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Dive into the research topics where Jayan Parameshwar is active.

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Featured researches published by Jayan Parameshwar.


Journal of Heart and Lung Transplantation | 2010

International Society for Heart and Lung Transplantation working formulation of a standardized nomenclature for cardiac allograft vasculopathy-2010.

Mandeep R. Mehra; María G. Crespo-Leiro; Anne I. Dipchand; Stephan M. Ensminger; Nicola E. Hiemann; J. Kobashigawa; Joren C. Madsen; Jayan Parameshwar; Randall C. Starling; Patricia A. Uber

The development of cardiac allograft vasculopathy remains the Achilles heel of cardiac transplantation. Unfortunately, the definitions of cardiac allograft vasculopathy are diverse, and there are no uniform international standards for the nomenclature of this entity. This consensus document, commissioned by the International Society of Heart and Lung Transplantation Board, is based on best evidence and clinical consensus derived from critical analysis of available information pertaining to angiography, intravascular ultrasound imaging, microvascular function, cardiac allograft histology, circulating immune markers, non-invasive imaging tests, and gene-based and protein-based biomarkers. This document represents a working formulation for an international nomenclature of cardiac allograft vasculopathy, similar to the development of the system for adjudication of cardiac allograft rejection by histology.


British Journal of Haematology | 2010

Diagnosis of post-transplant lymphoproliferative disorder in solid organ transplant recipients – BCSH and BTS Guidelines

Anne Parker; Kristin Bowles; J. Andrew Bradley; Vincent C. Emery; Carrie Featherstone; Girish Gupte; Robert Marcus; Jayan Parameshwar; Alan Ramsay; Charles G. Newstead

A joint working group established by the Haemato‐oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Transplantation Society (BTS) has reviewed the available literature and made recommendations for the diagnosis and management of post‐transplant lymphoproliferative disorder (PTLD) in adult recipients of solid organ transplants. This review details the risk factors predisposing to development, initial features and diagnosis. It is important that the risk of developing PTLD is considered when using post transplant immunosuppression and that the appropriate investigations are carried out when there are suspicions of the diagnosis. These must include tissue for histology and computed tomography scan to assess the extent of disease. These recommendations have been made primarily for adult patients, there have been some comments made with regard to paediatric practice.


British Journal of Haematology | 2010

Management of post-transplant lymphoproliferative disorder in adult solid organ transplant recipients - BCSH and BTS Guidelines

Anne Parker; Kristin Bowles; J. Andrew Bradley; Vincent C. Emery; Carrie Featherstone; Girish Gupte; Robert Marcus; Jayan Parameshwar; Alan Ramsay; Charles G. Newstead

A joint working group established by the Haemato‐oncology subgroup of the British Committee for Standards in Haematology (BCSH) and the British Transplantation Society (BTS) has reviewed the available literature and made recommendations for the diagnosis and management of post‐transplant lymphoproliferative disorder in adult recipients of solid organ transplants. This review details the therapeutic options recommended including reduction in immunosuppression (RIS), transplant organ resection, radiotherapy and chemotherapy. Effective therapy should be instituted before progressive disease results in declining performance status and multi‐organ dysfunction. The goal of treatment should be a durable complete remission with retention of transplanted organ function with minimal toxicity.


Journal of Heart and Lung Transplantation | 2008

The Papworth Experience With the Levitronix CentriMag Ventricular Assist Device

Jeffrey H. Shuhaiber; David P. Jenkins; Marius Berman; Jayan Parameshwar; K. Dhital; Steven Tsui; Stephen R. Large

OBJECTIVES The Levitronix CentriMag ventricular assist device (VAD) is a centrifugal pump designed for short-term extracorporeal support in cardiogenic shock. The aim of this study is to report our clinical experience with the Levitronix CentriMag for uni- and biventricular support. METHODS Between July 2004 and December 2006, 27 patients were supported using the Levitronix CentriMag device. Nineteen were male. Mean age was 47.9 (range 19 to 72) years. Indications for support at implantation were cardiogenic shock that included: end-stage heart failure and too ill to undergo transplantation, with questionable neurologic status (9 subjects); right ventricular failure after left VAD (LVAD) implantation (5 subjects); post-cardiotomy status (7 subjects); and acute donor graft failure after heart transplantation (6 subjects). RESULTS Post-VAD 30-day survival was 30% (8 patients). Mean support time was 11 days for all patients (range 1 to 51 days). Mean support time for 14 Levitronix biventricular VADs was 11 (range 1 to 51) days. Mean support time for 7 Levitronix LVADs was 13.7 (range 1 to 30) days. The highest survival rates after Levitronix support were after donor graft failure (50%) and after cardiotomy (42%). Levitronix right VAD (RVAD) support after long-term LVAD insertion incurred 100% hospital mortality. Of those who survived, 8 patients were discharged home after VAD support and remain alive to date. Two patients were bridged to primary and another bridged to repeat heart transplantation. Five patients were weaned to recovery. Re-operation for bleeding occurred in 8 patients, clinical evidence of cerebral thromboembolism in 3, overwhelming sepsis in 1, and aortic thrombus formation in 1. Clot formation in the tubing was observed in 1 patient, necessitating emergent replacement at bedside, which was successful. CONCLUSIONS The Levitronix CentriMag system is a reliable and facile temporary circulatory support system as a bridge to decision in patients with refractory acute cardiogenic shock.


Thorax | 2003

Atrial septostomy in the treatment of severe pulmonary arterial hypertension

F Reichenberger; J Pepke-Zaba; K McNeil; Jayan Parameshwar; Leonard M. Shapiro

Background: Atrial septostomy (AS) may improve symptoms and haemodynamics in patients with severe pulmonary arterial hypertension (PAH). Methods: Twenty AS performed in 17 patients with severe progressive PAH (13 primary pulmonary hypertension, two collagen vascular disease, one thromboembolic disease, one vaso-occlusive disease) were analysed. Seven patients were in NYHA class III and 10 in NYHA IV. Fifteen patients were on long term prostanoid treatment. AS was performed under fluoroscopy using graded balloon technique. Results: AS improved clinical symptoms and increased the cardiac index from 1.8 to 2.2 l/min/m2 and systemic oxygen transport from 263.2 to 329.6 ml/min/m2 (p<0.001). Procedure related complications included one non-fatal atrial puncture and one unsuccessful septal puncture. Four patients died within 1 week of surgery from uncontrolled tachyarrhythmia (n=1), severe hypoxaemia (n=1), and multiorgan failure (n=2). One further patient died after voluntarily discontinuing renal dialysis. Twelve patients are alive 5–17 months after the operation with five patients undergoing heart-lung transplantation. There were no differences in haemodynamic and functional parameters between the non-survivors and the mid term survivors. However, the non-survivors were significantly older (52 v 36 years, p<0.01) and had a significantly lower creatinine clearance rate (70 ml/min v 48 ml/min, p<0.05). Conclusion: Atrial septostomy improves clinical symptoms, cardiac index, and systemic oxygen transport and has the potential to influence the prognosis in selected cases of severe PAH.


Transplantation | 2003

Diagnostic accuracy of coronary angiography and risk factors for post–heart-transplant cardiac allograft vasculopathy

Linda Sharples; Christopher H. Jackson; Jayan Parameshwar; John Wallwork; Stephen R. Large

Cardiac allograft vasculopathy (CAV) is a common cause of death after heart transplantation. Coronary angiography is used to monitor the progress of recipients. Diagnostic accuracy of angiography and risk factors for CAV have not been clearly established. Between August 1979 and January 2002, 566 1-year survivors of heart transplantation underwent 2,168 angiograms and were classified as having no CAV (0% stenosis), mild-moderate CAV (up to 70% stenosis), or severe CAV (>70% stenosis). We used serial measurements of stenosis to estimate the diagnostic accuracy of angiography and to assess the following risk factors for CAV onset, progression, and survival: recipient and donor age and sex, preoperative ischemic heart disease (IHD), acute rejection rates, cytomegalovirus (CMV) infection, and serologic status. CAV was diagnosed by angiography in 248 of 556 (45%) 1-year survivors, with a mean onset time of 8.6 years. Patients spent a mean of 3.4 years with mild-moderate disease and 3.4 years with severe disease before death. Angiography specificity was 97.8%, and sensitivity was 79.3%. The following variables were found to significantly increase the risk of CAV onset: recipient age relative rate (95% confidence interval) 1.16 (1.01–1.34), donor age by 1.27 (1.13–1.43), male recipient by 2.00 (1.11–2.57), pretransplant IHD by 1.75 (1.30–2.36), cumulative rejection by 1.13 (1.05–1.21), and CMV infection by 1.42 (1.06–1.92). Acute rejection increased risk of death by 1.48 (1.19–1.85). Angiography is highly specific and moderately sensitive for diagnosis of CAV. Risk of CAV onset is related to donor age and recipient history of pretransplant IHD and is further increased by immune-related insults of acute rejection and CMV infection.


Heart | 2011

UK guidelines for referral and assessment of adults for heart transplantation

N.R. Banner; Robert S. Bonser; Andrew L. Clark; Stephen Clark; Peter J. Cowburn; Roy S. Gardner; Paul R Kalra; Theresa A. McDonagh; Chris A. Rogers; Lorna Swan; Jayan Parameshwar; H.L. Thomas; Simon G Williams

Patients with advanced heart failure have a dismal prognosis and poor quality of life. Heart transplantation provides an effective treatment for a subset of these patients. This article provides cardiologists with up-to-date information about referral for transplantation, the role of left ventricular assist devices prior to transplant, patient selection, waiting-list management and donor heart availability. Timing is of central importance; patients should be referred before complications (eg, cardiorenal syndrome or secondary pulmonary hypertension) have developed that will increase the risk of, or potentially contraindicate, transplantation. Issues related to heart failure aetiology, comorbidity and adherence to medical treatment are reviewed. Finally, the positive role that cardiologists can play in promoting and facilitating organ donation is discussed.


Thorax | 2005

Bosentan in inoperable chronic thromboembolic pulmonary hypertension.

Rodney Hughes; P George; Jayan Parameshwar; F Cafferty; John Dunning; N W Morrell; Joanna Pepke-Zaba

Chronic thromboembolic pulmonary hypertension (CTEPH) is a devastating disease in which the pulmonary vasculature becomes obstructed by organised fibrotic material, presumed to be the consequence of incomplete resolution of pulmonary emboli. The ensuing increased pulmonary vascular resistance and right ventricular dysfunction results in severe exercise limitation, symptomatic right heart failure, and markedly impaired survival. Recent studies suggest that the frequency of this condition is higher than previously appreciated, occurring in up 3.8% of patients following acute pulmonary embolism after 2 years.1 The treatment of choice is pulmonary endarterectomy (PEA), a potentially curative surgical procedure in which the fibrotic material is removed from …


Journal of Heart and Lung Transplantation | 2002

The incidence of end-stage renal failure in 17 years of heart transplantation: a single center experience

Duwarakan K. Satchithananda; Jayan Parameshwar; Linda Sharples; Gordon Taylor; Keith McNeil; John Wallwork; Stephen R. Large

BACKGROUND Predictions of the incidence of renal failure within a heart transplant population are based on the early experiences of cyclosporine (CsA)-based immunosuppression. We report a single-center experience of end-stage renal failure (ESRF) during a 17-year period encompassing current lower dose CsA regimens. METHOD Prospectively collected data were analyzed on all patients who underwent first heart transplants between April 1982 and February 1999 (n = 697). We further categorized patients by the date of transplantation into a higher and lower dosage maintenance CsA group. RESULTS End-stage renal failure developed in 44 patients. The median time to dialysis was 87 months after transplantation and was independent of the initial CsA regimens used (p = 0.798). In the ESRF group, 14 underwent hemodialysis, 28 underwent peritoneal dialysis, and 9 underwent renal transplantation. One- and 5-year survival rates after dialysis were 82% and 62% respectively. The incidence of ESRF at our institution was 5.8%. It increased with post-operative survival and was independent of the initial CsA regimen used. We found no difference in pre-transplant age, sex, diagnosis, immediate post-operative creatinine, or the development of diabetes between the ESRF group and controls. The ESRF group received higher dosages of CsA within the first post-transplant year, although this did not reach significance (CsA dosage, 5.9 microg/kg/day vs 5.1 microg/kg/day, respectively p = 0.075). CONCLUSIONS Lower dosage CsA regimes have not altered the incidence of ESRF at our institution, suggesting an individual predisposition to nephropathy. Therefore, reduction in the future incidence of ESRF may rely on extremely low-dose or calcineurin-free immunosuppression regimes.


Therapeutic Drug Monitoring | 1999

Randomized, trough blood cyclosporine concentration-controlled trial to compare the pharmacodynamics of Sandimmune and Neoral in de novo lung transplant recipients

Andrew K. Trull; Louise Steel; Linda Sharples; Susan Stewart; Jayan Parameshwar; Keith McNeil; John Wallwork

The greater and more consistent absorption of cyclosporine from the microemulsion formulation (Neoral; Novartis Pharmaceuticals Ltd., Frimley, UK) when compared with that from the original form (Sandimmune; Novartis Pharmaceuticals Ltd., Frimley, UK) results in greater systemic exposure. Lung transplant recipients could particularly benefit from this enhanced exposure, but not at the expense of excessive cyclosporine toxicity. We compared the pharmacodynamics of Neoral and Sandimmune over the first postoperative year in 50 lung transplant recipients. Twenty-eight patients were randomly selected to receive Neoral and 22 to receive Sandimmune. Nine patients with cystic fibrosis (CF) were randomly selected independently (5, Neoral; 4, Sandimmune). Patients were maintained on similar trough blood cyclosporine concentrations (C0) throughout the 12-month follow-up. A limited blood sampling strategy was adopted to compare the pharmacokinetics of the two formulations at the end of weeks 1 to 4, and of weeks 13, 26, 39, 52. The influence of any difference between the pharmacokinetics of Neoral and Sandimmune on either efficacy or toxicity of the drug was investigated during the follow-up period. Patients in the Neoral and the Sandimmune groups were matched demographically. There were no differences in dose-normalized blood cyclosporine concentrations measured predose (C0) or 6 hours postdose between the two groups. However, the measurement at 2 hours postdose (C2) and the total AUC0-6 were significantly greater in the Neoral group in both CF and non-CF patients at all visits (p < 0.001). Non-CF patients required 9% lower doses of Neoral to achieve comparable C0 measurements to those patients receiving Sandimmune. However, patients with CF required 2 to 3 times the dose of both Neoral and Sandimmune to achieve the same C0 as non-CF patients. The linear rejection rate in the Sandimmune group was 1.87 episodes per patient year, which was similar to the rejection rate of 1.97 episodes per patient year in the Neoral group. Serial lung function, blood biochemistry and hematology, mortality and the incidence of severe renal dysfunction, hypertension, infection, seizures, and new-onset diabetes were all similar in the two groups. Despite equivalent C0, those in the Neoral group were consistently exposed to greater blood cyclosporine concentrations during the dosing interval than those in the Sandimmune group. This did not increase the incidence of serious cyclosporine-associated side effects or influence the rate of acute rejection either. When data from the Neoral and Sandimmune groups were combined, measurements of C0 but not C2 or C6 were associated with the risk of acute lung allograft rejection.

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