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Hampson R, Senior R, Ring L, Robinson S, Augustine DX, Becher H, Anderson N, Willis J, Chandrasekaran B, Kardos A, Siva A, Leeson P, Rana BS, Chahal N, Oxborough D. Contrast echocardiography: a practical guideline from the British Society of Echocardiography. Echo Res Pract 2023; 10:23. [PMID: 37964335 PMCID: PMC10648732 DOI: 10.1186/s44156-023-00034-9] [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: 07/26/2023] [Accepted: 10/11/2023] [Indexed: 11/16/2023] Open
Abstract
Ultrasound contrast agents (UCAs) have a well-established role in clinical cardiology. Contrast echocardiography has evolved into a routine technique through the establishment of contrast protocols, an excellent safety profile, and clinical guidelines which highlight the incremental prognostic utility of contrast enhanced echocardiography. This document aims to provide practical guidance on the safe and effective use of contrast; reviews the role of individual staff groups; and training requirements to facilitate its routine use in the echocardiography laboratory.
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Affiliation(s)
| | - Roxy Senior
- London North West University Healthcare NHS Trust, London, UK.
- Royal Brompton Hospital and Imperial College, London, UK.
| | - Liam Ring
- West Suffolk Hospital NHS Foundation Trust, Bury St Edmunds, UK
| | | | - Daniel X Augustine
- Royal United Hospitals Bath NHS Foundation Trust, Bath, UK
- Department for, Health University of Bath, Bath, UK
| | - Harald Becher
- Alberta Heart Institute, University of Alberta Hospital, Edmonton, Canada
| | - Natasha Anderson
- Warrington and Halton Teaching Hospital NHS Foundation Trust, Warrington, UK
| | - James Willis
- Royal United Hospitals Bath NHS Foundation Trust, Bath, UK
| | | | - Attila Kardos
- Translational Cardiovascular Research Group, Department of Cardiology, Milton Keynes University Hospital, Milton Keynes, UK
- Faculty of Medicine and Health Sciences, University of Buckingham, Buckingham, UK
| | | | - Paul Leeson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Navtej Chahal
- London North West University Healthcare NHS Trust, London, UK
| | - David Oxborough
- Liverpool Centre for Cardiovascular Science, Liverpool John Moores University, Liverpool, UK
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Rutherford A, Chandrasekaran B, Petrou M, Ramcharitar S. Giant proximal left anterior descending aneurysm causing multi-vessel myocardial ischaemia: the pressure is on-a case report. Eur Heart J Case Rep 2023; 7:ytad550. [PMID: 38025138 PMCID: PMC10665038 DOI: 10.1093/ehjcr/ytad550] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 09/20/2023] [Accepted: 11/06/2023] [Indexed: 12/01/2023]
Abstract
Background Giant coronary artery aneurysms are a rare cause of myocardial ischaemia. Due to the rarity and variety of presentation of these cases, no standardized investigation or treatment has been established for management. We report a case study of a giant proximal left anterior descending (LAD) coronary aneurysm causing myocardial ischaemia due to the pressure effect from the weight of the aneurysm as well as from a change in rheology from a 'steal effect' on both the LAD and left circumflex (LCx) arteries. Case summary A 55-year-old patient presents initially with a history of angina. Initial investigation with computed tomography (CT) was suboptimal, requiring invasive diagnostic angiography, which detects a giant proximal LAD aneurysm. Subsequent investigations, with CT-fractional flow reserve (FFR) and stress echocardiography (ECHO), correlated to identify multi-vessel ischaemia resulting from the aneurysm. The patient was managed with multi-disciplinary team-led surgical resection and triple coronary artery bypass grafts with good results. Discussion This case highlights the complexity of coronary anomalies and importance of additional functional three-dimensional imaging on top of the static computational tomography coronary angiography analysis. Together, these two complimentary investigations qualitatively enabled the assessment of anomaly with surrounding structures such that the possibility of a mass effect on the LCx artery results in a positive stress test. Furthermore, this is a novel use of CT-FFR for coronary anomalies and it demonstrated good correlation of LAD territory ischaemia between CT-FFR and the stress ECHO.
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Affiliation(s)
| | | | - Mario Petrou
- Royal Brompton and Harefield Hospitals, Sydney Street, London SW3 6NP, UK
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Hewitson LJ, Cadiz S, Al-Sayed S, Fellows S, Amin A, Asimakopoulos G, Barnes E, Beale A, Browne S, Chandrasekaran B, Dalby M, Foley P, Hawkins M, Haynes D, Heng EL, Hyde T, Kabir T, Khavandi A, Mirsadraee S, McCrea W, Petrou M, Senior R, Smith D, Smith R, Spartera M, Wamil M, Panoulas V, Rahbi H. Time to TAVI: streamlining the pathway to treatment. Open Heart 2023; 10:e002170. [PMID: 37666643 PMCID: PMC10481834 DOI: 10.1136/openhrt-2022-002170] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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] [Received: 11/08/2022] [Accepted: 07/27/2023] [Indexed: 09/06/2023] Open
Abstract
INTRODUCTION Severe aortic stenosis is a major cause of morbidity and mortality. The existing treatment pathway for transcatheter aortic valve implantation (TAVI) traditionally relies on tertiary Heart Valve Centre workup. However, this has been associated with delays to treatment, in breach of British Cardiovascular Intervention Society targets. A novel pathway with emphasis on comprehensive patient workup at a local centre, alongside close collaboration with a Heart Valve Centre, may help reduce the time to TAVI. METHODS The centre performing local workup implemented a novel TAVI referral pathway. Data were collected retrospectively for all outpatients referred for consideration of TAVI to a Heart Valve Centre from November 2020 to November 2021. The main outcome of time to TAVI was calculated as the time from Heart Valve Centre referral to TAVI, or alternative intervention, expressed in days. For the centre performing local workup, referral was defined as the date of multidisciplinary team discussion. For this centre, a total pathway time from echocardiographic diagnosis to TAVI was also evaluated. A secondary outcome of the proportion of referrals proceeding to TAVI at the Heart Valve Centre was analysed. RESULTS Mean±SD time from referral to TAVI was significantly lower at the centre performing local workup, when compared with centres with traditional referral pathways (32.4±64 to 126±257 days, p<0.00001). The total pathway time from echocardiographic diagnosis to TAVI for the centre performing local workup was 89.9±67.6 days, which was also significantly shorter than referral to TAVI time from all other centres (p<0.003). Centres without local workup had a significantly lower percentage of patients accepted for TAVI (49.5% vs 97.8%, p<0.00001). DISCUSSION A novel TAVI pathway with emphasis on local workup within a non-surgical centre significantly reduced both the time to TAVI and rejection rates from a Heart Valve Centre. If adopted across the other centres, this approach may help improve access to TAVI.
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Affiliation(s)
| | - Suzane Cadiz
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | | | - Sarah Fellows
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Alaaeldin Amin
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | | | - Edward Barnes
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Andrew Beale
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Suzy Browne
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | | | - Miles Dalby
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | - Paul Foley
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Mark Hawkins
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Douglas Haynes
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Ee Ling Heng
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | - Tom Hyde
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Tito Kabir
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | - Ali Khavandi
- Royal United Hospitals Bath NHS Foundation Trust, Bath, UK
| | | | - William McCrea
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
| | - Mario Petrou
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | - Roxy Senior
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | - David Smith
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | - Robert Smith
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
| | - Marco Spartera
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
- Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | | | - Vasileios Panoulas
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
- Cardiovascular Sciences, Imperial College London National Heart and Lung Institute, London, UK
| | - Hazim Rahbi
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
- Royal Brompton & Harefield NHS Foundation Trust, London, UK
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Das A, Azarudheen S, Chandrasekaran B, Fernandes S, Davis F. The plausible effects of wearing face masks on sports performance - A scoping review. Sci Sports 2023; 38:S0765-1597(23)00133-8. [PMID: 38620146 PMCID: PMC10300654 DOI: 10.1016/j.scispo.2022.12.006] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 12/29/2022] [Indexed: 04/17/2024]
Abstract
Objectives The objectives of this scoping review are to discuss, firstly, the positive aspects of wearing face masks during training (such as a barrier to COVID-19 transmission, air pollutant exposure, and adding load on respiratory resistance flow); secondly, the negative aspects (adverse effects on body temperature and hypoxia risks); and thirdly, the training responses of wearing face masks on aerobic and anaerobic performance. News Besides social distancing and hand hygiene, wearing a face mask is proposed to be the prime advocacy for virus containment. During the period of high risk of contamination, the return to sport guidelines proposed by international and national sport federations included wearing face masks during training sessions. However, it is necessary to discuss the pros and cons of wearing face masks during exercise. Prospects Although it was essential to wear a face mask during exercise or sport-specific training, there is conflicting evidence on the implications of the use of face masks on physical, physiological as well as psychological well-being or performance. Based on the conflicting empirical findings and anecdotal evidence, certain recommendations have been made for adequate use of face masks during exercise; both to break the chain of transmission and prevent the physiological compromise expected from wearing face masks during exercise. The present review can help stakeholders balance sport guidelines in the event of a respiratory virus pandemic with athlete safety. Conclusion Conflicting evidence of mechanistic links between the dose of exercise and the possible adverse effects associated with exercising with face masks is available. Adequately powered studies with strong methodological quality on appropriate selection of masks and usage based on the intensity, duration, and type of sport, age, and gender is needed now for the stakeholders to make informed decisions with respect to exercising with face masks.
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Affiliation(s)
- A Das
- Department of Sports Science and Yoga, Ramakrishna Mission Vivekananda Educational and Research Institute, Belur Math, Howrah, West Bengal, India
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, India
| | - S Azarudheen
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, India
- Center for Sports Science, Medicine and Research, Manipal Academy of Higher Education, Manipal, India
| | - B Chandrasekaran
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, India
- Center for Sports Science, Medicine and Research, Manipal Academy of Higher Education, Manipal, India
| | - S Fernandes
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, India
- Center for Sports Science, Medicine and Research, Manipal Academy of Higher Education, Manipal, India
| | - F Davis
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, India
- Center for Sports Science, Medicine and Research, Manipal Academy of Higher Education, Manipal, India
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O’Driscoll JM, Hawkes W, Beqiri A, Mumith A, Parker A, Upton R, McCourt A, Woodward W, Dockerill C, Sabharwal N, Kardos A, Augustine DX, Balkhausen K, Chandrasekaran B, Firoozan S, Marciniak A, Heitner S, Yadava M, Kaul S, Sarwar R, Sharma R, Woodward G, Leeson P. Left ventricular assessment with artificial intelligence increases the diagnostic accuracy of stress echocardiography. Eur Heart J Open 2022; 2:oeac059. [PMID: 36284642 PMCID: PMC9580364 DOI: 10.1093/ehjopen/oeac059] [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] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/26/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
AIMS To evaluate whether left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS), automatically calculated by artificial intelligence (AI), increases the diagnostic performance of stress echocardiography (SE) for coronary artery disease (CAD) detection. METHODS AND RESULTS SEs from 512 participants who underwent a clinically indicated SE (with or without contrast) for the evaluation of CAD from seven hospitals in the UK and US were studied. Visual wall motion scoring (WMS) was performed to identify inducible ischaemia. In addition, SE images at rest and stress underwent AI contouring for automated calculation of AI-LVEF and AI-GLS (apical two and four chamber images only) with Ultromics EchoGo Core 1.0. Receiver operator characteristic curves and multivariable risk models were used to assess accuracy for identification of participants subsequently found to have CAD on angiography. Participants with significant CAD were more likely to have abnormal WMS, AI-LVEF, and AI-GLS values at rest and stress (all P < 0.001). The areas under the receiver operating characteristics for WMS index, AI-LVEF, and AI-GLS at peak stress were 0.92, 0.86, and 0.82, respectively, with cut-offs of 1.12, 64%, and -17.2%, respectively. Multivariable analysis demonstrated that addition of peak AI-LVEF or peak AI-GLS to WMS significantly improved model discrimination of CAD [C-statistic (bootstrapping 2.5th, 97.5th percentile)] from 0.78 (0.69-0.87) to 0.83 (0.74-0.91) or 0.84 (0.75-0.92), respectively. CONCLUSION AI calculation of LVEF and GLS by contouring of contrast-enhanced and unenhanced SEs at rest and stress is feasible and independently improves the identification of obstructive CAD beyond conventional WMSI.
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Affiliation(s)
| | | | - Arian Beqiri
- Ultromics Ltd, 4630 Kingsgate, Cascade Way, Oxford Business Park South, Oxford OX4 2SU, UK
| | - Angela Mumith
- Ultromics Ltd, 4630 Kingsgate, Cascade Way, Oxford Business Park South, Oxford OX4 2SU, UK
| | - Andrew Parker
- Ultromics Ltd, 4630 Kingsgate, Cascade Way, Oxford Business Park South, Oxford OX4 2SU, UK
| | - Ross Upton
- Ultromics Ltd, 4630 Kingsgate, Cascade Way, Oxford Business Park South, Oxford OX4 2SU, UK
- Cardiovascular Clinical Research Facility, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Annabelle McCourt
- Cardiovascular Clinical Research Facility, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - William Woodward
- Cardiovascular Clinical Research Facility, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Cameron Dockerill
- Cardiovascular Clinical Research Facility, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Nikant Sabharwal
- Oxford Heart Centre, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK
| | - Attila Kardos
- Department of Cardiology, Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes MK6 5LD, UK
| | - Daniel X Augustine
- Department of Cardiology, Royal United Hospitals NHS Foundation Trust, Bath BA1 3NG, UK
- Department for Health, University of Bath, Bath BA2 7JU, UK
| | - Katrin Balkhausen
- Department of Cardiology, Royal Berkshire NHS Foundation Trust, Reading RG1 5AN, UK
| | | | - Soroosh Firoozan
- Department of Cardiology, Buckinghamshire Healthcare NHS Trust, High Wycombe HP7 0JD, UK
| | - Anna Marciniak
- Department of Cardiology, St George’s University Hospitals NHS Foundation Trust, Blackshaw Road, Tooting, London SW17 0QT, UK
| | - Stephen Heitner
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Mrinal Yadava
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Sanjiv Kaul
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Rizwan Sarwar
- Ultromics Ltd, 4630 Kingsgate, Cascade Way, Oxford Business Park South, Oxford OX4 2SU, UK
- Cardiovascular Clinical Research Facility, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Oxford Heart Centre, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK
- Experimental Therapeutics, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Rajan Sharma
- Department of Cardiology, St George’s University Hospitals NHS Foundation Trust, Blackshaw Road, Tooting, London SW17 0QT, UK
| | - Gary Woodward
- Ultromics Ltd, 4630 Kingsgate, Cascade Way, Oxford Business Park South, Oxford OX4 2SU, UK
| | - Paul Leeson
- Corresponding author. Tel: +44 (0)1865 572846, Fax: +44 (0)1865 740449,
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Chandra Mohan N, Foley P, Chandrasekaran B. A case report of successful physiological pacing in a patient with lamin A/C cardiomyopathy. Eur Heart J Case Rep 2022; 6:ytac324. [PMID: 36045645 PMCID: PMC9426304 DOI: 10.1093/ehjcr/ytac324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/08/2022] [Accepted: 07/29/2022] [Indexed: 11/29/2022]
Abstract
Background Lamin A/C (LMNA) mutations account for 5–8% of familial dilated cardiomyopathies, and can manifest with conduction abnormalities and ventricular arrhythmias in 78% of patients. Therefore, when suspected, it is important to implant the correct type of device. Case summary A 52-year-old gentleman with a family history of cardiomyopathy, presented with asymptomatic atrial fibrillation and complete atrioventricular block associated with a narrow QRS interval. Investigations confirmed dilated and severely impaired left ventricular systolic function. He underwent successful conduction system pacing in combination with a primary prevention defibrillator. Genetic screening confirmed LMNA cardiomyopathy. During 3 years follow up, his left ventricular function remained unchanged with stable conduction system capture and he received appropriate therapy from his device for ventricular tachycardia. Discussion His-bundle pacing promotes rapid and synchronous activation of the ventricles via the intrinsic conduction system of the heart. In selected individuals with LMNA cardiomyopathy, conduction system pacing is viable alternative to conventional cardiac resynchronization therapy using coronary sinus tributaries.
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Affiliation(s)
- Nitin Chandra Mohan
- Cardiology, The Great Western Hospitals NHS Trust , Marlborough Road, Swindon SN3 6BB , UK
| | - Paul Foley
- Cardiology, The Great Western Hospitals NHS Trust , Marlborough Road, Swindon SN3 6BB , UK
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Cowie MR, Flett A, Cowburn P, Foley P, Chandrasekaran B, Loke I, Critoph C, Gardner RS, Guha K, Betts TR, Carr-White G, Zaidi A, Lim HS, Hayward C, Patwala A, Rogers D, Pettit S, Gazzola C, Henderson J, Adamson PB. Real-world evidence in a national health service: results of the UK CardioMEMS HF System Post-Market Study. ESC Heart Fail 2021; 9:48-56. [PMID: 34882989 PMCID: PMC8787982 DOI: 10.1002/ehf2.13748] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [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: 07/15/2021] [Revised: 11/02/2021] [Accepted: 11/18/2021] [Indexed: 11/10/2022] Open
Abstract
Aims The CardioMEMS HF System Post‐Market Study (COAST) was designed to evaluate the safety, effectiveness, and feasibility of haemodynamic‐guided heart failure (HF) management using a small sensor implanted in the pulmonary artery of New York Heart Association (NYHA) Class III HF patients in the UK, Europe, and Australia. Methods and results COAST is a prospective, international, multicentre, open‐label clinical study (NCT02954341). The primary clinical endpoint compares annualized HF hospitalization rates after 1 year of haemodynamic‐guided management vs. the year prior to sensor implantation in patients with NYHA Class III symptoms and a previous HF hospitalization. The primary safety endpoints assess freedom from device/system‐related complications and pressure sensor failure after 2 years. Results from the first 100 patients implanted at 14 out of the 15 participating centres in the UK are reported here. At baseline, all patients were in NYHA Class III, 70% were male, mean age was 69 ± 12 years, and 39% had an aetiology of ischaemic cardiomyopathy. The annualized HF hospitalization rate after 12 months was 82% lower [95% confidence interval 72–88%] than the previous 12 months (0.27 vs. 1.52 events/patient‐year, respectively, P < 0.0001). Freedom from device/system‐related complications and pressure sensor failure at 2 years was 100% and 99%, respectively. Conclusions Remote haemodynamic‐guided HF management, using frequent assessment of pulmonary artery pressures, was successfully implemented at 14 specialist centres in the UK. Haemodynamic‐guided HF management was safe and significantly reduced hospitalization in a group of high‐risk patients. These results support implementation of this innovative remote management strategy to improve outcome for patients with symptomatic HF. Clinical registration number: ClinicalTrials.gov identifier: NCT02954341.
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Affiliation(s)
- Martin R Cowie
- Royal Brompton Hospital (Guy's and St Thomas' NHS Foundation Trust), Sydney Street, London, SW3 6NP, UK
| | - Andrew Flett
- University Hospital Southampton, Southampton, UK
| | | | | | | | - Ian Loke
- Glenfield Hospital, Leicester, UK
| | | | | | | | - Tim R Betts
- Oxford Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | | | - Amir Zaidi
- Manchester Heart Centre, Manchester Royal Infirmary, Manchester, UK
| | | | | | - Ashish Patwala
- University Hospital of North Staffordshire, Stoke-on-Trent, UK
| | | | - Stephen Pettit
- Royal Papworth Hospital NHS Foundation Trust, Cambridge, UK
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Dowling K, Colling A, Walters H, Chandrasekaran B, Rimington H. Piloting structured focused TTE in outpatients during the COVID-19 pandemic: 'old habits die hard'. Br J Cardiol 2021; 28:50. [PMID: 35747070 PMCID: PMC9063706 DOI: 10.5837/bjc.2021.050] [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] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Transthoracic echocardiography presents a risk of COVID-19 transmission between an echocardiographer and the patient. Reducing the scanning time is likely to mitigate this risk for them both. British Society of Echocardiography (BSE) level 1 echocardiography offers a potential framework for focused scanning in an outpatient setting. There were 116 outpatients scheduled for a level 1 scan supplemented with additional predefined views, if required. Unexpectedly, a fifth of the scans were performed as an unintended full scan for a variety of reasons. Our results showed that focused scans were performed more quickly than full scans and below the NHS Test and Trace exposure cut-off of 15 minutes. However, if more than three sets of additional measurements were required then a full scan could be performed more quickly. Seniority of the echocardiographer and scan time had an inverse relationship. By examining the patients' clinical records we were confident that all of the scans, whether focused or full, had answered the requestor's clinical question. Although the COVID-19 vaccination programme should reduce the necessity of minimising exposure time during a scan there could still be a role for level 1 scanning during the COVID-19 recovery programme to tackle the vast lists of patients waiting for an echocardiogram.
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Affiliation(s)
- Kay Dowling
- Clinical Scientist Wiltshire Cardiac Centre, Great Western Hospital, Swindon, SN3 6BB
| | - Amanda Colling
- Chief Clinical Physiologist Wiltshire Cardiac Centre, Great Western Hospital, Swindon, SN3 6BB
| | - Harriet Walters
- Clinical Scientist Wiltshire Cardiac Centre, Great Western Hospital, Swindon, SN3 6BB
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Azharuddin S, Rao CR, Chandrasekaran B, Pedersen S. Effects of Prolonged Sitting Interventions on Chronic Low-Grade Inflammation in Adults: a Protocol for a Systematic Review. Muscles Ligaments Tendons J 2021. [DOI: 10.32098/mltj.04.2021.02] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- S. Azharuddin
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Chythra R. Rao
- Department of Community Medicine, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - B. Chandrasekaran
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - S.J. Pedersen
- Active Work Laboratory, School of Education, University of Tasmania, Tasmania, Australia
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10
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Woodward W, Dockerill C, McCourt A, Upton R, O'Driscoll J, Balkhausen K, Chandrasekaran B, Firoozan S, Kardos A, Wong K, Woodward G, Sarwar R, Sabharwal N, Benedetto E, Spagou N, Sharma R, Augustine D, Tsiachristas A, Senior R, Leeson P, Boardman H, d'Arcy J, Abraheem A, Banypersad S, Boos C, Bulugahapitiya S, Butts J, Coles D, Easaw J, Hamdan H, Jamil-Copley S, Kanaganayagam G, Mwambingu T, Pantazis A, Papachristidis A, Rajani R, Rasheed MA, Razvi NA, Rekhraj S, Ripley DP, Rose K, Scheuermann-Freestone M, Schofield R, Sultan A. Real-world performance and accuracy of stress echocardiography: the EVAREST observational multi-centre study. Eur Heart J Cardiovasc Imaging 2021; 23:689-698. [PMID: 34148078 PMCID: PMC9016358 DOI: 10.1093/ehjci/jeab092] [Citation(s) in RCA: 3] [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] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/04/2021] [Indexed: 12/22/2022] Open
Abstract
Aims Stress echocardiography is widely used to identify obstructive coronary artery disease (CAD). High accuracy is reported in expert hands but is dependent on operator training and image quality. The EVAREST study provides UK-wide data to evaluate real-world performance and accuracy of stress echocardiography. Methods and results Participants undergoing stress echocardiography for CAD were recruited from 31 hospitals. Participants were followed up through health records which underwent expert adjudication. Cardiac outcome was defined as anatomically or functionally significant stenosis on angiography, revascularization, medical management of ischaemia, acute coronary syndrome, or cardiac-related death within 6 months. A total of 5131 patients (55% male) participated with a median age of 65 years (interquartile range 57–74). 72.9% of studies used dobutamine and 68.5% were contrast studies. Inducible ischaemia was present in 19.3% of scans. Sensitivity and specificity for prediction of a cardiac outcome were 95.4% and 96.0%, respectively, with an accuracy of 95.9%. Sub-group analysis revealed high levels of predictive accuracy across a wide range of patient and protocol sub-groups, with the presence of a resting regional wall motion abnormalitiy significantly reducing the performance of both dobutamine (P < 0.01) and exercise (P < 0.05) stress echocardiography. Overall accuracy remained consistently high across all participating hospitals. Conclusion Stress echocardiography has high accuracy across UK-based hospitals and thus indicates stress echocardiography is being delivered effectively in real-world practice, reinforcing its role as a first-line investigation in the assessment of patients with stable chest pain.
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Affiliation(s)
- William Woodward
- Cardiovascular Clinical Research Facility, RDM Division of Cardiovascular Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Cameron Dockerill
- Cardiovascular Clinical Research Facility, RDM Division of Cardiovascular Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Annabelle McCourt
- Cardiovascular Clinical Research Facility, RDM Division of Cardiovascular Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Ross Upton
- Cardiovascular Clinical Research Facility, RDM Division of Cardiovascular Medicine, University of Oxford, Oxford OX3 9DU, UK.,Ultromics Ltd, Wood Centre for Innovation, OxfordOX3 8SB, UK
| | - Jamie O'Driscoll
- Department of Cardiology, St George's University Hospitals NHS Foundation Trust, London SW17 0QT, UK.,School of Human and Life Sciences, Canterbury Christ Church University, Canterbury CT1 1QU, UK
| | - Katrin Balkhausen
- Department of Cardiology, Royal Berkshire Hospitals NHS Foundation Trust, Reading RG1 5AN, UK
| | | | - Soroosh Firoozan
- Department of Cardiology, Buckinghamshire Healthcare NHS Trust, High Wycombe HP11 2TT, UK
| | - Attila Kardos
- Department of Cardiology, Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes MK6 5LD, UK
| | - Kenneth Wong
- Lancashire Cardiac Centre, Blackpool Teaching Hospitals NHS Foundation Trust, Blackpool FY3 8NP, UK
| | - Gary Woodward
- Ultromics Ltd, Wood Centre for Innovation, OxfordOX3 8SB, UK
| | - Rizwan Sarwar
- Ultromics Ltd, Wood Centre for Innovation, OxfordOX3 8SB, UK.,Oxford Heart Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, OX3 9DU, UK
| | - Nikant Sabharwal
- Oxford Heart Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, OX3 9DU, UK
| | - Elena Benedetto
- Cardiovascular Clinical Research Facility, RDM Division of Cardiovascular Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Nancy Spagou
- Ultromics Ltd, Wood Centre for Innovation, OxfordOX3 8SB, UK
| | - Rajan Sharma
- Department of Cardiology, St George's University Hospitals NHS Foundation Trust, London SW17 0QT, UK
| | - Daniel Augustine
- Department of Cardiology, Royal United Hospitals NHS Foundation Trust, Bath, BA1 3NG, UK
| | - Apostolos Tsiachristas
- Health Economic Research Centre, Nuffield Department of Population Health, University of Oxford, Oxford OX3 7LF, UK
| | - Roxy Senior
- National Heart and Lung Institute, Imperial College London, London SW3 6LY, UK.,Department of Cardiology, Royal Brompton and Harefield NHS Foundation Trust, London SW3 6NJ, UK.,Department of Cardiology, London North West University Healthcare NHS Trust, London HA1 3UJ, UK
| | - Paul Leeson
- Cardiovascular Clinical Research Facility, RDM Division of Cardiovascular Medicine, University of Oxford, Oxford OX3 9DU, UK
| | - Henry Boardman
- Department of Cardiology, Milton Keynes University Hospital NHS Foundation Trust, Milton Keynes MK6 5LD, UK.,Oxford Heart Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, OX3 9DU, UK
| | - Joanna d'Arcy
- Oxford Heart Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, OX3 9DU, UK
| | - Abraheem Abraheem
- Department of Cardiology, Tameside and Glossop Integrated Care NHS Foundation Trust, Ashton-under-Lyne, UK
| | - Sanjay Banypersad
- Department of Cardiology, East Lancashire Hospitals NHS Trust, Burnley, UK
| | - Christopher Boos
- Department of Cardiology, Poole Hospital NHS Foundation Trust, Poole, UK
| | | | - Jeremy Butts
- Department of Cardiology, Calderdale and Huddersfield NHS Foundation Trust, Calderdale, UK
| | - Duncan Coles
- Department of Cardiology, Mid Essex NHS Hospital Services NHS Trust, Broomfield, UK
| | - Jacob Easaw
- Department of Cardiology, Royal United Hospitals NHS Foundation Trust, Bath, BA1 3NG, UK
| | - Haytham Hamdan
- Department of Cardiology, Wrightington, Wigan and Leigh NHS Foundation Trust, Wigan, UK
| | - Shahnaz Jamil-Copley
- Department of Cardiology, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Gajen Kanaganayagam
- Department of Cardiology, Chelsea and Westminster Hospital NHS Foundation Trust, London, UK
| | - Tom Mwambingu
- Department of Cardiology, The Mid Yorkshire Hospitals NHS Trust, Pinderfields, UK
| | - Antonis Pantazis
- Department of Cardiology, North Middlesex University Hospital NHS Trust, London, UK
| | | | - Ronak Rajani
- Department of Cardiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | | | - Naveed A Razvi
- Department of Cardiology, East Suffolk and North Essex NHS Foundation Trust, Ipswich, UK
| | - Sushma Rekhraj
- Department of Cardiology, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - David P Ripley
- Department of Cardiology, Northumbria Healthcare NHS Foundation Trust, North Tyneside, UK
| | - Kathleen Rose
- Department of Cardiology, Northampton General Hospital NHS Trust, Northampton, UK
| | | | - Rebecca Schofield
- Department of Cardiology, North West Anglia NHS Foundation Trust, Peterborough, UK
| | - Ayyaz Sultan
- Department of Cardiology, Wrightington, Wigan and Leigh NHS Foundation Trust, Wigan, UK
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Bommasamudram T, Gandhi P, Iype RO, Raj B, Chandrasekaran B. Circadian influence on post-exercise hypotension: a review. Comparative Exercise Physiology 2021. [DOI: 10.3920/cep200051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Circadian rhythm (CR) can influence the physiological and psychological parameters in every individual. There is a sinusoidal response to blood pressure brought about by the CR. A drop in blood pressure response immediately after an exercise is termed as post-exercise hypotension (PEH). The objective of the present paper is to review the influence of CR on PEH. Comparing the types of exercises, aerobic training showed a higher magnitude of the drop in PEH than resistance training. However, the majority of the studies have not considered the CR influence on PEH. With the evidence available, we can conclude that morning exercise shows the higher magnitude of the drop in PEH and could be sustained for a longer duration.
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Affiliation(s)
- T. Bommasamudram
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Marena, Manipal, Udupi 576104, Karnataka, India
| | - P. Gandhi
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Marena, Manipal, Udupi 576104, Karnataka, India
| | - R. Oommen Iype
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Marena, Manipal, Udupi 576104, Karnataka, India
| | - B. Raj
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Marena, Manipal, Udupi 576104, Karnataka, India
| | - B. Chandrasekaran
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Marena, Manipal, Udupi 576104, Karnataka, India
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12
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Helliwell H, Desai A, McCole M, Beale A, Ramadurai G, Chandrasekaran B, Yiin GS. The importance of early completion of cardiac investigations after ischaemic stroke: a case and systematic review of reperfusion therapy in stroke due to cardiac fibroelastoma. Clin Med (Lond) 2021; 20:597-599. [PMID: 33199328 DOI: 10.7861/clinmed.2020-0763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | | | | | - Andy Beale
- Great Western Hospitals NHS Foundation Trust, Swindon, UK
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13
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Tulasiram B, Chandrasekaran B. Are Smartphones Better in Guiding Physical Activity Among Sedentary Young Adults? A Randomised Controlled Trial. Muscles Ligaments Tendons J 2021. [DOI: 10.32098/mltj.01.2021.10] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- B. Tulasiram
- Centre for Sports Science, Medicine and Research, School of Allied Health Sciences, Manipal Academy of Higher Education, Karnataka, India
| | - B. Chandrasekaran
- Centre for Sports Science, Medicine and Research, School of Allied Health Sciences, Manipal Academy of Higher Education, Karnataka, India
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14
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Zongpa T, Chandrasekaran B, Arumugam A. Effectiveness of A Smartphone Directed Physical Activity Program on Cardiometabolic Disease Risk in Desk Based Office Employees. A Pragmatic, Two Arm, Parallel, Cluster Randomised Trial. Muscles Ligaments Tendons J 2020. [DOI: 10.32098/mltj.04.2020.19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- T.C. Zongpa
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - B. Chandrasekaran
- Department of Exercise and Sports Sciences, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - A. Arumugam
- Department of Physiotherapy, College of Health Sciences, University of Sharjah, Sharjah, United Arab Emirates
- Department of Physiotherapy, Adjunct Faculty, Manipal College of Health Professions, Manipal Academy of Higher Education, Manipal, Karnataka, India
- Department of Physiotherapy, Adjunct Faculty, Universitas Binawan, Indonesia
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15
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Affiliation(s)
- Andrew J M Lewis
- 1 Department of Cardiology Great Western Hospitals NHS Foundation Trust Swindon United Kingdom.,2 Radcliffe Department of Medicine and British Heart Centre for Research Excellence John Radcliffe Hospital University of Oxford United Kingdom
| | - Paul Foley
- 1 Department of Cardiology Great Western Hospitals NHS Foundation Trust Swindon United Kingdom
| | - Zachary Whinnett
- 3 Imperial College London Hammersmith Hospital London United Kingdom
| | - Daniel Keene
- 3 Imperial College London Hammersmith Hospital London United Kingdom
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16
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17
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Keene D, Arnold AD, Jastrzębski M, Burri H, Zweibel S, Crespo E, Chandrasekaran B, Bassi S, Joghetaei N, Swift M, Moskal P, Francis DP, Foley P, Shun-Shin MJ, Whinnett ZI. His bundle pacing, learning curve, procedure characteristics, safety, and feasibility: Insights from a large international observational study. J Cardiovasc Electrophysiol 2019; 30:1984-1993. [PMID: 31310403 PMCID: PMC7038224 DOI: 10.1111/jce.14064] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/01/2019] [Accepted: 07/07/2019] [Indexed: 11/28/2022]
Abstract
Background His‐bundle pacing (HBP) provides physiological ventricular activation. Observational studies have demonstrated the techniques’ feasibility; however, data have come from a limited number of centers. Objectives We set out to explore the contemporary global practice in HBP focusing on the learning curve, procedural characteristics, and outcomes. Methods This is a retrospective, multicenter observational study of patients undergoing attempted HBP at seven centers. Pacing indication, fluoroscopy time, HBP thresholds, and lead reintervention and deactivation rates were recorded. Where centers had systematically recorded implant success rates from the outset, these were collated. Results A total of 529 patients underwent attempted HBP during the study period (2014‐19) with a mean follow‐up of 217 ± 303 days. Most implants were for bradycardia indications. In the three centers with the systematic collation of all attempts, the overall implant success rate was 81%, which improved to 87% after completion of 40 cases. All seven centers reported data on successful implants. The mean fluoroscopy time was 11.7 ± 12.0 minutes, the His‐bundle capture threshold at implant was 1.4 ± 0.9 V at 0.8 ± 0.3 ms, and it was 1.3 ± 1.2 V at 0.9 ± 0.2 ms at last device check. HBP lead reintervention or deactivation (for lead displacement or rise in threshold) occurred in 7.5% of successful implants. There was evidence of a learning curve: fluoroscopy time and HBP capture threshold reduced with greater experience, plateauing after approximately 30‐50 cases. Conclusion We found that it is feasible to establish a successful HBP program, using the currently available implantation tools. For physicians who are experienced at pacemaker implantation, the steepest part of the learning curve appears to be over the first 30‐50 cases.
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Affiliation(s)
- Daniel Keene
- National Heart and Lung Institute, Imperial College London, London
| | - Ahran D Arnold
- National Heart and Lung Institute, Imperial College London, London
| | - Marek Jastrzębski
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, Jagiellonian University Collegium Medicum, Krakow, Poland
| | - Haran Burri
- Department of Cardiology, University Hospital, Cardiology, Geneva, Switzerland
| | - Steven Zweibel
- Department of Interventional Electrophysiology, Hartford Hospital, Interventional Electrophysiology, Hartford
| | - Eric Crespo
- Department of Interventional Electrophysiology, Hartford Hospital, Interventional Electrophysiology, Hartford
| | | | - Sukhbinder Bassi
- Cardiology Department, Sherwood Forest Hospitals NHS Foundation Trust, Sutton, Ashfield
| | - Nader Joghetaei
- Department of Cardiology, Klinikum Landkreis Erding, Cardiology, Munich, Germany
| | - Matthew Swift
- Cardiology Department, Great Western Hospitals NHS Foundation Trust, Swindon
| | - Pawel Moskal
- First Department of Cardiology, Interventional Electrocardiology and Hypertension, Jagiellonian University Collegium Medicum, Krakow, Poland
| | - Darrel P Francis
- National Heart and Lung Institute, Imperial College London, London
| | - Paul Foley
- Cardiology Department, Great Western Hospitals NHS Foundation Trust, Swindon
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18
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Zivlas C, Ramcharitar S, Chandrasekaran B. Streptococcus sanguinis Endocarditis Involving All Valves in a Patient with Ventricular Septal Defect. J Cardiovasc Ultrasound 2017; 25:105-106. [PMID: 29093773 PMCID: PMC5658290 DOI: 10.4250/jcu.2017.25.3.105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 06/30/2017] [Accepted: 09/01/2017] [Indexed: 11/22/2022] Open
Affiliation(s)
- Christos Zivlas
- Wiltshire Cardiac Centre, Great Western Hospital, Swindon, UK
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19
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Philippsen T, Orini M, Martin C, Volkova E, Ormerod J, Sohaib S, Elamin N, Blake S, Sawhney V, Ahmad S, Waring O, Bowers R, Raiman L, Hazelwood T, Mills R, Corrado C, Honarbakhsh S, Von Maydell A, Norrish G, Chubb H, Chubb H, Chubb H, Toledano M, Ruiz A, van Zalen J, Foley P, Pearman C, Rehal O, Foley P, Wong L, Foley P, Pearman C, Brahmbhatt D, Khan H, Wardley J, Akbar S, Christensen L, Hansen M, Brandes A, Tinker A, Munroe P, Lambiase P, Honarbakhsh S, McLean A, Lambiase P, Schilling R, Lane J, Chow A, Earley M, Hunter R, Khan F, Lambiase P, Schilling R, Sporton S, Dhinoja M, Camm C, Xavier R, de Sousa M, Betts T, Shun-Shin M, Wright I, Lim E, Lim P, Koawing M, Lefroy D, Linton N, Davies D, Peters N, Kanagaratnam P, Francis D, Whinnett Z, Khan M, Bowes R, Sahu J, Sheridan P, Rogers D, Kyriacou A, Kelland N, Lewis N, Lee J, Segall E, Diab I, Breitenstein A, Ullah W, Sporton S, Earley M, Finlay M, Dhinoja M, Schilling R, Hunter R, Ahmed M, Petkar S, Davidson N, Stout M, Pearce KP, Leo M, Ginks M, Rajappan K, Bashir Y, Balasubramaniam R, Sopher S, Betts T, Paisey J, Cheong J, Roy D, Adhya S, Williams S, O'Neill M, Niederer S, Providencia R, Srinivasan N, Ahsan S, Lowe M, Segal O, Hunter R, Finlay M, Earley M, Schilling R, Lambiase P, Stella S, Cantwell C, Chowdhury R, Kim S, Linton N, Whinnett Z, Koa-Wing M, Lefroy D, Davies DW, Kanagaratnam P, Lim PB, Qureshi N, Peters N, Cantarutti N, Limongelli G, Elliott P, Kaski J, Williams S, Lal K, Harrison J, Whitaker J, Kiedrowicz R, Wright M, O'Neill M, Harrison J, Whitaker J, Williams S, Wright M, Schaeffter T, Razavi R, O'Neill M, Karim R, Williams S, Harrison J, Whitaker J, Wright M, Schaeffter T, Razavi R, O'Neill M, Montanes M, Ella Field E, Walsh H, Callaghan N, Till J, Mangat J, Lowe M, Kaski J, Ruiz Duthil A, Li A, Saba M, Patel N, Beale L, Brickley G, Lloyd G, French A, Khavandi A, McCrea W, Barnes E, Chandrasekaran B, Parry J, Garth L, Chapman J, Todd D, Hobbs J, Modi S, Waktare J, Hall M, Gupta D, Snowdon R, Papageorgiou N, Providência R, Falconer D, Sewart E, Ahsan S, Segal O, Ezzat V, Rowland E, Lowe M, Lambiase P, Chow A, Swift M, Charlton P, James J, Colling A, Barnes E, Starling L, Kontogeorgis A, Roses-Noguer F, Wong T, Jarman J, Clague J, Till J, Colling A, James J, Hawkins M, Burnell S, Chandrasekaran B, Coulson J, Smith L, Choudhury M, Oguguo E, Boyett M, Morris G, Flinn W, Chari A, Belham M, Pugh P, Somarakis K, Parasa R, Allata A, Hashim H, Mathew T, Kayasundar S, Venables P, Quinn J, Ivanova J, Brown S, Oliver R, Lyons M, Chuen M, Walsh J, Robinson T, Staniforth A, Ahsan A, Jamil-Copley S. POSTERS (2)96CONTINUOUS VERSUS INTERMITTENT MONITORING FOR DETECTION OF SUBCLINICAL ATRIAL FIBRILLATION IN HIGH-RISK PATIENTS97HIGH DAY-TO-DAY INTRA-INDIVIDUAL REPRODUCIBILITY OF THE HEART RATE RESPONSE TO EXERCISE IN THE UK BIOBANK DATA98USE OF NOVEL GLOBAL ULTRASOUND IMAGING AND CONTINUEOUS DIPOLE DENSITY MAPPING TO GUIDE ABLATION IN MACRO-REENTRANT TACHYCARDIAS99ANTICOAGULATION AND THE RISK OF COMPLICATIONS IN PATIENTS UNDERGOING VT AND PVC ABLATION100NON-SUSTAINED VENTRICULAR TACHYCARDIA FREQUENTLY PRECEDES CARDIAC ARREST IN PATIENTS WITH BRUGADA SYNDROME101USING HIGH PRECISION HAEMODYNAMIC MEASUREMENTS TO ASSESS DIFFERENCES IN AV OPTIMUM BETWEEN DIFFERENT LEFT VENTRICULAR LEAD POSITIONS IN BIVENTRICULAR PACING102CAN WE PREDICT MEDIUM TERM MORTALITY FROM TRANSVENOUS LEAD EXTRACTION PRE-OPERATIVELY?103PREVENTION OF UNECESSARY ADMISSIONS IN ATRIAL FIBRILLATION104EPICARDIAL CATHETER ABLATION FOR VENTRICULAR TACHYCARDIA ON UNINTERRUPTED WARFARIN: A SAFE APPROACH?105HOW WELL DOES THE NATIONAL INSTITUTE OF CLINICAL EXCELLENCE (NICE) GUIDENCE ON TRANSIENT LOSS OF CONSCIOUSNESS (T-LoC) WORK IN A REAL WORLD? AN AUDIT OF THE SECOND STAGE SPECIALIST CARDIOVASCULAT ASSESSMENT AND DIAGNOSIS106DETECTION OF ATRIAL FIBRILLATION IN COMMUNITY LOCATIONS USING NOVEL TECHNOLOGY'S AS A METHOD OF STROKE PREVENTION IN THE OVER 65'S ASYMPTOMATIC POPULATION - SHOULD IT BECOME STANDARD PRACTISE?107HIGH-DOSE ISOPRENALINE INFUSION AS A METHOD OF INDUCTION OF ATRIAL FIBRILLATION: A MULTI-CENTRE, PLACEBO CONTROLLED CLINICAL TRIAL IN PATIENTS WITH VARYING ARRHYTHMIC RISK108PACEMAKER COMPLICATIONS IN A DISTRICT GENERAL HOSPITAL109CARDIAC RESYNCHRONISATION THERAPY: A TRADE-OFF BETWEEN LEFT VENTRICULAR VOLTAGE OUTPUT AND EJECTION FRACTION?110RAPID DETERIORATION IN LEFT VENTRICULAR FUNCTION AND ACUTE HEART FAILURE AFTER DUAL CHAMBER PACEMAKER INSERTION WITH RESOLUTION FOLLOWING BIVENTRICULAR PACING111LOCALLY PERSONALISED ATRIAL ELECTROPHYSIOLOGY MODELS FROM PENTARAY CATHETER MEASUREMENTS112EVALUATION OF SUBCUTANEOUS ICD VERSUS TRANSVENOUS ICD- A PROPENSITY MATCHED COST-EFFICACY ANALYSIS OF COMPLICATIONS & OUTCOMES113LOCALISING DRIVERS USING ORGANISATIONAL INDEX IN CONTACT MAPPING OF HUMAN PERSISTENT ATRIAL FIBRILLATION114RISK FACTORS FOR SUDDEN CARDIAC DEATH IN PAEDIATRIC HYPERTROPHIC CARDIOMYOPATHY: A SYSTEMATIC REVIEW AND META-ANALYSIS115EFFECT OF CATHETER STABILITY AND CONTACT FORCE ON VISITAG DENSITY DURING PULMONARY VEIN ISOLATION116HEPATIC CAPSULE ENHANCEMENT IS COMMONLY SEEN DURING MR-GUIDED ABLATION OF ATRIAL FLUTTER: A MECHANISTIC INSIGHT INTO PROCEDURAL PAIN117DOES HIGHER CONTACT FORCE IMPAIR LESION FORMATION AT THE CAVOTRICUSPID ISTHMUS? INSIGHTS FROM MR-GUIDED ABLATION OF ATRIAL FLUTTER118CLINICAL CHARACTERISATION OF A MALIGNANT SCN5A MUTATION IN CHILDHOOD119RADIOFREQUENCY ASSOCIATED VENTRICULAR FIBRILLATION120CONTRACTILE RESERVE EXPRESSED AS SYSTOLIC VELOCITY DOES NOT PREDICT RESPONSE TO CRT121DAY-CASE DEVICES - A RETROSPECTIVE STUDY USING PATIENT CODING DATA122PATIENTS UNDERGOING SVT ABLATION HAVE A HIGH INCIDENCE OF SECONDARY ARRHYTHMIA ON FOLLOW UP: IMPLICATIONS FOR PRE-PROCEDURE COUNSELLING123PROGNOSTIC ROLE OF HAEMOGLOBINN AND RED BLOOD CELL DITRIBUTION WIDTH IN PATIENTS WITH HEART FAILURE UNDERGOING CARDIAC RESYNCHRONIZATION THERAPY124REMOTE MONITORING AND FOLLOW UP DEVICES125A 20-YEAR, SINGLE-CENTRE EXPERIENCE OF IMPLANTABLE CARDIOVERTER DEFIBRILLATORS (ICD) IN CHILDREN: TIME TO CONSIDER THE SUBCUTANEOUS ICD?126EXPERIENCE OF MAGNETIC REASONANCE IMAGING (MEI) IN PATIENTS WITH MRI CONDITIONAL DEVICES127THE SINUS BRADYCARDIA SEEN IN ATHLETES IS NOT CAUSED BY ENHANCED VAGAL TONE BUT INSTEAD REFLECTS INTRINSIC CHANGES IN THE SINUS NODE REVEALED BY
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(F) BLOCKADE128SUCCESSFUL DAY-CASE PACEMAKER IMPLANTATION - AN EIGHT YEAR SINGLE-CENTRE EXPERIENCE129LEFT VENTRICULAR INDEX MASS ASSOCIATED WITH ESC HYPERTROPHIC CARDIOMYOPATHY RISK SCORE IN PATIENTS WITH ICDs: A TERTIARY CENTRE HCM REGISTRY130A DGH EXPERIENCE OF DAY-CASE CARDIAC PACEMAKER IMPLANTATION131IS PRE-PROCEDURAL FASTING A NECESSITY FOR SAFE PACEMAKER IMPLANTATION? Europace 2016. [DOI: 10.1093/europace/euw274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Green PG, French AE, Petrou M, Manghat NE, Lyen SM, Chandrasekaran B. Mitral Valve Diverticulum Presenting with Severe Mitral Stenosis: Case Report. J Heart Valve Dis 2016; 25:515-518. [PMID: 28009962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The case is presented of a non-infectious anterior mitral valve leaflet diverticulum, which appeared as symptomatic mitral stenosis. Unlike previous reports, there was no histological myxomatous degeneration of the valve. To the authors' knowledge, this is the first time a mitral valve diverticulum resulting in severe mitral stenosis has been reported in the literature.
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Affiliation(s)
| | | | - Mario Petrou
- Department of Cardiothoracic Surgery, John Radcliffe Hospital, Oxford, UK
| | | | - Stephen M Lyen
- Department of Radiology, Bristol Heart Institute, Bristol, UK
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Akula KK, Chandrasekaran B, Kaur M, Kulkarni SK. Development and Validation of a Specific RP-HPLC Method for the Estimation of γ-Aminobutyric Acid in Rat Brain Tissue Samples Using Benzoyl Chloride Derivatization and PDA Detection. ACTA CHROMATOGR 2015. [DOI: 10.1556/achrom.27.2015.3.2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Harries I, Chandrasekaran B, Barnes E, Ramcharitar S. Iatrogenic mitral stenosis following transcatheter aortic valve replacement (TAVR). Indian Heart J 2015; 67:60-1. [PMID: 25820053 DOI: 10.1016/j.ihj.2015.02.005] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/03/2015] [Indexed: 10/23/2022] Open
Abstract
A 57 year old female underwent transcatheter aortic valve replacement (TAVR) for severe aortic stenosis. Mild iatrogenic mitral stenosis was noted intraoperatively. Attempts to reposition the device were hampered by aortic angulation. One year later, severe mitral stenosis was confirmed on transoesophageal echocardiography. It is important to recognise that iatorgenic mitral stenosis due to TAVR may progress over time. Care should be taken to minimise the risk of this rare complication.
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Affiliation(s)
- Iwan Harries
- Wiltshire Cardiac Centre, Great Western Hospital, Marlborough Road, Swindon, Wiltshire SN3 6BB, UK
| | | | - Edward Barnes
- Wiltshire Cardiac Centre, Great Western Hospital, Marlborough Road, Swindon, Wiltshire SN3 6BB, UK
| | - Steve Ramcharitar
- Wiltshire Cardiac Centre, Great Western Hospital, Marlborough Road, Swindon, Wiltshire SN3 6BB, UK.
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23
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Sundarapandiyan S, Renitha TS, Sridevi J, Chandrasekaran B, Saravanan P, Raju GB. Mechanistic insight into active chlorine species mediated electrochemical degradation of recalcitrant phenolic polymers. RSC Adv 2014. [DOI: 10.1039/c4ra09069a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Degradation of recalcitrant phenolic syntan by electro-oxidation was investigated. The kinetics of mineralization of phenolic syntan was followed both in terms of TOC and COD measurements.
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Affiliation(s)
- S. Sundarapandiyan
- National Metallurgical Laboratory (Council of Scientific & Industrial Research, New Delhi)
- Chennai 600 113, India
| | - T. Shiny Renitha
- Central Leather Research Institute (Council of Scientific & Industrial Research, New Delhi)
- Chennai 600 020, India
| | - J. Sridevi
- Central Leather Research Institute (Council of Scientific & Industrial Research, New Delhi)
- Chennai 600 020, India
| | - B. Chandrasekaran
- Central Leather Research Institute (Council of Scientific & Industrial Research, New Delhi)
- Chennai 600 020, India
| | - P. Saravanan
- Central Leather Research Institute (Council of Scientific & Industrial Research, New Delhi)
- Chennai 600 020, India
| | - G. Bhaskar Raju
- National Metallurgical Laboratory (Council of Scientific & Industrial Research, New Delhi)
- Chennai 600 113, India
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Usharani N, Jayakumar GC, Rao JR, Chandrasekaran B, Nair BU. A microscopic evaluation of collagen-bilirubin interactions: in vitro surface phenomenon. J Microsc 2013; 253:109-18. [PMID: 24329396 DOI: 10.1111/jmi.12101] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [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: 05/06/2013] [Accepted: 10/17/2013] [Indexed: 11/29/2022]
Abstract
This study is carried out to understand the morphology variations of collagen I matrices influenced by bilirubin. The characteristics of bilirubin interaction with collagen ascertained using various techniques like XRD, CLSM, fluorescence, SEM and AFM. These techniques are used to understand the distribution, expression and colocalization patterns of collagen-bilirubin complexes. The present investigation mimic the in vivo mechanisms created during the disorder condition like jaundice. Fluorescence technique elucidates the crucial role played by bilirubin deposition and interaction during collagen organization. Influence of bilirubin during collagen fibrillogenesis and banding patterns are clearly visualize using SEM. As a result, collagen-bilirubin complex provides different reconstructed patterns because of the influence of bilirubin concentration. Selectivity, specificity and spatial organization of collagen-bilirubin are determined through AFM imaging. Consequently, it is observed that the morphology and quantity of the bilirubin binding to collagen varied by the concentrations and the adsorption rate in protein solutions. Microscopic studies of collagen-bilirubin interaction confirms that bilirubin influence the fibrillogenesis and alter the rate of collagen organization depending on the bilirubin concentration. This knowledge helps to develop a novel drug to inhibit the interface point of interaction between collagen and bilirubin.
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Affiliation(s)
- N Usharani
- CSIR-Central Leather Research Institute, Council of Scientific and Industrial Research, Adyar, Chennai, 600 020, India
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Banerjee B, Chandrasekaran B. A Constraint Satisfaction Framework for Executing Perceptions and Actions in Diagrammatic Reasoning. J ARTIF INTELL RES 2010. [DOI: 10.1613/jair.3069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Diagrammatic reasoning (DR) is pervasive in human problem solving as a powerful adjunct to symbolic reasoning based on language-like representations. The research reported in this paper is a contribution to building a general purpose DR system as an extension to a SOAR-like problem solving architecture. The work is in a framework in which DR is modeled as a process where subtasks are solved, as appropriate, either by inference from symbolic representations or by interaction with a diagram, i.e., perceiving specified information from a diagram or modifying/creating objects in a diagram in specified ways according to problem solving needs. The perceptions and actions in most DR systems built so far are hand-coded for the specific application, even when the rest of the system is built using the general architecture. The absence of a general framework for executing perceptions/actions poses as a major hindrance to using them opportunistically -- the essence of open-ended search in problem solving.
Our goal is to develop a framework for executing a wide variety of specified perceptions and actions across tasks/domains without human intervention. We observe that the domain/task-specific visual perceptions/actions can be transformed into domain/task-independent spatial problems. We specify a spatial problem as a quantified constraint satisfaction problem in the real domain using an open-ended vocabulary of properties, relations and actions involving three kinds of diagrammatic objects -- points, curves, regions. Solving a spatial problem from this specification requires computing the equivalent simplified quantifier-free expression, the complexity of which is inherently doubly exponential. We represent objects as configuration of simple elements to facilitate decomposition of complex problems into simpler and similar subproblems. We show that, if the symbolic solution to a subproblem can be expressed concisely, quantifiers can be eliminated from spatial problems in low-order polynomial time using similar previously solved subproblems. This requires determining the similarity of two problems, the existence of a mapping between them computable in polynomial time, and designing a memory for storing previously solved problems so as to facilitate search. The efficacy of the idea is shown by time complexity analysis. We demonstrate the proposed approach by executing perceptions and actions involved in DR tasks in two army applications.
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Chandrasekaran B, Chan AHD, Wong PCM. Neural Integration of Lexical and Indexical Information in Spoken Language Processing. Neuroimage 2009. [DOI: 10.1016/s1053-8119(09)71747-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Chandrasekharan H, Sarangi A, Nagarajan M, Singh VP, Rao DUM, Stalin P, Natarajan K, Chandrasekaran B, Anbazhagan S. Variability of soil-water quality due to Tsunami-2004 in the coastal belt of Nagapattinam district, Tamilnadu. J Environ Manage 2008; 89:63-72. [PMID: 17531371 DOI: 10.1016/j.jenvman.2007.01.051] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 09/23/2006] [Accepted: 01/15/2007] [Indexed: 05/15/2023]
Abstract
In this study, the Tsunami-caused deterioration of soil and groundwater quality in the agricultural fields of coastal Nagapattinam district of Tamilnadu state in India is presented by analyzing their salinity and sodicity parameters. To accomplish this, three sets of soil samples up to a depth of 30 cm from the land surface were collected for the first six months of the year 2005 from 28 locations and the ground water samples were monitored from seven existing dug wells and hand pumps covering the study region at intervals of 3 months. The EC and pH values of both the soil and ground water samples were estimated and the spatial and temporal variability mappings of these parameters were performed using the geostatistical analysis module of ArcGIS((R)). It was observed that the spherical semivariogram fitted well with the data set of both EC and pH and the generated kriged maps explained the spatial and temporal variability under different ranges of EC and pH values. Further, the recorded EC and pH data of soil and ground water during pre-Tsunami periods were compared with the collected data and generated variability soil maps of EC and pH of the post-Tsunami period. It was revealed from this analysis that the soil quality six months after the Tsunami was nearing the pre-Tsunami scenario (EC< 1.5 dS m(-1); pH<8), whereas the quality of ground water remained highly saline and unfit for irrigation and drinking. These observations were compared with the ground scenarios of the study region and possible causes for such changes and the remedial measures for taking up regular agricultural practices are also discussed.
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Chandrasekaran B, Dar O, McDonagh T. The role of apelin in cardiovascular function and heart failure. Eur J Heart Fail 2008; 10:725-32. [PMID: 18583184 DOI: 10.1016/j.ejheart.2008.06.002] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Revised: 04/21/2008] [Accepted: 06/04/2008] [Indexed: 12/11/2022] Open
Abstract
Apelin is a novel peptide that acts through the APJ receptor, sharing similarities with the angiotensin II-angiotensin II type 1 receptor pathway. It is a peripheral vasodilator, powerful inotrope and may affect central fluid homeostasis. Animal and human studies suggest that it may play a role in the pathogenesis of heart failure by modulating the harmful effects of angiotensin II. Apelin is reduced in patients with heart failure and up regulated following favourable left ventricular remodelling. It is widely distributed in a number of tissues, mainly restricted to vascular endothelium. This comprehensive review of the literature highlights the important studies that have led to the discovery of apelin and its role in cardiovascular function and heart failure.
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Chandrasekaran B. Echocardiography in Clinical Practice. J R Soc Med 2003. [DOI: 10.1258/jrsm.96.1.48-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Chandrasekaran B. Echocardiography in Clinical Practice. Med Chir Trans 2003. [DOI: 10.1177/014107680309600117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- B Chandrasekaran
- General Hospital Jersey, St Helier, Jersey JE1 3QS, Channel Islands
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Affiliation(s)
- B Chandrasekaran
- Department of Cardiology, London Chest and Homerton Hospitals, London, UK.
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Affiliation(s)
- B Chandrasekaran
- Department of Cardiology, London Chest and Homerton Hospitals, London, UK.
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Chandrasekaran B. Reach Exceeds Grasp: Comments on Frawley's "Control and Cross-Domain Mental Computation: Evidence from Language Breakdown". Comput Intell 2002. [DOI: 10.1111/1467-8640.00179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Miller D, Josephson J, Elsass M, Davis J, Chandrasekaran B. Sharable engineering knowledge databases for intelligent system applications. Comput Chem Eng 1997. [DOI: 10.1016/s0098-1354(97)87482-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Chandrasekaran B, Kute TE, Duch DS. Synchronization of cells in the S phase of the cell cycle by 3'-azido-3'-deoxythymidine: implications for cell cytotoxicity. Cancer Chemother Pharmacol 1995; 35:489-95. [PMID: 7882457 DOI: 10.1007/bf00686833] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The mechanism of synergy between 3'-azido-3'-deoxythymidine (AZT) and anticancer agents was investigated with emphasis on cell-cycle events. Exposure of exponentially growing WiDr human colon carcinoma cells to AZT resulted in synchronization of cells in the S phase of the cell cycle. Following treatment with AZT at 50 or 200 microM, 62% +/- 3% or 82% +/- 4% of the cells were in the S phase as compared with 36% +/- 2% in the control. Bromodeoxyuridine uptake studies revealed that the synchronized cells actively synthesized DNA. At concentrations of up to 200 microM, AZT produced a cytostatic rather than cytotoxic effect as indicated by viability and cell growth measurements. At 200 microM, AZT-induced synchronization was significant (P = < 0.001) after 12 h of drug exposure, reached a maximum at 24 h, and reversed to baseline levels by 72 h even in the continued presence of the drug. This indicates that AZT-induced cytostasis is a transient and reversible effect. The cell-cycle events seen with AZT in WiDr cells were also observed in eight of nine human tumor cell lines tested. Isobologram analysis of WiDr cells preexposed to AZT for 24 h and then exposed to either AZT-5-fluorouracil or AZT-methotrexate for a further 72 h revealed synergy between AZT and the anticancer agents, indicating that AZT-induced synchronization may have therapeutic benefits.
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Affiliation(s)
- B Chandrasekaran
- Division of Cell Biology, Wellcome Research Laboratories, Research Triangle Park, NC 27709
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Victor TJ, Chandrasekaran B, Reuben R. Composite fish culture for mosquito control in rice fields in southern India. Southeast Asian J Trop Med Public Health 1994; 25:522-7. [PMID: 7777919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Composite culture of edible fishes (common carp, Cryprinus carpio; silver carp, Hypopthalmithys molitrix, grass carp, Ctenopharyngodon idella; catla, Catla catla; rohu, Labeo rohita; and mrigal, Cirrhinus mrigala) in rice fields in the Cauvery delta of Tamil Nadu, southern India, resulted in 81.0% reduction in the immature mosquito population of anophelines and 83.5% of culicines. Analysis of fish feces for mosquito larval head capsules showed that common carp and silver carp are effective larvivores. The selective feeding of common carp on culicines and silver carp on anophelines is correlated to their trophic niches. Net profit in the fish-cum-rice fields was 2.5 times greater than fields in which rice alone was cultured. Hence, rice-cum-fish culture can be recommended to the farming community in this area.
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Affiliation(s)
- T J Victor
- Centre for Research in Medical Entomology (ICMR), Madurai, India
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Elkan C, Berenji H, Chandrasekaran B, de Silva C, Attikiouzel Y, Dubois D, Prade H, Smets P, Freksa C, Garcia O, Klir G, Bo Yuan, Mamdani E, Pelletier F, Ruspini E, Turksen B, Vadiee N, Jamshidi M, Pei-Zhuang Wang, Sie-Keng Tan, Shaohua Tan, Yager R, Zadeh L. The paradoxical success of fuzzy logic. ACTA ACUST UNITED AC 1994. [DOI: 10.1109/64.336150] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Stead WW, Haynes RB, Fuller S, Friedman CP, Travis LE, Beck JR, Fenichel CH, Chandrasekaran B, Buchanan BG, Abola EE. Designing medical informatics research and library--resource projects to increase what is learned. J Am Med Inform Assoc 1994; 1:28-33. [PMID: 7719785 PMCID: PMC116182 DOI: 10.1136/jamia.1994.95236134] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Careful study of medical informatics research and library-resource projects is necessary to increase the productivity of the research and development enterprise. Medical informatics research projects can present unique problems with respect to evaluation. It is not always possible to adapt directly the evaluation methods that are commonly employed in the natural and social sciences. Problems in evaluating medical informatics projects may be overcome by formulating system development work in terms of a testable hypothesis; subdividing complex projects into modules, each of which can be developed, tested and evaluated rigorously; and utilizing qualitative studies in situations where more definitive quantitative studies are impractical.
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Affiliation(s)
- W W Stead
- Vanderbilt University, Nashville, TN, USA
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Chandrasekaran B, Kute TE, Capizzi RL. Deoxypyrimidine-induced inhibition of the cytokinetic effects of 1-beta-D-arabinofuranosyluracil. Cancer Chemother Pharmacol 1992; 29:455-60. [PMID: 1568288 DOI: 10.1007/bf00684847] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Ara-U-induced S-phase accumulation and the interaction between high concentrations of ara-U (HiCAU) and ara-C were investigated in L1210 leukemia cells in vitro. Treatment of exponentially growing L1210 murine leukemia cells with ara-U (200-1000 microM) for 48 h caused a dose-dependent accumulation of cells in the S-phase. The extent of this ara-U-induced S-phase accumulation correlated with ara-U incorporation into DNA and with increases of up to 172% and 464% in the specific activities of deoxycytidine kinase and thymidine kinase, respectively, over control values. Metabolism of 1 microM ara-C following the exposure of cells to ara-U (1 mM) resulted in 4.5 pmol araC DNA/mg protein vs 2.1 pmol/mg protein in control cells. Although 48-h exposure of cells to 200 and 400 microM ara-U is not cytotoxic, it enhances the cytotoxicity of ara-C (10-100 microM) 4- to 10-fold. Ara-U-induced S-phase accumulation is inhibited by deoxypyrimidine nucleosides but not by pyrimidine or deoxypurine nucleosides. Some of the ara-U and ara-C concentrations used in this study are achievable in clinical practice, and ara-U/ara-C interactions may explain in part the unique therapeutic utility of high-dose ara-C.
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Affiliation(s)
- B Chandrasekaran
- Comprehensive Cancer Center, Wake Forest University Winston-Salem, NC 27103
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Chandrasekaran B, Swartout W. Explanations in knowledge systems: the role of explicit representation of design knowledge. ACTA ACUST UNITED AC 1991. [DOI: 10.1109/64.87684] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Chandrasekaran B. Models versus rules, deep versus compiled content versus form: some distinctions in knowledge systems research. ACTA ACUST UNITED AC 1991. [DOI: 10.1109/64.79713] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Chandrasekaran B, Capizzi RL, Kute TE, Morgan T, Dimling J. Modulation of the metabolism and pharmacokinetics of 1-beta-D-arabinofuranosylcytosine by 1-beta-D-arabinofuranosyluracil in leukemic mice. Cancer Res 1989; 49:3259-66. [PMID: 2720678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The interaction between high concentrations of 1-beta-D-arabinofuranosyluracil (HiCAU) and 1-beta-D-arabinofuranosylcytosine (ara-C) was investigated in vivo with emphasis on cell kinetics, pharmacokinetics, and drug metabolism. Mice bearing L5178Y leukemia were given a 48-h s.c. infusion of high-dose ara-U (HiDAU) to achieve a plasma level of 0.5 to 1 mM. A total dose of 7.35 g/kg/day for 2 days was nontoxic; the mean survival of control (saline treated) leukemic mice was 12.2 +/- 1.8 days and 11.7 +/- 2.0 days for the HiDAU-treated leukemic mice. Using flow cytometry, cell cycle progression of L5178Y ascites cells was monitored during HiDAU infusion. At 48 h, the proliferative index (PI) percentage of the leukemic cells is significantly different (P less than 0.001) in HiDAU-treated leukemic mice (mean = 50.8) versus control (mean = 45.6). A higher PI percentage is associated with accumulation of cells in S phase. This effect was highly variable in the ara-U-treated mice, and the ara-U "perturbed" group was defined as those mice whose cells had an increase in the PI to greater than or equal to 50%. The higher PI percentage in HiDAU-treated mice correlated with HiCAU in ascites fluid, leukemic cells, and kidney of perturbed mice. HiCAU in the "ara-U-perturbed" group altered the plasma pharmacokinetics of high-dose ara-C (HiDAC, 1 g/kg), increased the cellular metabolism of ara-C to 1-beta-D-arabinofuranosylcytidine triphosphate (ara-CTP) (3-fold), and increased ara-C-DNA synthesis (3-fold). In mice bearing the L5178Y leukemia, a 48-h infusion of ara-U followed by a 24-h s.c. infusion of 40 mg/kg resulted in a 260% increase in life span and seven 90-day survivors among 16 treated mice. In contrast, ara-U or ara-C alone had a negligible therapeutic effect. ara-U-induced alterations in the systemic pharmacokinetics of ara-C are the result of inhibition of cytidine deaminase activity by HiCAU in liver and kidneys. This results in a decrease in ara-C catabolism and prolongs the plasma half-life of ara-C. The dual alteration of the pharmacokinetics of ara-C and cytokinetics of the leukemia cells by HiCAU results in enhanced survival of leukemic mice. These results may help explain the clinical utility of HiDAC treatment programs for patients with acute leukemia.
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Affiliation(s)
- B Chandrasekaran
- Cancer Center of Wake Forest University, Bowman Gray School of Medicine, Winston-Salem, North Carolina 27103
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Bylander T, Chandrasekaran B. Generic tasks for knowledge-based reasoning: the “right” level of abstraction for knowledge acquisition. ACTA ACUST UNITED AC 1987. [DOI: 10.1016/s0020-7373(87)80093-7] [Citation(s) in RCA: 97] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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