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Zhu P, Simon I, Kokalari I, Kohane DS, Rwei AY. Miniaturized therapeutic systems for ultrasound-modulated drug delivery to the central and peripheral nervous system. Adv Drug Deliv Rev 2024; 208:115275. [PMID: 38442747 PMCID: PMC11031353 DOI: 10.1016/j.addr.2024.115275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 02/19/2024] [Accepted: 03/01/2024] [Indexed: 03/07/2024]
Abstract
Ultrasound is a promising technology to address challenges in drug delivery, including limited drug penetration across physiological barriers and ineffective targeting. Here we provide an overview of the significant advances made in recent years in overcoming technical and pharmacological barriers using ultrasound-assisted drug delivery to the central and peripheral nervous system. We commence by exploring the fundamental principles of ultrasound physics and its interaction with tissue. The mechanisms of ultrasonic-enhanced drug delivery are examined, as well as the relevant tissue barriers. We highlight drug transport through such tissue barriers utilizing insonation alone, in combination with ultrasound contrast agents (e.g., microbubbles), and through innovative particulate drug delivery systems. Furthermore, we review advances in systems and devices for providing therapeutic ultrasound, as their practicality and accessibility are crucial for clinical application.
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Affiliation(s)
- Pancheng Zhu
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ, Delft, the Netherlands; State Key Laboratory of Mechanics and Control of Aerospace Structures, Nanjing University of Aeronautics & Astronautics, 210016, Nanjing, China; Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Ignasi Simon
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Ida Kokalari
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ, Delft, the Netherlands
| | - Daniel S Kohane
- Laboratory for Biomaterials and Drug Delivery, Department of Anesthesiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Alina Y Rwei
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ, Delft, the Netherlands.
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2
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Fan P, Fan H, Wang S. From emerging modalities to advanced applications of hydrogel piezoelectrics based on chitosan, gelatin and related biological macromolecules: A review. Int J Biol Macromol 2024; 262:129691. [PMID: 38272406 DOI: 10.1016/j.ijbiomac.2024.129691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/29/2023] [Accepted: 01/21/2024] [Indexed: 01/27/2024]
Abstract
The rapid development of functional materials and manufacturing technologies is fostering advances in piezoelectric materials (PEMs). PEMs can convert mechanical energy into electrical energy. Unlike traditional power sources, which need to be replaced and are inconvenient to carry, PEMs have extensive potential applications in smart wearable and implantable devices. However, the application of conventional PEMs is limited by their poor flexibility, low ductility, and susceptibility to fatigue failure. Incorporating hydrogels, which are flexible, stretchable, and self-healing, providing a way to overcome these limitations of PEMs. Hydrogel-based piezoelectric materials (H-PEMs) not only resolve the shortcomings of traditional PEMs but also provide biocompatibility and more promising application potential. This paper summarizes the working principle of H-PEMs. Recent advances in the use of H-PEMs as sensors and in vitro energy harvesting devices for smart wearable devices are described in detail, with emphasis on application scenarios in human body like fingers, wrists, ankles, and feet. In addition, the recent progress of H-PEMs in implantable medical devices, especially the potential applications in human body parts such as bones, skin, and heart, are also elaborated. In addition, challenges and potential improvements in H-PEMs are discussed.
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Affiliation(s)
- Peng Fan
- School of Materials and Chemistry, University of Shanghai for Science and Technology, No. 516 Jungong Road, Shanghai 200093, PR China
| | - Hengwei Fan
- Department of Hepatic Surgery Dept I, the Eastern Hepatobiliary Surgery Hospital, Navy Medical University, No. 225 Changhai Road, Shanghai 200438, PR China.
| | - Shige Wang
- School of Materials and Chemistry, University of Shanghai for Science and Technology, No. 516 Jungong Road, Shanghai 200093, PR China; Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR 999077, PR China.
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3
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Abdelnabi D, Lastakchi S, Watts C, Atkins H, Hingtgen S, Valdivia A, McConville C. Local administration of irinotecan using an implantable drug delivery device stops high-grade glioma tumor recurrence in a glioblastoma tumor model. Drug Deliv Transl Res 2024:10.1007/s13346-024-01524-x. [PMID: 38319555 DOI: 10.1007/s13346-024-01524-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2024] [Indexed: 02/07/2024]
Abstract
The treatment for Glioblastoma is limited due to the presence of the blood brain barrier, which restricts the entry of chemotherapeutic drugs into the brain. Local delivery into the tumor resection margin has the potential to improve efficacy of chemotherapy. We developed a safe and clinically translatable irinotecan implant for local delivery to increase its efficacy while minimizing systemic side effects. Irinotecan-loaded implants were manufactured using hot melt extrusion, gamma sterilized at 25 kGy, and characterized for their irinotecan content, release, and drug diffusion. Their therapeutic efficacy was evaluated in a patient-derived xenograft mouse resection model of glioblastoma. Their safety and translatability were evaluated using histological analysis of brain tissue and serum chemistry analysis. Implants containing 30% and 40% w/w irinotecan were manufactured without plasticizer. The 30% and 40% implants showed moderate local toxicity up to 2- and 6-day post-implantation. Histopathology of the implantation site showed signs of necrosis at days 45 and 14 for the 30% and 40% implants. Hematological analysis and clinical chemistry showed no signs of serious systemic toxicity for either implant. The 30% implants had an 80% survival at day 148, with no sign of tumor recurrence. Gamma sterilization and 12-month storage had no impact on the integrity of the 30% implants. This study demonstrates that the 30% implants are a promising novel treatment for glioblastoma that could be quickly translated into the clinic.
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Affiliation(s)
- Dina Abdelnabi
- School of Pharmacy, Robert Aitken Institute for Clinical Research, Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - Sarah Lastakchi
- School of Pharmacy, Robert Aitken Institute for Clinical Research, Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - Colin Watts
- Department of Neurosurgery, University Hospitals Birmingham, NHS Foundation Trust, Birmingham, UK
| | - Hannah Atkins
- Department of Pathology and Laboratory Medicine, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Shawn Hingtgen
- Division of Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Alain Valdivia
- Division of Molecular Pharmaceutics, UNC Eshelman School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Christopher McConville
- School of Pharmacy, Robert Aitken Institute for Clinical Research, Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, B15 2TT, UK.
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4
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Wallner AL, Savona S, Kahwash R. Cardiac Contractility Modulation: Implications in Heart Failure, a Current Review. Heart Fail Clin 2024; 20:51-60. [PMID: 37953021 DOI: 10.1016/j.hfc.2023.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
Cardiac contractility modulation (CCM) is a novel therapeutic approach for heart failure patients, which utilizes nonexcitatory electrical myocardial stimulation in the absolute refractory period of the cardiac cycle. This stimulation has been shown to increase contractility, leading to improved heart failure symptoms, functional status, and quality of life. CCM is FDA approved for heart failure patients with an LVEF between 25% and 45% who remained symptomatic despite optimal medical therapy and not candidate of cardiac resynchronization therapy. CCM offers expanded treatment options for heart failure patients who have continued symptoms while on optimal medical therapy.
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Affiliation(s)
- Alexander L Wallner
- Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Salvatore Savona
- Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Rami Kahwash
- Division of Cardiovascular Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
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Molina-Peña R, Ferreira NH, Roy C, Roncali L, Najberg M, Avril S, Zarur M, Bourgeois W, Ferreirós A, Lucchi C, Cavallieri F, Hindré F, Tosi G, Biagini G, Valzania F, Berger F, Abal M, Rousseau A, Boury F, Alvarez-Lorenzo C, Garcion E. Implantable SDF-1α-loaded silk fibroin hyaluronic acid aerogel sponges as an instructive component of the glioblastoma ecosystem: Between chemoattraction and tumor shaping into resection cavities. Acta Biomater 2024; 173:261-282. [PMID: 37866725 DOI: 10.1016/j.actbio.2023.10.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 10/24/2023]
Abstract
In view of inevitable recurrences despite resection, glioblastoma (GB) is still an unmet clinical need. Dealing with the stromal-cell derived factor 1-alpha (SDF-1α)/CXCR4 axis as a hallmark of infiltrative GB tumors and with the resection cavity situation, the present study described the effects and relevance of a new engineered micro-nanostructured SF-HA-Hep aerogel sponges, made of silk fibroin (SF), hyaluronic acid (HA) and heparin (Hep) and loaded with SDF-1α, to interfere with the GB ecosystem and residual GB cells, attracting and confining them in a controlled area before elimination. 70 µm-pore sponges were designed as an implantable scaffold to trap GB cells. They presented shape memory and fit brain cavities. Histological results after implantation in brain immunocompetent Fischer rats revealed that SF-HA-Hep sponges are well tolerated for more than 3 months while moderately and reversibly colonized by immuno-inflammatory cells. The use of human U87MG GB cells overexpressing the CXCR4 receptor (U87MG-CXCR4+) and responding to SDF-1α allowed demonstrating directional GB cell attraction and colonization of the device in vitro and in vivo in orthotopic resection cavities in Nude rats. Not modifying global survival, aerogel sponge implantation strongly shaped U87MG-CXCR4+ tumors in cavities in contrast to random infiltrative growth in controls. Overall, those results support the interest of SF-HA-Hep sponges as modifiers of the GB ecosystem dynamics acting as "cell meeting rooms" and biocompatible niches whose properties deserve to be considered toward the development of new clinical procedures. STATEMENT OF SIGNIFICANCE: Brain tumor glioblastoma (GB) is one of the worst unmet clinical needs. To prevent the relapse in the resection cavity situation, new implantable biopolymer aerogel sponges loaded with a chemoattractant molecule were designed and preclinically tested as a prototype targeting the interaction between the initial tumor location and its attraction by the peritumoral environment. While not modifying global survival, biocompatible SDF1-loaded hyaluronic acid and silk fibroin sponges induce directional GB cell attraction and colonization in vitro and in rats in vivo. Interestingly, they strongly shaped GB tumors in contrast to random infiltrative growth in controls. These results provide original findings on application of exogenous engineered niches that shape tumors and serve as cell meeting rooms for further clinical developments.
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Affiliation(s)
- Rodolfo Molina-Peña
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | | | - Charlotte Roy
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | - Loris Roncali
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | - Mathie Najberg
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | - Sylvie Avril
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | - Mariana Zarur
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, ID Farma (GI-1645), Facultad de Farmacia, iMATUS, and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - William Bourgeois
- Inserm UMR1205, Brain Tech Lab, Grenoble Alpes University Hospital (CHUGA), Grenoble, 38000, France
| | - Alba Ferreirós
- NASASBIOTECH S.L., Cantón Grande nº 9, 15003, A Coruña, Spain
| | - Chiara Lucchi
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Francesco Cavallieri
- Neurology Unit, Neuromotor and Rehabilitation Department, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
| | - François Hindré
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | - Giovani Tosi
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Giuseppe Biagini
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Franco Valzania
- Neurology Unit, Neuromotor and Rehabilitation Department, Azienda USL-IRCCS di Reggio Emilia, Reggio Emilia, Italy
| | - François Berger
- Inserm UMR1205, Brain Tech Lab, Grenoble Alpes University Hospital (CHUGA), Grenoble, 38000, France
| | - Miguel Abal
- NASASBIOTECH S.L., Cantón Grande nº 9, 15003, A Coruña, Spain
| | - Audrey Rousseau
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | - Frank Boury
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France
| | - Carmen Alvarez-Lorenzo
- Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, ID Farma (GI-1645), Facultad de Farmacia, iMATUS, and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Emmanuel Garcion
- Univ Angers, Nantes Université, Inserm, CNRS, CRCI2NA, SFR ICAT, F-49000 Angers, France.
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Senderovich N, Shah S, Ow TJ, Rand S, Nosanchuk J, Wake N. Assessment of Staphylococcus Aureus growth on biocompatible 3D printed materials. 3D Print Med 2023; 9:30. [PMID: 37914942 PMCID: PMC10621153 DOI: 10.1186/s41205-023-00195-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 10/16/2023] [Indexed: 11/03/2023] Open
Abstract
The customizability of 3D printing allows for the manufacturing of personalized medical devices such as laryngectomy tubes, but it is vital to establish the biocompatibility of printing materials to ensure that they are safe and durable. The goal of this study was to assess the presence of S. aureus biofilms on a variety of 3D printed materials (two surgical guide resins, a photopolymer, an elastomer, and a thermoplastic elastomer filament) as compared to standard, commercially available laryngectomy tubes.C-shaped discs (15 mm in height, 20 mm in diameter, and 3 mm in thickness) were printed with five different biocompatible 3D printing materials and S. aureus growth was compared to Shiley™ laryngectomy tubes made from polyvinyl chloride. Discs of each material were inoculated with S. aureus cultures and incubated overnight. All materials were then removed from solution, washed in phosphate-buffered saline to remove planktonic bacteria, and sonicated to detach biofilms. Some solution from each disc was plated and colony-forming units were manually counted the following day. The resulting data was analyzed using a Kruskal-Wallis and Wilcoxon Rank Sum test to determine pairwise significance between the laryngectomy tube material and the 3D printed materials.The Shiley™ tube grew a median of 320 colonies (IQR 140-520), one surgical guide resin grew a median of 640 colonies (IQR 356-920), the photopolymer grew a median of 340 colonies (IQR 95.5-739), the other surgical guide resin grew a median of 431 colonies (IQR 266.5-735), the thermoplastic elastomer filament grew a median of 188 colonies (IQR 113.5-335), and the elastomer grew a median of 478 colonies (IQR 271-630). Using the Wilcoxon Rank Sum test, manual quantification showed a significant difference between biofilm formation only between the Shiley™ tube and a surgical guide resin (p = 0.018).This preliminary study demonstrates that bacterial colonization was comparable among most 3D printed materials as compared to the conventionally manufactured device. Continuation of this work with increased replicates will be necessary to determine which 3D printing materials optimally resist biofilm formation.
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Affiliation(s)
- Nicole Senderovich
- Albert Einstein College of Medicine, Montefiore Health System, Bronx, NY, USA.
| | - Sharan Shah
- Department of Otorhinolaryngology - Head and Neck Surgery, Montefiore Health System, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Thomas J Ow
- Department of Otorhinolaryngology - Head and Neck Surgery, Montefiore Health System, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Pathology, Montefiore Health System, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Stephanie Rand
- Department of Physical Medicine & Rehabilitation, Montefiore Health System, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Joshua Nosanchuk
- Department of Infectious Disease, Montefiore Health System, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Nicole Wake
- Department of Research and Scientific Affairs, GE HealthCare, New York, NY, USA
- Center for Advanced Imaging Innovation and Research (CAI²R) and Bernard and Irene, Schwartz Center for Biomedical Imaging, Department of Radiology, NYU Langone Health, NYU Grossman School of Medicine, New York, NY, USA
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7
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Chatterjee S, Joshi RK, Sakorikar T, Behera B, Bhaskar N, Kv SG, Jayachandra M, Pandya HJ. Design and fabrication of a microelectrode array for studying epileptiform discharges from rodents. Biomed Microdevices 2023; 25:31. [PMID: 37584876 DOI: 10.1007/s10544-023-00672-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/10/2023] [Indexed: 08/17/2023]
Abstract
Local field potentials, the extracellular electrical activities from brain regions, provide clinically relevant information about the status of neurophysiological conditions, including epilepsy. In this study, a 13-channel silicon-based single-shank microelectrode array (MEA) was designed and fabricated to record local field potentials (LFPs) from the different depths of a rat's brain. A titanium/gold layer was patterned as electrodes on an oxidized silicon substrate, and silicon dioxide was deposited as a passivation layer. The fabricated array was implanted in the somatosensory cortex of the right hemisphere of an anesthetized rat. The developed MEA was interfaced with an OpenBCI Cyton Daisy Biosensing Board to acquire the local field potentials. The LFPs were acquired at three different neurophysiological conditions, including baseline signals, chemically-induced epileptiform discharges, and recovered baseline signals after anti-epileptic drug (AED) administration. Further, time-frequency analyses were performed on the acquired biopotentials to study the difference in spatiotemporal features. The processed signals and time-frequency analyses clearly distinguish between pre-convulsant and post-AED baselines and evoked epileptiform discharges.
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Affiliation(s)
- Suman Chatterjee
- Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - Rathin K Joshi
- Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - Tushar Sakorikar
- Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - Bhagaban Behera
- Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - Nitu Bhaskar
- Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
| | - Shabari Girishan Kv
- Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India
- MS Ramaiah Memorial Hospital, Bangalore, India
| | - Mahesh Jayachandra
- Center for BioSystems Science and Engineering, Indian Institute of Science, Bangalore, India
| | - Hardik J Pandya
- Department of Electronic Systems Engineering, Indian Institute of Science, Bangalore, India.
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Oh J, Kim J, Moon S, Lee Y, Park D, Joo J, Shon YM, Park SM, Jeong U. Subcutaneous mechano-electrocardiogram (MECG) sensor for complementary cardiac diagnosis. Biosens Bioelectron 2023; 236:115443. [PMID: 37276637 DOI: 10.1016/j.bios.2023.115443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/30/2023] [Accepted: 05/30/2023] [Indexed: 06/07/2023]
Abstract
Since the heart pumps out the blood through the excitation-contraction coupling, simultaneous monitoring of the electrical and mechanical characteristics is beneficial for comprehensive diagnosis of cardiac disorders. Currently, these characteristics are monitored separately with electrocardiogram (ECG) and medical imaging techniques. This work presents a fully implantable device named mechano-electrocardiogram (MECG) sensor that can measure mechanocardiogram (MCG) and ECG together. The key to the success is fabrication of permeable electrodes on a single low-modulus porous nanofiber mat, which helps immediate adhesion of the sensor on the tissue. A strain-insensitive electrode is used as the ECG electrode and a strain-sensitive electrode is used for MCG. The MECG device is implanted subcutaneously in the skin above the heart of the rat. Through a vasopressor (phenylephrine) injection test, the MECG signals indicate that the MCG amplitude is related with blood pressure and the ECG peak interval is more related with heart rate. These results confirm that the MECG device is clinically meaningful for continuous and comprehensive monitoring of the electrical and mechanical characteristics of the heart.
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Affiliation(s)
- Joosung Oh
- Department of Materials Science and Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, South Korea
| | - Junho Kim
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, South Korea
| | - Sungmin Moon
- Department of Materials Science and Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, South Korea
| | - YoungHyun Lee
- Department of Materials Science and Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, South Korea
| | - Daejong Park
- Department of Convergernce IT Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, South Korea
| | - Jaesoon Joo
- Biomedical Engineering Research Center, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, 06531, South Korea
| | - Young-Min Shon
- Biomedical Engineering Research Center, Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul, 06531, South Korea
| | - Sung-Min Park
- Department of Convergernce IT Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, South Korea.
| | - Unyong Jeong
- Department of Materials Science and Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, 37673, South Korea.
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9
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Chatterjee S, Sakorikar T, Bs A, Joshi RK, Sikaria A, Jayachandra M, V V, Pandya HJ. A flexible implantable microelectrode array for recording electrocorticography signals from rodents. Biomed Microdevices 2022; 24:31. [PMID: 36138255 DOI: 10.1007/s10544-022-00632-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2022] [Indexed: 11/27/2022]
Abstract
Electrocorticography signals, the intracranial recording of electrical signatures of the brain, are recorded by non-penetrating planar electrode arrays placed on the cortical surface. Flexible electrode arrays minimize the tissue damage upon implantation. This work shows the design and development of a 32-channel flexible microelectrode array to record electrocorticography signals from the rat's brain. The array was fabricated on a biocompatible flexible polyimide substrate. A titanium/gold layer was patterned as electrodes, and a thin polyimide layer was used for insulation. The fabricated microelectrode array was mounted on the exposed somatosensory cortex of the right hemisphere of a rat after craniotomy and incision of the dura. The signals were recorded using OpenBCI Cyton Daisy Biosensing Boards. The array faithfully recorded the baseline electrocorticography signals, the induced epileptic activities after applying a convulsant, and the recovered baseline signals after applying an antiepileptic drug. The signals recorded by such fabricated microelectrode array from anesthetized rats demonstrate its potential to monitor electrical signatures corresponding to epilepsy. Finally, the time-frequency analyses highlight the difference in spatiotemporal features of baseline and evoked epileptic discharges.
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10
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Kim H, Lee SH, Wentworth A, Babaee S, Wong K, Collins JE, Chu J, Ishida K, Kuosmanen J, Jenkins J, Hess K, Lopes A, Morimoto J, Wan Q, Potdar SV, McNally R, Tov C, Kim NY, Hayward A, Wollin D, Langer R, Traverso G. Biodegradable ring-shaped implantable device for intravesical therapy of bladder disorders. Biomaterials 2022; 288:121703. [PMID: 36030104 PMCID: PMC10485746 DOI: 10.1016/j.biomaterials.2022.121703] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 07/22/2022] [Accepted: 07/24/2022] [Indexed: 11/26/2022]
Abstract
Intravesical instillation is an efficient drug delivery route for the local treatment of various urological conditions. Nevertheless, intravesical instillation is associated with several challenges, including pain, urological infection, and frequent clinic visits for catheterization; these difficulties support the need for a simple and easy intravesical drug delivery platform. Here, we propose a novel biodegradable intravesical device capable of long-term, local drug delivery without a retrieval procedure. The intravesical device is composed of drug encapsulating biodegradable polycaprolactone (PCL) microcapsules and connected by a bioabsorbable Polydioxanone (PDS) suture with NdFeB magnets in the end. The device is easily inserted into the bladder and forms a 'ring' shape optimized for maximal mechanical stability as informed by finite element analysis. In this study, inserted devices were retained in a swine model for 4 weeks. Using this device, we evaluated the system's capacity for delivery of lidocaine and resiquimod and demonstrated prolonged drug release. Moreover, a cost-effectiveness analysis supports device implementation compared to the standard of care. Our data support that this device can be a versatile drug delivery platform for urologic medications.
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Affiliation(s)
- Hyunjoon Kim
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Seung Ho Lee
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Adam Wentworth
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Sahab Babaee
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Kaitlyn Wong
- Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Joy E Collins
- Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Jacqueline Chu
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Division of Gastroenterology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA
| | - Keiko Ishida
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Johannes Kuosmanen
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Joshua Jenkins
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Kaitlyn Hess
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Aaron Lopes
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Joshua Morimoto
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Qianqian Wan
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Shaunak V Potdar
- Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Ronan McNally
- Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Caitlynn Tov
- Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Na Yoon Kim
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Alison Hayward
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA; Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Daniel Wollin
- Division of Urology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Robert Langer
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Giovanni Traverso
- The David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA; Division of Gastroenterology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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11
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Pavon AG, Porretta AP, Arangalage D, Domenichini G, Rutz T, Hugelshofer S, Pruvot E, Monney P, Pascale P, Schwitter J. Feasibility of adenosine stress cardiovascular magnetic resonance perfusion imaging in patients with MR-conditional transvenous permanent pacemakers and defibrillators. J Cardiovasc Magn Reson 2022; 24:9. [PMID: 35022037 PMCID: PMC8756706 DOI: 10.1186/s12968-021-00842-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/21/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The use of stress perfusion-cardiovascular magnetic resonance (CMR) imaging remains limited in patients with implantable devices. The primary goal of the study was to assess the safety, image quality, and the diagnostic value of stress perfusion-CMR in patients with MR-conditional transvenous permanent pacemakers (PPM) or implantable cardioverter-defibrillators (ICD). METHODS Consecutive patients with a transvenous PPM or ICD referred for adenosine stress-CMR were enrolled in this single-center longitudinal study. The CMR protocol was performed using a 1.5 T system according to current guidelines while all devices were put in MR-mode. Quality of cine, late-gadolinium-enhancement (LGE), and stress perfusion sequences were assessed. An ischemia burden of ≥ 1.5 segments was considered significant. We assessed the safety, image quality and the occurrence of interference of the magnetic field with the implantable device. In case of ischemia, we also assessed the correlation with the presence of significant coronary lesions on coronary angiography. RESULTS Among 3743 perfusion-CMR examinations, 66 patients had implantable devices (1.7%). Image quality proved diagnostic in 98% of cases. No device damage or malfunction was reported immediately and at 1 year. Fifty patients were continuously paced during CMR. Heart rate and systolic blood pressure remained unchanged during adenosine stress, while diastolic blood pressure decreased (p = 0.007). Six patients (9%) had an ischemia-positive stress CMR and significant coronary stenoses were confirmed by coronary angiography in all cases. CONCLUSION Stress perfusion-CMR is safe, allows reliable ischemia detection, and provides good diagnostic value.
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Affiliation(s)
- Anna Giulia Pavon
- Division of Cardiology, Cardiocentro Ticino Institute, Ente Ospedaliero Cantonale, Via Tesserete, 48, 6900 Lugano, Switzerland
| | - Alessandra Pia Porretta
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Dimitri Arangalage
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Cardiology Department, AP-HP, Bichat Hospital and Université de Paris, Paris, France
| | - Giulia Domenichini
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - Tobias Rutz
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Cardiac Magnetic Resonance Center of the CHUV (CRMC), Lausanne University Hospital, Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne (UniL), Lausanne, Switzerland
| | - Sarah Hugelshofer
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Cardiac Magnetic Resonance Center of the CHUV (CRMC), Lausanne University Hospital, Lausanne, Switzerland
| | - Etienne Pruvot
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne (UniL), Lausanne, Switzerland
| | - Pierre Monney
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Cardiac Magnetic Resonance Center of the CHUV (CRMC), Lausanne University Hospital, Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne (UniL), Lausanne, Switzerland
| | - Patrizio Pascale
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne (UniL), Lausanne, Switzerland
| | - Juerg Schwitter
- Cardiovascular Department, Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Cardiac Magnetic Resonance Center of the CHUV (CRMC), Lausanne University Hospital, Lausanne, Switzerland
- Faculty of Biology and Medicine, University of Lausanne (UniL), Lausanne, Switzerland
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12
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Tokuda T, Haruta M, Sasagawa K, Ohta J. CMOS-Based Neural Interface Device for Optogenetics. Adv Exp Med Biol 2021; 1293:585-600. [PMID: 33398844 DOI: 10.1007/978-981-15-8763-4_41] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Optical and electronic neural interface devices based on CMOS technology are presented. Concept, design strategy, and fabrication of the CMOS-based optoelectronic neural interface devices are described. The devices are based on a technology of implantable CMOS image sensor. To realize addressable local optical stimulation, blue light-emitting diode array chip was integrated on the implantable CMOS image sensors. Functional demonstrations of the devices are also presented. Optical stimulation capability was demonstrated in both in vitro and in vivo experiments. Further perspective including wireless device architecture is also presented.
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13
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Cao L, Qiu X, Jiao Q, Zhao P, Li J, Wei Y. Polysaccharides and proteins-based nanogenerator for energy harvesting and sensing: A review. Int J Biol Macromol 2021; 173:225-243. [PMID: 33484800 DOI: 10.1016/j.ijbiomac.2021.01.109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 10/22/2022]
Abstract
Nanogenerator is a promising energy harvesting device that can scavenge tiny mechanical energy from the surrounding environment, and then convert it into electricity. Natural bio-polymers are the potential candidates for the design of nanogenerators due to their excellent characteristics like piezoelectricity, triboelectricity, non-toxicity, biocompatibility and biodegradability. Especially, nanogenerators using bio-sourced polymers as the core raw materials are suitable for wearable and implantable devices. In this review, major advancements in the sensing field of nanogenerators based on natural polysaccharides and proteins (cellulose, chitosan, alginate, agarose, starch, lignin, silk fibroin, collagen, gelatin, keratin, peptide, M13 bacteriophage, β-cyclodextrin, spider silk, etc.) are summarized. Also, challenges in the improvement of electric output performance, flexibility, anti-humidity and energy management for natural polymers based-nanogenerators are proposed. In the future, they will be applied in daily life as an alternative for traditional power source after addressing issues mentioned above.
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Affiliation(s)
- Lilong Cao
- Department of Chemistry School of Science, Tianjin University, Tianjin 300354, China
| | - Xia Qiu
- Department of Chemistry School of Science, Tianjin University, Tianjin 300354, China
| | - Qin Jiao
- Department of Chemistry School of Science, Tianjin University, Tianjin 300354, China
| | - Pinyi Zhao
- Institute for Materials Discovery, University College London, 107 Roberts Building, London WC1E 7JE, United Kingdom; Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - Junjie Li
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300354, China.
| | - Yuping Wei
- Department of Chemistry School of Science, Tianjin University, Tianjin 300354, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300354, China.
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14
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Uwaezuoke OJ, Kumar P, Pillay V, Choonara YE. Fouling in ocular devices: implications for drug delivery, bioactive surface immobilization, and biomaterial design. Drug Deliv Transl Res 2021; 11:1903-23. [PMID: 33454927 DOI: 10.1007/s13346-020-00879-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2020] [Indexed: 10/22/2022]
Abstract
The last 30 years has seen a proliferation of research on protein-resistant biomaterials targeted at designing bio-inert surfaces, which are prerequisite for optimal performance of implantable devices that contact biological fluids and tissues. These efforts have only been able to yield minimal results, and hence, the ideal anti-fouling biomaterial has remained elusive. Some studies have yielded biomaterials with a reduced fouling index among which high molecular weight polyethylene glycols have remained dominant. Interestingly, the field of implantable ocular devices has not experienced an outflow of research in this area, possibly due to the assumption that biomaterials tested in other body fluids can be translated for application in the ocular space. Unfortunately, progression in the molecular understanding of many ocular conditions has brought to the fore the need for treatment options that necessitates the use of anti-fouling biomaterials. From the earliest implanted horsehair and silk seton for glaucoma drainage to the recent mini telescopes for sight recovery, this review provides a concise incursion into the gradual evolution of biomaterials for the design of implantable ocular devices as well as approaches used to overcome the challenges with fouling. The implication of fouling for drug delivery, the design of immune-responsive biomaterials, as well as advanced surface immobilization approaches to support the overall performance of implantable ocular devices are also reviewed.
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15
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Sohrabi C, Ahsan S, Briasoulis A, Androulakis E, Siasos G, Srinivasan NT, Papageorgiou N. Contemporary management of heart failure patients with reduced ejection fraction: the role of implantable devices and catheter ablation. Rev Cardiovasc Med 2021; 22:415-428. [PMID: 34258908 DOI: 10.31083/j.rcm2202047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/27/2021] [Accepted: 06/09/2021] [Indexed: 11/06/2022] Open
Abstract
Heart failure (HF) is a complex clinical syndrome characterised by significant morbidity and mortality worldwide. Evidence-based therapies for the management of HF include several well-established neurohormonal antagonists and antiarrhythmic drug therapy to mitigate the onset of cardiac arrhythmia. However, the degree of rate and rhythm control achieved is often suboptimal and mortality rates continue to remain high. Implantable cardioverter-defibrillators (ICDs), cardiac resynchronization (CRT), and combined (CRT-D) therapies have emerged as integral and rapidly expanding technologies in the management of select patients with heart failure with reduced ejection fraction (HFrEF). ICDs treat ventricular arrhythmia and are used as primary prophylaxis for sudden cardiac death, while CRT resynchronizes ventricular contraction to improve left ventricular systolic function. Left ventricular assist device therapy has also been shown to provide clinically meaningful survival benefits in patients with advanced HF, and His-bundle pacing has more recently emerged as a safe, viable, and promising pacing modality for patients with CRT indication. Catheter ablation is another important and well-established strategy for managing cardiac arrhythmia in HF, demonstrating superior efficacy when compared with antiarrhythmic drug therapy alone. In this article, we provide a comprehensive and in-depth evaluation of the role of implantable devices and catheter ablation in patients with HFrEF, outlining current applications, recent advances, and future directions in practice.
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Affiliation(s)
- Catrin Sohrabi
- Electrophysiology Department, Barts Heart Centre, St. Bartholomew's Hospital, EC1A 7BE London, UK
| | - Syed Ahsan
- Electrophysiology Department, Barts Heart Centre, St. Bartholomew's Hospital, EC1A 7BE London, UK
| | - Alexandros Briasoulis
- Medical School, National and Kapodistrian University of Athens, 10679 Athens, Greece.,Section of Heart Failure and Transplant Division of Cardiovascular Diseases, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA
| | - Emmanuel Androulakis
- Heart Imaging Centre, Royal Brompton & Harefield NHS Foundation Trust, SW3 6NR London, UK
| | - Gerasimos Siasos
- 3rd Department of Cardiology, "Sotiria" Hospital University of Athens Medical School, 11527 Athens, Greece
| | - Neil T Srinivasan
- Department of Cardiac Electrophysiology, Essex Cardiothoracic Centre, SS16 5NL Basildon, UK.,Circulatory Health Research Group, Medical Technology Research Centre, School of Medicine, Anglia Ruskin University, CM1 1SQ Chelmsford, UK
| | - Nikolaos Papageorgiou
- Electrophysiology Department, Barts Heart Centre, St. Bartholomew's Hospital, EC1A 7BE London, UK.,Institute of Cardiovascular Science, University College London, WC1E 6BT London, UK
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16
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Tostón NS, Migueláñez MM, Tornero LP, Martínez SDC, Santos-Briz A, Curto CR. Reticular telangiectatic erythema by breast implants. JPRAS Open 2020; 27:7-11. [PMID: 33294578 PMCID: PMC7695883 DOI: 10.1016/j.jpra.2020.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 10/28/2020] [Indexed: 11/26/2022] Open
Abstract
Reticular telangiectatic erythema is a benign dermatosis which has been described on patients with pacemakers, implantable devices or materials inserted in their body. Etiology of this entity hasn't been clarified since the first description in 1981 but it is suggested that physical or mechanical factors have to be involved. We present the second case of bilateral reticular telangiectatic erythema by breast implants described in the literature.
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Affiliation(s)
- N Segurado Tostón
- Department of Dermatology, University Hospital of Salamanca, Salamanca, Spain
| | - M Medina Migueláñez
- Department of Dermatology, University Hospital of Salamanca, Salamanca, Spain
| | - L Puebla Tornero
- Department of Dermatology, University Hospital of Salamanca, Salamanca, Spain
| | | | - A Santos-Briz
- Department of Dermatology, University Hospital of Salamanca, Salamanca, Spain
| | - C Román Curto
- Department of Dermatology, University Hospital of Salamanca, Salamanca, Spain
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17
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Luciano MG, Dombrowski SM, El-Khoury S, Yang J, Thyagaraj S, Qvarlander S, Khalid S, Suk I, Manbachi A, Loth F. Epidural Oscillating Cardiac-Gated Intracranial Implant Modulates Cerebral Blood Flow. Neurosurgery 2020; 87:1299-1310. [PMID: 32533835 PMCID: PMC7666905 DOI: 10.1093/neuros/nyaa188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 03/16/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND We have previously reported a method and device capable of manipulating ICP pulsatility while minimally effecting mean ICP. OBJECTIVE To test the hypothesis that different modulations of the intracranial pressure (ICP) pulse waveform will have a differential effect on cerebral blood flow (CBF). METHODS Using an epidural balloon catheter attached to a cardiac-gated oscillating pump, 13 canine subjects underwent ICP waveform manipulation comparing different sequences of oscillation in successive animals. The epidural balloon was implanted unilaterally superior to the Sylvian sulcus. Subjects underwent ICP pulse augmentation, reduction and inversion protocols, directly comparing time segments of system activation and deactivation. ICP and CBF were measured bilaterally along with systemic pressure and heart rate. CBF was measured using both thermal diffusion, and laser doppler probes. RESULTS The activation of the cardiac-gate balloon implant resulted in an ipsilateral/contralateral ICP pulse amplitude increase with augmentation (217%/202% respectively, P < .0005) and inversion (139%/120%, P < .0005). The observed changes associated with the ICP mean values were smaller, increasing with augmentation (23%/31%, P < .0001) while decreasing with inversion (7%/11%, P = .006/.0003) and reduction (4%/5%, P < .0005). CBF increase was observed for both inversion and reduction protocols (28%/7.4%, P < .0001/P = .006 and 2.4%/1.3%, P < .0001/P = .003), but not the augmentation protocol. The change in CBF was correlated with ICP pulse amplitude and systolic peak changes and not with change in mean ICP or systemic variables (heart rate, arterial blood pressure). CONCLUSION Cardiac-gated manipulation of ICP pulsatility allows the study of intracranial pulsatile dynamics and provides a potential means of altering CBF.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Amir Manbachi
- Correspondence: Mark G. Luciano, MD, PhD, Departments of Neurosurgery and Biomedical Engineering, Johns Hopkins University, 600 North Wolfe Street, Phipps 126, Baltimore, MD 20287, USA.
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18
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Cappannoli L, Scacciavillani R, Rocco E, Perna F, Narducci ML, Vaccarella M, D'Amario D, Pelargonio G, Massetti M, Crea F, Aspromonte N. Cardiac contractility modulation for patient with refractory heart failure: an updated evidence-based review. Heart Fail Rev 2021; 26:227-35. [PMID: 32974722 DOI: 10.1007/s10741-020-10030-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/16/2020] [Indexed: 10/23/2022]
Abstract
Heart failure is the cardiovascular epidemic of the twenty-first century, with poor prognosis and quality of life despite optimized medical treatment. Despite over the last decade significant improvements, with a major impact on morbidity and mortality, have been made in therapy for heart failure with reduced ejection fraction, little progress was made in the development of devices, with the implantable defibrillator indicated for patients with left ventricle ejection fraction ≤ 35% and cardiac resynchronization therapy for those with QRS ≥ 130 ms and evidence of left bundle branch block. Nevertheless, only a third of patients meet these criteria and a high percentage of patients are non-responders in terms of improving symptoms. Nowadays, in patients with symptomatic heart failure with ejection fraction between 25% and 45% and QRS < 130 ms, not eligible for cardiac resynchronization, the cardiac contractility modulation (CCM) represents a concrete therapeutic option, having proved to be safe and effective in reducing hospitalizations for heart failure and improving symptoms, functional capacity, and quality of life. The aim of this review is therefore to summarize the pathophysiological mechanisms, the current indications, and the recent developments regarding the new applications of the CCM for patients with chronic heart failure.
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19
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Kelly SE, Clifford TJ, Coyle D, Martin J, Welch V, Skidmore B, Birnie D, Parkash R, Tang ASL, Wells GA. Virtual follow-up and care for patients with cardiac electronic implantable devices: protocol for a systematic review. Syst Rev 2020; 9:153. [PMID: 32593307 PMCID: PMC7321546 DOI: 10.1186/s13643-020-01406-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 06/07/2020] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Capacity to deliver outpatient care for patients with cardiac implantable electronic devices (CIEDs) may soon be outweighed by need. This systematic review aims to investigate the comparative effectiveness, safety, and cost for virtual or remote clinic interventions for patients with CIEDs and explores how outcomes may be influenced by patient or system factors in-depth. METHODS We will perform a systematic literature search in MEDLINE, Embase, PsycINFO, CINAHL, Proquest Dissertations & Theses, other EBM Reviews, and trial registry databases. Two authors will independently screen titles and abstracts for eligibility. We will include randomized and non-randomized controlled trials, quasi-randomized and experimental studies, cohort, and case-control studies. Study populations of interest are individuals with a CIED (pacemaker, ICD, CRT). Eligibility will be restricted to virtual or remote follow-up or care interventions compared to any other approach. The co-primary outcomes of interest are mortality and patient satisfaction. Secondary outcomes include clinical effectiveness (e.g., ICD shock, time-to-detection of medical event, hospitalizations), safety (e.g., serious or device-related adverse events), device efficacy (e.g., transmissions, malfunctions), costs, workflow (e.g., resources, process outcomes, time-saved), and patient reported (e.g., burden, quality of life). Data will be extracted by one author and checked by a second using a standardized template. We will use published frameworks to capture data relevant to intervention effects that may be influenced by intervention definition or complexity, context and setting, or in socially disadvantaged populations. Detailed descriptive results will be presented for all included studies and outcomes, and where feasible, synthesized using meta-analysis. Risk of bias will be assessed by two review authors independently using Cochrane Risk of Bias tools. Certainty of evidence will be assessed using the GRADE approach. DISCUSSION Increases in number of CIEDs implanted, combined with an aging population and finite health resource allocations at the system-level may lead to increased reliance on virtual follow-up or care models in the future. These models must prioritize consistent, equitable, and timely care as a priority. Results from this systematic review will provide important insight into the potential contextual factors which moderate or mediate the effectiveness, safety, and cost of virtual follow-up or care models for patients. SYSTEMATIC REVIEW REGISTRATION PROSPERO registration number CRD42020145210.
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Affiliation(s)
- Shannon E Kelly
- School of Epidemiology and Public Health, University of Ottawa, 101 - 600 Peter Morand Crescent, Ottawa, Ontario, K1G 5Z3, Canada.
| | - Tammy J Clifford
- School of Epidemiology and Public Health, University of Ottawa, 101 - 600 Peter Morand Crescent, Ottawa, Ontario, K1G 5Z3, Canada
| | - Doug Coyle
- School of Epidemiology and Public Health, University of Ottawa, 101 - 600 Peter Morand Crescent, Ottawa, Ontario, K1G 5Z3, Canada
| | - Janet Martin
- Department of Epidemiology and Biostatistics, Western University, London, Ontario, Canada
| | - Vivian Welch
- School of Epidemiology and Public Health, University of Ottawa, 101 - 600 Peter Morand Crescent, Ottawa, Ontario, K1G 5Z3, Canada
| | - Becky Skidmore
- Independent Information Specialist, Ottawa, Ontario, Canada
| | - David Birnie
- University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Ratika Parkash
- Division of Cardiology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Anthony S L Tang
- Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - George A Wells
- School of Epidemiology and Public Health, University of Ottawa, 101 - 600 Peter Morand Crescent, Ottawa, Ontario, K1G 5Z3, Canada
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Abstract
Several devices have been developed for heart failure (HF) treatment and monitoring. Among device-based monitoring tools, CardioMEMS™ has received growing research attention. This document reflects the key points of an ESC consensus meeting on implantable devices for monitoring in HF, with a particular focus on CardioMEMS™.
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Affiliation(s)
- Maurizio Volterrani
- Department of Medical Sciences, Centre for Clinical and Basic Research, IRCCS San Raffaele Pisana, via della Pisana, 235, 00163 Rome, Italy
| | - Ilaria Spoletini
- Department of Medical Sciences, Centre for Clinical and Basic Research, IRCCS San Raffaele Pisana, via della Pisana, 235, 00163 Rome, Italy
| | - Christiane Angermann
- Department of Medicine I, Cardiology and Comprehensive Heart Failure Center, University Hospital and University of Würzburg, Würzburg, Germany
| | - Giuseppe Rosano
- Department of Medical Sciences, Centre for Clinical and Basic Research, IRCCS San Raffaele Pisana, via della Pisana, 235, 00163 Rome, Italy
| | - Andrew Js Coats
- Department of Medical Sciences, Centre for Clinical and Basic Research, IRCCS San Raffaele Pisana, via della Pisana, 235, 00163 Rome, Italy
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21
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Sun J, Yang A, Zhao C, Liu F, Li Z. Recent progress of nanogenerators acting as biomedical sensors in vivo. Sci Bull (Beijing) 2019; 64:1336-47. [PMID: 36659663 DOI: 10.1016/j.scib.2019.07.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/31/2019] [Accepted: 06/17/2019] [Indexed: 01/21/2023]
Abstract
Since the nanogenerator (NG) was invented in 2006, it has been successfully developed and utilized to harvest various forms of mechanical energy in vivo. The NGs promote the progress of self-powered biomedical devices. Moreover, NGs can also be used as sensors to detect a variety of important physiological signals, which brings us closer to real-time, high-fidelity monitoring of physical and pathological information. This paper summarizes the in vivo applications of NGs as biomedical sensors, including in cardiac sensors, respiration sensors, blood pressure sensors, gastrointestinal sensors and bladder sensors. However, there are still many challenges in using NGs as sensors in vivo. For example, how can we minimize and encapsulate the NGs, how can we increase the stability and reliability during long-term detection, and how can we establish a corresponding relationship between the NG's electrical output and the physiological signals. It is also critical to follow the medical principles more closely in the development of self-powered sensors in the future. We believe that the self-powered sensors would promote the development of the next-generation healthcare monitoring systems.
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Bernardo R, Rodrigues A, Soares Dos Santos MP, Carneiro P, Lopes A, Sequeira Amaral J, Sequeira Amaral V, Morais R. Novel magnetic stimulation methodology for low-current implantable medical devices. Med Eng Phys 2019; 73:77-84. [PMID: 31477429 DOI: 10.1016/j.medengphy.2019.07.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 05/10/2019] [Accepted: 07/28/2019] [Indexed: 12/15/2022]
Abstract
Recent studies highlight the ability of inductive architectures to deliver therapeutic magnetic stimuli to target tissues and to be embedded into small-scale intracorporeal medical devices. However, to date, current micro-scale biomagnetic devices require very high electric current excitations (usually exceeding 1 A) to ensure the delivery of efficient magnetic flux densities. This is a critical problem as advanced implantable devices demand self-powering, stand-alone and long-term operation. This work provides, for the first time, a novel small-scale magnetic stimulation system that requires up to 50-fold lower electric current excitations than required by relevant biomagnetic technology recently proposed. Computational models were developed to analyse the magnetic stimuli distributions and densities delivered to cellular tissues during in vitro experiments, such that the feasibility of this novel stimulator can be firstly evaluated on cell culture tests. The results demonstrate that this new stimulative technology is able to deliver osteogenic stimuli (0.1-7 mT range) by current excitations in the 0.06-4.3 mA range. Moreover, it allows coil designs with heights lower than 1 mm without significant loss of magnetic stimuli capability. Finally, suitable core diameters and stimulator-stimulator distances allow to define heterogeneity or quasi-homogeneity stimuli distributions. These results support the design of high-sophisticated biomagnetic devices for a wide range of therapeutic applications.
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Affiliation(s)
- Rodrigo Bernardo
- Department of Mechanical Engineering, University of Aveiro, Aveiro, Portugal
| | - André Rodrigues
- Department of Mechanical Engineering, University of Aveiro, Aveiro, Portugal
| | - Marco P Soares Dos Santos
- Department of Mechanical Engineering, University of Aveiro, Aveiro, Portugal; Centre for Mechanical Technology and Automation (TEMA), University of Aveiro, Aveiro, Portugal; Associated Laboratory for Energy, Transports and Aeronautics (LAETA), Portugal.
| | - Pedro Carneiro
- Department of Mechanical Engineering, University of Aveiro, Aveiro, Portugal
| | - António Lopes
- Department of Physics, University of Aveiro, Aveiro, Portugal; Aveiro Institute of Materials, Aveiro, Portugal
| | - João Sequeira Amaral
- Department of Physics, University of Aveiro, Aveiro, Portugal; Aveiro Institute of Materials, Aveiro, Portugal
| | - Vítor Sequeira Amaral
- Department of Physics, University of Aveiro, Aveiro, Portugal; Aveiro Institute of Materials, Aveiro, Portugal
| | - Raul Morais
- University of Trás-os-Montes e Alto Douro, Vila Real, Portugal; Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Porto, Portugal
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Holschneider DP, Givrad TK, Yang J, Stewart SB, Francis SR, Wang Z, Maarek J. Cerebral perfusion mapping during retrieval of spatial memory in rats. Behav Brain Res 2019; 375:112116. [PMID: 31377254 DOI: 10.1016/j.bbr.2019.112116] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/26/2019] [Accepted: 07/26/2019] [Indexed: 12/24/2022]
Abstract
Studies of brain functional activation during spatial navigation using electrophysiology and immediate-early gene responses have typically targeted a limited number of brain regions. Our study provides the first whole brain analysis of cerebral activation during retrieval of spatial memory in the freely-moving rat. Rats (LEARNERS) were trained in the Barnes maze, an allocentric spatial navigation task, while CONTROLS received passive exposure. After 19 days, functional brain mapping was performed during recall by bolus intravenous injection of [14C]-iodoantipyrine using a novel subcutaneous minipump triggered by remote activation. Regional cerebral blood flow (rCBF)-related tissue radioactivity was analyzed by statistical parametric mapping from autoradiographic images of the three-dimensionally reconstructed brains. Functional connectivity was examined between regions of the spatial navigation circuit through interregional correlation analysis. Significant rCBF increases were noted in LEARNERS compared to CONTROLS broadly across the spatial navigation circuit, including the hippocampus (anterior dorsal CA1, posterior ventral CA1-3), subiculum, thalamus, striatum, medial septum, cerebral cortex, with decreases noted in the mammillary nucleus, amygdala and insula. LEARNERS showed a significantly greater positive correlation of rCBF of the ventral hippocampus with retrosplenial, lateral orbital, parietal and primary visual cortex, and a significantly more negative correlation with the mammillary nucleus, amygdala, posterior entorhinal cortex, and anterior thalamic nucleus. The complex sensory component of the spatial navigation task was underscored by broad activation across visual, somatosensory, olfactory, auditory and vestibular circuits which was enhanced in LEARNERS. Brain mapping facilitated by an implantable minipump represents a powerful tool for evaluation of mammalian behaviors dependent on locomotion.
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Affiliation(s)
- D P Holschneider
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States; Dept. of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States; Viterbi School of Engineering, Dept. of Biomedical Engineering, Los Angeles, CA, 90033, United States.
| | - T K Givrad
- Viterbi School of Engineering, Dept. of Biomedical Engineering, Los Angeles, CA, 90033, United States
| | - J Yang
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - S B Stewart
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - S R Francis
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - Z Wang
- Dept. of Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, United States
| | - Jmi Maarek
- Viterbi School of Engineering, Dept. of Biomedical Engineering, Los Angeles, CA, 90033, United States
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Pastori D, Miyazawa K, Li Y, Székely O, Shahid F, Farcomeni A, Lip GYH. Atrial high-rate episodes and risk of major adverse cardiovascular events in patients with cardiac implantable electronic devices. Clin Res Cardiol 2020; 109:96-102. [PMID: 31144064 DOI: 10.1007/s00392-019-01493-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 05/16/2019] [Indexed: 01/08/2023]
Abstract
BACKGROUND Patients with atrial high-rate episodes (AHREs) are at higher risk of thromboembolic events and mortality. The risk of major adverse cardiovascular events (MACE) in these patients is unknown. OBJECTIVE To investigate the risk of MACE in patients implanted with cardiac implantable electronic devices (CIEDs) developing AHREs METHODS AND RESULTS: We included 852 consecutive patients undergoing CIEDs implantation. Primary outcome was a composite endpoint of MACEs occurring after AHREs ≥ 5 min. AHRE was defined as > 175 bpm and lasting ≥ 5 min. We also performed a subgroup analysis in patients with the longest AHRE lasting ≥ 24 h. Cox regression analysis with time-dependent covariates was used to investigate the relationship between AHREs and MACEs. Mean age was 70.0 ± 13.6 years, and 39.3% were women: 325 patients developed AHREs ≥ 5 min [incidence rate (IR) 13.1% year 95% confidence interval (CI) 11.7-14.6] and 124 patients developed AHREs ≥ 24 h (IR 3.7%/year 95% CI 3.1-4.5). During a median follow-up of 37.0 months (IQR 19.0-64.3, 316,132 patient-years), 152 MACEs occurred (IR 4.85%/year, 95% CI 4.11-5.68). The IR of MACE occurring after AHREs onset was higher in patients developing AHREs ≥ 24 h (IR 1.13%/year) than AHREs ≥ 5 min (IR 0.63%/year, p = 0.030). Multivariable Cox regression analysis showed that AHREs ≥ 5 min (HR 1.788, 95% CI 1.247-2.562, p = 0.002), diabetes (HR 1.909, 95% CI 1.358-2.683, p < 0.001), heart failure (HR 2.203, 95% CI 1.527-3.178, p < 0.001), and coronary artery disease (HR 1.862, 95% CI 1.293-2.681, p = 0.001) were associated to MACE. This association was even stronger for AHREs ≥ 24 h (HR 2.390, 95% CI 1.481-3.857, p < 0.001). CONCLUSIONS Patients implanted with CIEDs developing AHREs show a significant risk for MACE, which is dependent on AHREs burden. Cardiovascular prevention strategies in this patient population are warranted.
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Kerneis M, Nafee T, Yee MK, Kazmi HA, Datta S, Zeitouni M, Afzal MK, Jafarizade M, Walia SS, Qamar I, Pitliya A, Kalayci A, Al Khalfan F, Gibson CM. Most Promising Therapies in Interventional Cardiology. Curr Cardiol Rep 2019; 21:26. [PMID: 30868280 DOI: 10.1007/s11886-019-1108-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
PURPOSE OF REVIEW The last 40 years of clinical research in interventional cardiology were extraordinarily innovative. This article will review the most promising up and coming interventional cardiovascular therapies, with a primary focus on the treatment of coronary artery disease. RECENT FINDINGS From the first stent, to the first transcatheter aortic valve implantation (TAVI), and the left appendage closure technique, percutaneous interventions revolutionized the treatment of multiple diseases and dramatically improved the prognosis of many patients. While these advances have decreased the risk of mortality in some patients (such as ST-elevation myocardial infarction), 15% of acute coronary syndrome (ACS) patients still experience recurrent ischemic events within the first year, challenging us to develop new pharmaceutical targets and new devices. The continued emergence of data supporting inflammation as a risk factor and pharmacologic target as well as data supporting the importance of cholesterol efflux have identified novel therapeutic targets that may play a major role in the improvement of prognosis of patients with coronary artery disease. In addition, novel medical devices are being developed to allow even earlier detection of acute cardiac events and to support high-risk percutaneous coronary interventions. Advances in computing and the ability to analyze large datasets will allow us to use artificial intelligence to augment the clinician patient experience, both in and out of the catheterization laboratory, with live procedural guidance as well as pre- and post-operative prognostication tools.
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Gilbert F, Cook M, O’Brien T, Illes J. Embodiment and Estrangement: Results from a First-in-Human "Intelligent BCI" Trial. Sci Eng Ethics 2019; 25:83-96. [PMID: 29129011 PMCID: PMC6418065 DOI: 10.1007/s11948-017-0001-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Accepted: 10/31/2017] [Indexed: 05/21/2023]
Abstract
While new generations of implantable brain computer interface (BCI) devices are being developed, evidence in the literature about their impact on the patient experience is lagging. In this article, we address this knowledge gap by analysing data from the first-in-human clinical trial to study patients with implanted BCI advisory devices. We explored perceptions of self-change across six patients who volunteered to be implanted with artificially intelligent BCI devices. We used qualitative methodological tools grounded in phenomenology to conduct in-depth, semi-structured interviews. Results show that, on the one hand, BCIs can positively increase a sense of the self and control; on the other hand, they can induce radical distress, feelings of loss of control, and a rupture of patient identity. We conclude by offering suggestions for the proactive creation of preparedness protocols specific to intelligent-predictive and advisory-BCI technologies essential to prevent potential iatrogenic harms.
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Affiliation(s)
- F. Gilbert
- Centre for Sensorimotor Neural Engineering, Department of Philosophy, University of Washington, Seattle, WA USA
- National Core for Neuroethics, Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, BC USA
- Australian Research Council DECRA Fellow, University of Tasmania, Hobart, Australia
| | - M. Cook
- Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
- Department of Neurology, St. Vincent’s Hospital, Melbourne, Australia
| | - T. O’Brien
- Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Parkville, Australia
| | - J. Illes
- National Core for Neuroethics, Division of Neurology, Department of Medicine, University of British Columbia, Vancouver, BC USA
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Angotzi GN, Boi F, Lecomte A, Miele E, Malerba M, Zucca S, Casile A, Berdondini L. SiNAPS: An implantable active pixel sensor CMOS-probe for simultaneous large-scale neural recordings. Biosens Bioelectron 2018; 126:355-364. [PMID: 30466053 DOI: 10.1016/j.bios.2018.10.032] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 09/25/2018] [Accepted: 10/09/2018] [Indexed: 11/18/2022]
Abstract
Large-scale neural recordings with high spatial and temporal accuracy are instrumental to understand how the brain works. To this end, it is of key importance to develop probes that can be conveniently scaled up to a high number of recording channels. Despite recent achievements in complementary metal-oxide semiconductor (CMOS) multi-electrode arrays probes, in current circuit architectures an increase in the number of simultaneously recording channels would significantly increase the total chip area. A promising approach for overcoming this scaling issue consists in the use of the modular Active Pixel Sensor (APS) concept, in which a small front-end circuit is located beneath each electrode. However, this approach imposes challenging constraints on the area of the in-pixel circuit, power consumption and noise. Here, we present an APS CMOS-probe technology for Simultaneous Neural recording that successfully addresses all these issues for whole-array read-outs at 25 kHz/channel from up to 1024 electrode-pixels. To assess the circuit performances, we realized in a 0.18 μm CMOS technology an implantable single-shaft probe with a regular array of 512 electrode-pixels with a pitch of 28 μm. Extensive bench tests showed an in-pixel gain of 45.4 ± 0.4 dB (low pass, F-3 dB = 4 kHz), an input referred noise of 7.5 ± 0.67 μVRMS (300 Hz to 7.5 kHz) and a power consumption <6 μW/pixel. In vivo acute recordings demonstrate that our SiNAPS CMOS-probe can sample full-band bioelectrical signals from each electrode, with the ability to resolve and discriminate activity from several packed neurons both at the spatial and temporal scale. These results pave the way to new generations of compact and scalable active single/multi-shaft brain recording systems.
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Affiliation(s)
| | - Fabio Boi
- Fondazione Istituto Italiano di Tecnologia (IIT), NetS3 Lab, Genova, Italy
| | - Aziliz Lecomte
- Fondazione Istituto Italiano di Tecnologia (IIT), NetS3 Lab, Genova, Italy
| | - Ermanno Miele
- Fondazione Istituto Italiano di Tecnologia (IIT), NetS3 Lab, Genova, Italy
| | - Mario Malerba
- Fondazione Istituto Italiano di Tecnologia (IIT), NetS3 Lab, Genova, Italy
| | - Stefano Zucca
- Fondazione Istituto Italiano di Tecnologia (IIT), Optical Approaches to Brain Function, Lab, Genova, Italy
| | - Antonino Casile
- Fondazione Istituto Italiano di Tecnologia (IIT), CTNSC-UniFe, Ferrara, Italy
| | - Luca Berdondini
- Fondazione Istituto Italiano di Tecnologia (IIT), NetS3 Lab, Genova, Italy
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Chen SY, Ceresnak SR, Motonaga KS, Trela A, Hanisch D, Dubin AM. Antibiotic Prophylaxis Practices in Pediatric Cardiac Implantable Electronic Device Procedures: A Survey of the Pediatric And Congenital Electrophysiology Society (PACES). Pediatr Cardiol 2018; 39:1129-1133. [PMID: 29564522 DOI: 10.1007/s00246-018-1865-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/13/2018] [Indexed: 11/30/2022]
Abstract
Cardiac implantable electronic device (CIED) infections are associated with significant morbidity in the pediatric device population, with a tenfold higher risk of infection in children compared to adults. The 2010 American Heart Association (AHA) guidelines recommend a single dose of systemic antibiotic (ABX) prophylaxis prior to CIED implantation and no post-operative (OP) ABX. However, there is limited data regarding adherence to this recommendation among the pediatric community. To assess current clinical practices for CIED ABX prophylaxis in pediatrics; whether the AHA guidelines are being followed; and if not, the reasons for non-adherence. An anonymous web-based survey was sent to physician members of the Pediatric And Congenital Electrophysiology Society regarding ABX prophylaxis for new CIED implants and reoperations. 75 (25%) members responded. Only 7% of respondents follow the 2010 AHA guidelines. While all respondents give pre-OP IV ABX, 64% routinely treat patients with 24-h post-OP IV ABX with additional oral or IV therapy. 69% of respondents are cognizant of the guidelines but 88% of those cognizant do not follow the guidelines for a variety of reasons including lack of data and different substrate (pediatric patients). 79% stated that pediatric-specific data would be required for them to change their practice and follow the published guidelines. The majority of pediatric EP physicians who responded to this survey do not follow the current AHA guidelines on ABX prophylaxis and administer post-OP ABX. Most pediatric EP physicians believe that the increased risk of infection in children merits additional ABX.
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Affiliation(s)
- Spenser Y Chen
- Pediatric Cardiology, Stanford University School of Medicine, 750 Welch Rd. Suite 321, Palo Alto, CA, 94304, USA
| | - Scott R Ceresnak
- Pediatric Cardiology, Stanford University School of Medicine, 750 Welch Rd. Suite 321, Palo Alto, CA, 94304, USA
| | - Kara S Motonaga
- Pediatric Cardiology, Stanford University School of Medicine, 750 Welch Rd. Suite 321, Palo Alto, CA, 94304, USA
| | - Anthony Trela
- Pediatric Cardiology, Stanford University School of Medicine, 750 Welch Rd. Suite 321, Palo Alto, CA, 94304, USA
| | - Debra Hanisch
- Pediatric Cardiology, Stanford University School of Medicine, 750 Welch Rd. Suite 321, Palo Alto, CA, 94304, USA
| | - Anne M Dubin
- Pediatric Cardiology, Stanford University School of Medicine, 750 Welch Rd. Suite 321, Palo Alto, CA, 94304, USA.
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Pastori D, Miyazawa K, Li Y, Shahid F, Hado H, Lip GYH. Inflammation and the risk of atrial high-rate episodes (AHREs) in patients with cardiac implantable electronic devices. Clin Res Cardiol 2018; 107:772-7. [PMID: 29667016 DOI: 10.1007/s00392-018-1244-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 04/09/2018] [Indexed: 12/03/2022]
Abstract
Introduction Atrial high-rate episodes (AHREs) are associated with an increased risk of developing atrial fibrillation and thromboembolism. The characteristics of ‘real world’ patients developing AHREs are poorly known. Methods We included 496 consecutive patients with cardiac implantable electronic devices (CIEDs). Primary endpoint was occurrence of AHREs, defined as > 175 bpm and lasting > 5 min, in a median follow-up of 16.5 (IQR 3.9–38.6) months (1082.4 patient-years). We also tested the predictive value of clinical risk scores for AHREs. Results Mean age was 68.8 ± 14.0 years, and 35.5% were women; AHREs were recorded in 173 patients [34.7%, 16.0%/year, 95% confidence interval (CI) 13.7–18.6]. Multivariable Cox regression analysis showed that age [hazard ratio (HR) 1.020, 95% CI 1.004–1.035, p = 0.011], prior AF (HR 3.521, 95% CI 2.831–5.206, p < 0.001), white cell count (HR 1.039, 95% CI 1.007–1.072, p = 0.016) and high C reactive protein (CRP; HR 1.039, 95% CI 1.021–2.056, p = 0.038) were independently associated with AHREs. ROC curve analysis showed that the APPLE score (C statistic 0.53, 95% CI 0.48–0.59; p = 0.296) ALARMEc score (C statistic 0.51, 95% CI 0.44–0.57; p = 0.810) were non-significantly associated with AHRE. Similar results were obtained for CHADS2 and CHA2DS2VASc score Conclusion AHREs are common in CIEDs patients, with age, prior AF, inflammatory markers (high CRP, white cell count) being factors associated with AHREs onset. Clinical risk scores showed limited value for AHREs prediction in this cohort. Electronic supplementary material The online version of this article (10.1007/s00392-018-1244-0) contains supplementary material, which is available to authorized users.
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Inoue T, Fujii M, Kida H, Yamakawa T, Maruta Y, Tokiwa T, He Y, Nomura S, Owada Y, Yamakawa T, Suzuki M. Epidural focal brain cooling abolishes neocortical seizures in cats and non-human primates. Neurosci Res 2017; 122:35-44. [PMID: 28450153 DOI: 10.1016/j.neures.2017.04.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 02/07/2017] [Accepted: 04/07/2017] [Indexed: 11/24/2022]
Abstract
Focal brain cooling (FBC) is under investigation in preclinical trials of intractable epilepsy (IE), including status epilepticus (SE). This method has been studied in rodents as a possible treatment for epileptic disorders, but more evidence from large animal studies is required. To provide evidence that FBC is a safe and effective therapy for IE, we investigated if FBC using a titanium cooling plate can reduce or terminate focal neocortical seizures without having a significant impact on brain tissue. Two cats and two macaque monkeys were chronically implanted with an epidural FBC device over the somatosensory and motor cortex. Penicillin G was delivered via the intracranial cannula for induction of local seizures. Repetitive FBC was performed using a cooling device implanted for a medium-term period (FBC for 30min at least twice every week; 3 months total) in three of the four animals. The animals exhibited seizures with repetitive epileptiform discharges (EDs) after administration of penicillin G, and these discharges decreased at less than 20°C cooling with no adverse histological effects. The results of this study suggest that epidural FBC is a safe and effective potential treatment for IE and SE.
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Affiliation(s)
- Takao Inoue
- Department of Neurosurgery, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan.
| | - Masami Fujii
- Department of Neurosurgery, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Hiroyuki Kida
- Department of Physiology, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Toshitaka Yamakawa
- Department of Electrical and Electronics Engineering, Shizuoka University, Hamamatsu, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Yuichi Maruta
- Department of Neurosurgery, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Tatsuji Tokiwa
- Department of Brain Science and Engineering, Kyushu Institute of Technology, Kyushu, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Yeting He
- Department of Neurosurgery, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Sadahiro Nomura
- Department of Neurosurgery, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Yuji Owada
- Department of Organ Anatomy, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Takeshi Yamakawa
- Department of Brain Science and Engineering, Kyushu Institute of Technology, Kyushu, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
| | - Michiyasu Suzuki
- Department of Neurosurgery, Yamaguchi University School of Medicine, Ube, Japan; Consortium of ADvanced Epilepsy Treatment (CADET), Japan
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Harilall SL, Choonara YE, Tomar LK, Tyagi C, Kumar P, du Toit LC, Modi G, Naidoo D, Iyuke SE, Danckwerts MP, Pillay V. Development and in vivo evaluation of an implantable nano-enabled multipolymeric scaffold for the management of AIDS dementia complex (ADC). Int J Pharm 2015; 496:863-77. [PMID: 26456249 DOI: 10.1016/j.ijpharm.2015.10.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 10/04/2015] [Indexed: 10/22/2022]
Abstract
This study reports the use of biocompatible and biodegradable polymers for the formulation and design of an implantable multipolymeric drug delivery device (MDDD) for the management of AIDS dementia complex (ADC), a debilitating condition affecting the cognitive, motor and behavioral systems in HIV+ individuals. A 3-factor Box-Behnken statistical design was employed for the optimization of nanoparticle and multipolymeric scaffold formulations. Fifteen formulations were generated using the Box-Behnken template, which were assessed for physicochemical and physicomechanical characterization. The optimised nanoparticle formulation yielded nanoparticles measuring 68.04nm in size and zeta potential (ZP) of -13.4mV was calculated for the colloidal system. In an attempt to further retard drug release and to formulate a device for implantation in the frontal lobe of the brain, nanoparticles were dispersed within a multipolymeric matrix. Matrix erosion was calculated at 28% for multipolymeric scaffold and a matrix resilience of 4.451% was observed 30 days post exposure to PBS, indicating slow degradation of the MDDD. In vivo studies showed 12.793ng/mL and 35.225ng/mL AZT level in plasma and CSF. In view of the physicomechanical properties, in vitro and in vivo drug release kinetics of MDDD makes it a potential candidate for the management of the ADC.
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Affiliation(s)
- Sheri-Lee Harilall
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Yahya E Choonara
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Lomas Kumar Tomar
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Charu Tyagi
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Pradeep Kumar
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Lisa C du Toit
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Girish Modi
- Department of Neurology, Division of Neurosciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Dinesh Naidoo
- Department of Neurosurgery, Division of Neurosciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Sunny E Iyuke
- School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Johannesburg, South Africa
| | - Michael P Danckwerts
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa
| | - Viness Pillay
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, 7 York Road, Parktown, 2193, South Africa.
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Abstract
BACKGROUND Stroke without an identifiable cause is frightening to patients and their families and is frustrating for the caring physician. Approximately 30% of patients with cardiac implanted electronic devices have some evidence of atrial fibrillation (AF), and much of it is silent: asymptomatic, and previously unrecognized. OBJECTIVE The purpose of this review is to examine "silent AF" as a potential cause of cryptogenic stroke. METHODS/RESULTS We begin by reviewing most of the published literature on screening for AF with different monitoring technologies in the setting of cryptogenic stroke. We present the results of 2 recent large randomized trials, CRYSTAL AF and EMBRACE, which compare standard of care monitoring in cryptogenic stroke patients to invasive and noninvasive monitoring strategies, respectively. Finally, we review the relationship of silent AF to stroke in the cardiac implanted electronic device population. Patient selection, duration of monitoring, sensitivity and specificity of monitoring technology, patient compliance, and several other factors affect the yield of AF detection during monitoring. CONCLUSION Data suggest that silent AF is identified in approximately 30% of cryptogenic stroke patients and has important therapeutic implications. Oral anticoagulation likely should be prescribed when silent AF is detected.
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Affiliation(s)
- Taya V Glotzer
- Hackensack University Medical Center, Hackensack, New Jersey,.
| | - Paul D Ziegler
- Cardiac Rhythm Disease Management Division, Medtronic Inc, Mounds View, Minnesota
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Abstract
OBJECTIVES The goal of this paper is to review some important issues occurring during the past year in Implantable devices. METHODS First cardiac implantable device was proposed to maintain an adequate heart rate, either because the heart's natural pacemaker is not fast enough, or there is a block in the heart's electrical conduction system. During the last forty years, pacemakers have evolved considerably and become programmable and allow to configure specific patient optimum pacing modes. Various technological aspects (electrodes, connectors, algorithms diagnosis, therapies, ...) have been progressed and cardiac implants address several clinical applications: management of arrhythmias, cardioversion / defibrillation and cardiac resynchronization therapy. RESULTS Observed progress was the miniaturization of device, increased longevity, coupled with efficient pacing functions, multisite pacing modes, leadless pacing and also a better recognition of supraventricular or ventricular tachycardia's in order to deliver appropriate therapy. Subcutaneous implant, new modes of stimulation (leadless implant or ultrasound lead), quadripolar lead and new sensor or new algorithm for the hemodynamic management are introduced and briefly described. Each times, the main result occurring during the two past years are underlined and repositioned from the history, remaining limitations are also addressed. CONCLUSION Some important technological improvements were described. Nevertheless, news trends for the future are also considered in a specific session such as the remote follow-up of the patient or the treatment of heart failure by neuromodulation.
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Affiliation(s)
- G Carrault
- Guy Carrault, Laboratoire de Traitement du Signal et de l'Image, (LTSI) - INSERM UMR 1099, Campus de Beaulieu, Bâtiment 22, F-35042 RENNES CEDEX, France, E-mail: , http://www.ltsi.univ-rennes1.fr
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34
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Abstract
The precise role atrial fibrillation (AF) plays in increasing the risk of stroke is less well understood; this is especially true for the implanted device population. Current cardiac implanted electronic devices have a very high sensitivity and specificity for true AF detection. It does not seem to matter if the AF episode is proximal to the stroke event, and risk seems to be increased by relatively brief AF episodes. The appearance of new atrial high-rate episodes increases thromboembolic event rates. Until larger trials or registries are conducted, it is important to follow established guidelines regarding anticoagulation.
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Affiliation(s)
- Taya V Glotzer
- Hackensack University Medical Center, Hackensack, NJ 07601, USA.
| | - Paul D Ziegler
- Medtronic Cardiac Rhythm Disease Management Division, Medtronic Inc, 8200 Coral Sea St. NE, Mounds View, MN 55112, USA
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Kim SH, Ishiyama K, Hashi S, Shiraishi Y, Hayatsu Y, Akiyama M, Saiki Y, Yambe T. Preliminary validation of a new magnetic wireless blood pump. Artif Organs 2013; 37:920-6. [PMID: 23634711 DOI: 10.1111/aor.12093] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In general, a blood pump must be small, have a simple configuration, and have sufficient hydrodynamic performance. Herein, we introduce new mechanisms for a wireless blood pump that is small and simple and provides wireless and battery-free operation. To achieve wireless and battery-free operation, we implement magnetic torque and force control methods that use two external drivers: an external coil and a permanent magnet with a DC-motor, respectively. Power harvesting can be used to drive an electronic circuit for wireless monitoring (the observation of the pump conditions and temperature) without the use of an internal battery. The power harvesting will be used as a power source to drive other electronic devices, such as various biosensors with their driving circuits. To have both a compact size and sufficient pumping capability, the fully magnetic impeller has five stages and each stage includes four backward-curved blades. The pump has total and inner volumes of 20 and 9.8 cc, respectively, and weighs 52 g. The pump produces a flow rate of approximately 8 L/min at 80 mm Hg and the power generator produces 0.3 W of electrical power at 120 Ω. The pump also produces a minimum flow rate of 1.5 L/min and a pressure of 30 mm Hg for circulation at a maximum distance of 7.5 cm.
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Affiliation(s)
- Sung Hoon Kim
- Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
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