, and repeat revascularization at 1 year. (ClinicalTrials.gov number, NCT00267774.)


Subject(s)
Angioplasty, Balloon, Coronary/methods , Coronary Angiography , Coronary Artery Disease/therapy , Drug-Eluting Stents , Fractional Flow Reserve, Myocardial , Aged , Angioplasty, Balloon, Coronary/economics , Coronary Angiography/economics , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/mortality , Coronary Restenosis/prevention & control , Female , Follow-Up Studies , Health Care Costs , Humans , Kaplan-Meier Estimate , Length of Stay , Male , Middle Aged , Myocardial Infarction/epidemiology , Retreatment/statistics & numerical data , Stents
16.
Cardiovasc Revasc Med ; 37: 112-117, 2022 04.
Article in English | MEDLINE | ID: mdl-34607786

ABSTRACT

Effective treatment strategies and medical devices continue to be needed in Japan and the United States of America (US) to mitigate the growing burden of cardiovascular disease and coronary heart disease. Unfortunately, there can be a delay in gaining cardiovascular device approval in Japan after a device has already been approved and is in use in the US. The Harmonization by Doing (HBD) program; however, can eliminate this delay and reduce the cost of completing a clinical trial in Japan. The HBD proof-of-concept study, COAST, resulted in approval of the Diamondback 360® Coronary Orbital Atherectomy System Micro Crown simultaneously in Japan and the US on the same day. Subsequently, the Diamondback 360® Coronary OAS Classic Crown also received approval in Japan. The COAST study provides further evidence that global clinical trials via HBD for medical devices are practical and advantageous.


Subject(s)
Atherectomy, Coronary , Coronary Artery Disease , Percutaneous Coronary Intervention , Vascular Calcification , Atherectomy , Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/surgery , Humans , Japan , Severity of Illness Index , Treatment Outcome , United States , Vascular Calcification/diagnostic imaging , Vascular Calcification/therapy
17.
Epidemiol Health ; 44: e2022080, 2022.
Article in English | MEDLINE | ID: mdl-36177978

ABSTRACT

OBJECTIVES: Using a dataset from a survey on national health and productivity management, we identified health and productivity factors associated with organizational profitability. METHODS: The Ministry of Economy, Trade and Industry conducted an annual survey on Health and Productivity Management between 2014 and 2021. We assessed the associations of organizational health and productivity management using survey questions collected in 2017 and 2018, with the rate of change in profits from 2017 and 2018 to 2020. We identified factors associated with organizational profitability using eXtreme Gradient Boosting, and calculated SHapley Additive exPlanation (SHAP) values for each factor. RESULTS: Among 1,593 companies (n= 4,359,834 employees), the mean age of employees at baseline was 40.3 years and the proportion of women was 25.8%. A confusion matrix for evaluating model performance had an accuracy of 0.997, precision of 0.993, recall of 0.997, and area under the precision-recall curve of 0.999. The most important factors related to an increase in corporate profits were the percentage of current smokers (SHAP value, 0.121), per-employee cost of health services (0.084) and medical services (0.050); the percentage of full-time employees working in sales departments (0.074) and distribution or customer service departments (0.054); the percentage of employees who slept well (0.055); and the percentage of employees within a company who regularly exercised (0.043). CONCLUSIONS: Employees' lifestyle-related health risk factors and organizations' management systems were associated with organizational profitability. Lifestyle medicine professionals may demonstrate a significant return on investment by creating a healthier and more productive workforce.


Subject(s)
Industry , Occupational Health , Humans , Female , Adult , Japan , Life Style , Commerce
18.
Circulation ; 122(11 Suppl): S170-8, 2010 Sep 14.
Article in English | MEDLINE | ID: mdl-20837910

ABSTRACT

BACKGROUND: ε protein kinase C (εPKC) is involved in vascular smooth muscle cell (VSMC) activation, but little is known about its function in vascular pathology. We aimed at assessing the role of εPKC in the development of restenosis. METHODS AND RESULTS: Rat models of aortic balloon injury with or without subsequent stenting were used. Rats were treated with the selective ψεPKC activator ε receptor for activated protein kinase C (ψεRACK), the selective εPKC inhibitor εV1-2, or saline. Both down-stream cascades of the platelet-derived growth factor receptor via extracellular signal-regulated kinase and Akt, respectively, were evaluated in vivo and in VSMC cultures. Intimal hyperplasia with luminal obliteration developed in saline-treated balloon-injured rat aortas (20.3±8.0%), and ψεRACK significantly promoted neointima development (32.4±4.9%, P=0.033), whereas εV1-2 significantly inhibited luminal narrowing (9.2±4.3%, P=0.039). εPKC inhibition led to significantly reduced VSMC extracellular signal-regulated kinase phosphorylation in vivo, whereas Akt phosphorylation was not markedly affected. Neointimal proliferation in vivo and platelet-derived growth factor-induced VSMC proliferation/migration in vitro were significantly inhibited by εV1-2. The inhibition of the platelet-derived growth factor pathway was mediated by inhibiting down-stream extracellular signal-regulated kinase and Akt phosphorylation. In vitro, εV1-2 showed inhibitory properties on endothelial cell proliferation, but that did not prevent reendothelialization in vivo. εV1-2 showed proapoptotic effects on VSMC in vitro. After stent implantation, luminal restenosis (quantified by optical coherence tomography imaging) was significantly reduced with εV1-2 (8.0±2.0%) compared with saline (20.2±9.8%, P=0.028). CONCLUSIONS: εPKC seems to be centrally involved in the development of neointimal hyperplasia. We suggest that εPKC inhibition may be mediated via inhibition of extracellular signal-regulated kinase and Akt activation. εPKC modulation may become a new therapeutic target against vascular restenosis.


Subject(s)
Aorta , Endothelial Cells/enzymology , Graft Occlusion, Vascular , Myocytes, Smooth Muscle/enzymology , Protein Kinase C-epsilon , Protein Kinase Inhibitors/pharmacology , Animals , Aorta/enzymology , Aorta/injuries , Apoptosis/drug effects , Cell Movement/drug effects , Cell Proliferation , Cells, Cultured , Coculture Techniques , Enzyme Activation/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Graft Occlusion, Vascular/enzymology , Humans , Male , Phosphorylation/drug effects , Platelet-Derived Growth Factor/metabolism , Protein Kinase C-epsilon/antagonists & inhibitors , Protein Kinase C-epsilon/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley
19.
J Biomed Biotechnol ; 2011: 195483, 2011.
Article in English | MEDLINE | ID: mdl-21253493

ABSTRACT

To improve human health, scientific discoveries must be translated into practical applications. Inherent in the development of these technologies is the role of preclinical testing using animal models. Although significant insight into the molecular and cellular basis has come from small animal models, significant differences exist with regard to cardiovascular characteristics between these models and humans. Therefore, large animal models are essential to develop the discoveries from murine models into clinical therapies and interventions. This paper will provide an overview of the more frequently used large animal models, especially porcine models for preclinical studies.


Subject(s)
Cardiovascular Diseases/pathology , Disease Models, Animal , Sus scrofa , Animals , Coronary Vessels/pathology , Humans , Myocardial Ischemia/pathology
20.
Circ J ; 74(6): 1257-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20453394

ABSTRACT

BACKGROUND: Although peri-strut low-intensity area (PLIA) is frequently observed on post-stenting optical coherence tomography (OCT) images, the histology associated with PLIA is undocumented. METHODS AND RESULTS: The 36 porcine coronary lesions treated with bare-metal (BMS: n=16) or drug-eluting (DES: n=20) stents were assessed by OCT and histology at 28 days. DES showed a significantly higher incidence of PLIA than BMS. Also, +PLIA stents had greater neointima than PLIA stents. Histological analysis revealed the existence of fibrinoid and proteoglycans at the site of PLIA. CONCLUSIONS: PLIA might be represented by the presence of fibrinoid and proteoglycans, and associated with neointimal proliferation after stenting.


Subject(s)
Coronary Vessels/pathology , Stents/adverse effects , Tomography, Optical Coherence/methods , Tunica Intima/pathology , Animals , Cell Proliferation , Coronary Vessels/surgery , Drug-Eluting Stents/adverse effects , Fibrin/analysis , Metals , Proteoglycans/analysis , Swine , Treatment Outcome
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