Nadeem Anwar - Academia.edu (original) (raw)

Papers by Nadeem Anwar

Radiology, 2022

Background Portal hypertension in the Fontan circulation is a function of elevated systemic venou... more Background Portal hypertension in the Fontan circulation is a function of elevated systemic venous pressure and liver fibrosis. Purpose To quantify the prevalence of radiologic evidence of portal hypertension and elevated VAST score (one point each for varices, ascites, splenomegaly, and thrombocytopenia) of 2 or greater in children and adults with Fontan circulation and to determine the association with hemodynamics and adverse outcomes. Materials and Methods This was a retrospective study of individuals with Fontan circulation who underwent abdominal MRI or CT for focal liver lesion surveillance between January 2012 and December 2019. Portal hypertension was defined as the presence of at least two of the following: varices, ascites, or splenomegaly. Fontan deterioration was defined as a composite of heart failure signs or symptoms requiring diuretic escalation, placement of a ventricular assist device, heart transplant, or death. Relationships between variables and the composite end point were assessed using univariable and multivariable logistic regression. Results A total of 123 patients (age range, 9-55 years; 32 children) were evaluated (median age, 23 years; IQR, 17-30 years; 63 male patients). Median time since diagnosis of Fontan circulation was 16 years (IQR, 12-23 years). Twenty-five of the 123 patients (20%) had radiologic evidence of portal hypertension, and 34 (28%) had a VAST score of 2 or greater. Fontan deterioration occurred in 25 of the 123 patients (20%); median follow-up duration was 0.4 year (IQR, 0.1-3.1 years). Compared with patients who had Fontan circulation without deterioration, patients with Fontan deterioration were more likely to have moderate or severe ventricular systolic dysfunction (P < .01), moderate or severe atrioventricular valve regurgitation (P < .01), higher Fontan pressure (P = .01), radiologic evidence of portal hypertension (P < .01), and VAST score of 2 or greater (P < .01). Conclusion Radiologic evidence of portal hypertension at abdominal imaging in children and adults with Fontan circulation was associated with higher venous pressures and an increased risk for Fontan deterioration. These characteristics may be used to identify patients who warrant comprehensive hemodynamic evaluation. © RSNA, 2022.

Cardiology in the Young, 2021

Patients with single-ventricle CHD undergo a series of palliative surgeries that culminate in the... more Patients with single-ventricle CHD undergo a series of palliative surgeries that culminate in the Fontan procedure. While the Fontan procedure allows most patients to survive to adulthood, the Fontan circulation can eventually lead to multiple cardiac complications and multi-organ dysfunction. Care for adolescents and adults with a Fontan circulation has begun to transition from a primarily cardiac-focused model to care models, which are designed to monitor multiple organ systems, and using clues from this screening, identify patients who are at risk for adverse outcomes. The complexity of care required for these patients led our centre to develop a multidisciplinary Fontan Management Programme with the primary goals of earlier detection and treatment of complications through the development of a cohesive network of diverse medical subspecialists with Fontan expertise.

The American Journal of Cardiology, 2021

Elevated central venous pressure in those with Fontan circulation causes liver congestion and hep... more Elevated central venous pressure in those with Fontan circulation causes liver congestion and hepatomegaly. We assessed if liver volume by magnetic resonance imaging (MRI) is associated with adverse cardiovascular outcomes. Retrospective study of 122 patients with Fontan circulation who were >10 years old and had a liver MRI with magnetic resonance elastography. Liver volume (ml) was measured by manual segmentation from axial T2-weighted images and was indexed to body surface area. The composite outcome included death, heart transplant, ventricular assist device placement, or nonelective cardiovascular hospitalization. The median age at the time of MRI was 18.9 (interquartile range 15.8 to 25.9) years, and 47% of the patients were women. The mean indexed liver volume was 1,133 ± 180 ml/m2. Indexed liver volume was not significantly associated with age, years since Fontan, or with liver stiffness (r = 0.15, p = 0.10), but was positively correlated with Fontan pressure (r = 0.32, p = 0.002). Over a median follow-up of 2.1 (0.8 to 4.2) years, 32 patients (26%) experienced the composite outcome. Higher indexed liver volume was associated with a greater hazard for the composite outcome (hazard ratio per 1 SD increase = 1.74, 95% confidence interval 1.27 to 2.35, p = 0.0004) but increased liver stiffness was not significantly associated with the composite outcome (hazard ratio per 1 SD increase 1.44, 95% confidence interval 0.90 to 2.21, p = 0.11). In conclusion, greater liver volume indexed to body surface area is associated with unfavorable hemodynamics and adverse outcomes in patients with Fontan circulation. Liver volume may be a useful, simple imaging biomarker in adolescents and adults with Fontan circulation.

Polymer Science, Series B, 2021

All rights, including copyright, in the content of this document are owned or controlled for thes... more All rights, including copyright, in the content of this document are owned or controlled for these purposes by FSTC Limited. In accessing these web pages, you agree that you may only download the content for your own personal non-commercial use. You are not permitted to copy, broadcast, download, store (in any medium), transmit, show or play in public, adapt or change in any way the content of this document for any other purpose whatsoever without the prior written permission of FSTC Limited.

Circulation, 2020

Introduction: Hepatic steatosis is a leading cause of chronic liver disease, and it is most commo... more Introduction: Hepatic steatosis is a leading cause of chronic liver disease, and it is most commonly attributed to nonalcoholic fatty liver disease (NAFLD). The interplay between hepatic steatosis ...

International Journal of Cardiology, 2021

BACKGROUND Fontan-associated liver disease (FALD) is universal in patients with a Fontan circulat... more BACKGROUND Fontan-associated liver disease (FALD) is universal in patients with a Fontan circulation. Hepatocellular carcinoma (HCC) is one of its severe expressions, and, though rare, frequently fatal. The purpose of this study was to describe the clinical presentation, risk factors, and outcomes of HCC in patients with a Fontan circulation. METHODS A multicenter case series of Fontan patients with a diagnosis of HCC formed the basis of this study. The case series was extended by published cases and case reports. Clinical presentation, tumor characteristics, laboratory and hemodynamic findings as well as treatment types and outcomes, were described. RESULTS Fifty-four Fontan patients (50% female) with a diagnosis of HCC were included. Mean age at HCC diagnosis was 30 ± 9.4 years and mean duration from Fontan surgery to HCC diagnosis was 21.6 ± 7.4 years. Median HCC size at the time of diagnosis was 4 cm with a range of 1 to 22 cm. The tumor was located in the right hepatic lobe in 65% of the patients. Fifty-one percent had liver cirrhosis at the time of HCC diagnosis. Fifty percent of the patients had no symptoms related to HCC and alpha-fetoprotein was normal in 26% of the cases. Twenty-six patients (48%) died during a median follow-up duration of 10.6 (range 1-50) months. CONCLUSIONS HCC in Fontan patients occurs at a young age with a 1-year survival rate of only 50%. Meticulous liver surveillance is crucial to detect small tumors in the early stage.

Journal of the American Heart Association, 2021

Background Hypocholesterolemia is a marker of liver disease, and patients with a Fontan circulati... more Background Hypocholesterolemia is a marker of liver disease, and patients with a Fontan circulation may have hypocholesterolemia secondary to Fontan‐associated liver disease or inflammation. We investigated circulating lipids in adults with a Fontan circulation and assessed the associations with clinical characteristics and adverse events. Methods and Results We enrolled 164 outpatients with a Fontan circulation, aged ≥18 years, in the Boston Adult Congenital Heart Disease Biobank and compared them with 81 healthy controls. The outcome was a combined outcome of nonelective cardiovascular hospitalization or death. Participants with a Fontan (median age, 30.3 [interquartile range, 22.8–34.3 years], 42% women) had lower total cholesterol (149.0±30.1 mg/dL versus 190.8±41.4 mg/dL, P <0.0001), low‐density lipoprotein cholesterol (82.5±25.4 mg/dL versus 102.0±34.7 mg/dL, P <0.0001), and high‐density lipoprotein cholesterol (42.8±12.2 mg/dL versus 64.1±16.9 mg/dL, P <0.0001) than ...

Polymer Science, Series A, 2020

The main purpose of this research work is to synthesize polypyrrole (PPy) and polypyrrole (PPy)-c... more The main purpose of this research work is to synthesize polypyrrole (PPy) and polypyrrole (PPy)-cadmium oxide (CdO) nanocomposites with different concentrations by using in-situ chemical polymerization method. Thin films of the synthesized composites were prepared by doctor blade method. The samples were characterized by XRD technique and four probe method to find the structure and electrical conductivity of the prepared (PPy-CdO) nanocomposites. The XRD of PPy shows amorphous nature due to single broad peak. XRD of pure CdO shows crystalline nature due to sharp peaks. In the XRD of (PPy-CdO) nanocomposites, sharp peaks are obtained which shows the crystalline nature of composites. As the concentration of CdO is increasing, the sharp peaks shift towards lower angles and d-spacing is increasing that may attribute to increase in crystallite size of nanocomposites. The DC electrical conductivity of nanocomposites was calculated by four- probe method at room temperature. Results reveal that by increasing the concentration of CdO in PPy, the conductivity of the nanocomposite is also increasing. Schottky diode characteristics were taken by two probe method. From the obtained I–V curves, it was concluded that only space charge limited current (SCLC) holds in our case at higher voltages which is suitable for Schottky diode applications.

Journal of Materials Science: Materials in Electronics, 2020

Polypyrrole (PPy) conducting polymer was prepared via oxidative polymerization of pyrrole monomer... more Polypyrrole (PPy) conducting polymer was prepared via oxidative polymerization of pyrrole monomers and the existence of oxidant such as ammonium persulphate (APS). Subsequently, similar method was adopted to get doped polypyrrole and its PPy-DBSA-Y2O3 composites. The phase of the prepared materials was elucidated using X-ray diffraction. The SEM/EDX analysis confirmed the dual phase structure of platelet and flakier shape in PPy-DBSA-Y2O3 composite and the presence of yttrium oxide. The UV–Vis as well as photoluminescence band show various electronic levels present in PPy-DBSA-Y2O3 composites. Synthesis of PPy-DBSA-Y2O3 composite with a large real dielectric modulus and lower optical band gap is appropriate semiconductor material for optoelectronic devices applications.

Gastroenterology, 2019

Background:: The need for accurate noninvasive biomarkers of fibrotic progression is important fo... more Background:: The need for accurate noninvasive biomarkers of fibrotic progression is important for HCV treatment decisions and ongoing management of HIV/HCV coinfected subjects. The Enhanced Liver Fibrosis (ELF)-index is a mathematical algorithm calculated by combining three serum markers: hyaluronic acid (HA), amino-terminal pro-peptide of type III procollagen (PIIINP), and tissue inhibitor of metalloproteinase 1 (TIMP-1). We compared the performance of ELF-index to FIB4 and APRI at different liver fibrosis stages. We sought to validate the tests efficacy of the three non-invasive biomarkers as compared to liver histology in HIV/HCV co-infected patients. Methods: In this study, we evaluated the ELFindex, FIB4, and APRI scores in a cohort of HIV/HCV coinfected patients, and validated its results against known histological METAVIR scoring in the same patients. All patients were enrolled in the University of Cincinnati repository collection or observational and treatment trials that provided permission for serum/tissue collection and use. Demographics and recorded clinical laboratory data were used for comparison. ELF-index levels were quantified using commercial ELISA assays. Analysis of variance and area under the receiver-operating curve (AUROC) were measured in GraphPad and MedCalc software. Results: Eighty HIV/ HCV coinfected patient samples were evaluated. The ELF-index increased with histological stage of liver fibrosis showing significant differences between groups (p < 0.0001). A significant correlation between ELF-index and METAVIR fibrosis score was observed (r = 0.8018, p < 0.0001, 95% CI 0.70-0.87). The performance of the ELF-index was evaluated by area under the curve analysis and showed excellent prediction of severe liver fibrosis (≥F3) (AUROC= 0.99; 95%CI 0.97 to 1.00) and cirrhosis (F4) (AUROC= 0.96; 95% CI =0.92 to 1.00) but slightly lower performance for significant liver fibrosis (≥F2) (AUROC= 0.88; 95%CI 0.81 to 0.96). Pairwise comparison of ROC curves showed better performance of ELF-index than FIB4 and APRI at any fibrosis ≥F1 (AUROC= 0.898, 0.596,p=ns and 0.549,p= ns), Significant fibrosis ≥F2 (AUROC= 0.845, 0.735,p=ns and 0.633, p<0.0121), severe fibrosis ≥F3 (AUROC= 0.959, 0.677, p<0.0001 and 0.502, p<0.0001), and cirrhosis F4 (AUROC= 1.00, 0.82,p=0.0059 and 0.727, p=0007). Conclusion: The performance of the ELF-index, FIB4 and APRI tests were assessed in a cohort of HIV/HCV coinfected patients and demonstrated excellent characteristics towards accurate prediction of liver fibrosis and cirrhosis when compared to liver biopsy METAVIR scores. ELF-index displayed superior performance to FIB4 and APRI in this cohort of patients. Applying this simple noninvasive blood test for liver fibrosis screening is warranted. This work is supported by R56AI065256 to KES from the NIH NIAID.

American Journal of Gastroenterology, 2017

American Journal of Gastroenterology, 2005

The American Journal of Cardiology, 2019

Fontan associated liver disease is associated with morbidity and mortality in palliated single-ve... more Fontan associated liver disease is associated with morbidity and mortality in palliated single-ventricle congenital heart disease patients. Magnetic resonance elastography (MRE) provides a quantitative assessment of liver stiffness in Fontan patients. We hypothesized that MRE liver stiffness correlates with liver enzymes, hemodynamics, portal hypertension, and Fontan failure (FF). All adult Fontan patients who had MRE between 2011 and 2018 were included. Radiologic portal hypertension was defined as splenomegaly, ascites, and/or varices. FF was defined as death, transplantation, or heart failure symptoms requiring escalation of diuretics. Seventy patients with a median age of 24.7 years and a median follow-up from MRE of 3.9 years were included. The median liver stiffness was 4.3 kPa (interquartile range [IQR]: 3.8 to 5.0 kPa). There was a weak, positive correlation between liver stiffness and Fontan pathway pressure (r = 0.34, p = 0.03). There was a moderate negative correlation of liver stiffness with ventricular ejection fraction (r = À0.52, p = 0.03). Liver stiffness was weakly positively correlated with liver transaminases and gamma glutamyl transferase. Patients with portal hypertension had higher liver stiffness compared to patients without (5.2 § 1.3 vs 4.2 § 0.8 kPa, p = 0.03). At MRE or during follow-up, 13 patients (19%) met definition of FF and had significantly higher liver stiffness compared to patients without FF (5.1 [IQR: 4.3 to 6.3] vs 4.2 [IQR: 3.7 to 4.7] kPa, p = 0.01). Liver stiffness above 4.5 kPa differentiated FF with a sensitivity of 77% and specificity of 77%. In conclusion, elevated MRE-derived liver stiffness is associated with worse hemodynamics, liver enzymes and clinical outcomes in Fontan patients. This measure may serve as a global imaging biomarker of Fontan health.

Liver Transplantation, 2019

The use of donation after circulatory death (DCD) liver allografts has been constrained by limita... more The use of donation after circulatory death (DCD) liver allografts has been constrained by limitations in the duration of donor warm ischemia time (DWIT), donor agonal time (DAT), and cold ischemia time (CIT). The purpose of this study is to assess the impact of longer DWIT, DAT, and CIT on graft survival and other outcomes in DCD liver transplants. The Scientific Registry of Transplant Recipients was queried for adult liver transplants from DCD donors between 2009 and 2015. Donor, recipient, and center variables were included in the analysis. During the study period, 2107 patients underwent liver transplant with DCD allografts. In most patients, DWIT and DAT were <30 minutes. DWIT was <30 minutes in 1804 donors, between 30 and 40 minutes in 248, and >40 minutes in 37. There was no difference in graft survival, duration of posttransplant hospital length of stay, and readmission rate between DCD liver transplants from donors with DWIT <30 minutes and DWIT between 30 and 40 minutes. Similar outcomes were noted for DAT. In the multivariate analysis, DAT and DWIT were not associated with graft loss. The predictors associated with graft loss were donor age, donor sharing, CIT, recipient admission to the intensive care unit, recipient ventilator dependence, Model for End-Stage Liver Disease score, and low-volume transplant centers. Any CIT cutoff >4 hours was associated with increased risk for graft loss. Longer CIT was also associated with a longer posttransplant hospital stay, higher rate of primary nonfunction, and hyperbilirubinemia. In conclusion, slightly longer DAT and DWIT (up to 40 minutes) were not associated with graft loss, longer posttransplant hospitalization, or hospital readmissions, whereas longer CIT was associated with worse outcomes after DCD liver transplants.

American Journal of Gastroenterology, 2007

Journal of the American College of Surgeons, 2018

BACKGROUND Given the shortage of available liver grafts, transplantation (LTx) of hepatitis C vir... more BACKGROUND Given the shortage of available liver grafts, transplantation (LTx) of hepatitis C virus antibody-positive, nucleic acid test-negative (HCV Ab+/NAT-) livers into nonviremic HCV recipients can expand the donor pool. Having previously described the sentinel experience of HCV Ab+/NAT- allografts in nonviremic recipients, we report the growth and extended follow-up of this program for 55 patients compared with recipients of Public Health Services (PHS) increased-risk donor HCV Ab-/NAT- allografts. STUDY DESIGN A prospective review of all HCV nonviremic LTx patients receiving HCV Ab+/NAT- organs between March 2016 and August 2018 was performed. All HCV Ab+/NAT- organ recipients underwent HCV testing at 3 months and 1-year post-LTx to determine HCV transmission. RESULTS Fifty-five HCV nonviremic candidates received HCV Ab+/NAT- organs; 64% male, median age 59 years (range 36 to 69 years) and median Model for End-Stage Liver Disease score of 22.5. Two recipients were excluded due to death before HCV testing. The HCV disease transmission occurred in 5 recipients (9%). Of these, 4 (80%) underwent anti-HCV treatment with eradication of virus. No patient found to be negative at 3 months seroconverted at 1-year follow-up. No patients who received PHS increased-risk donor HCV Ab-/NAT- organs had viremia develop (0 of 57) and there was no difference in graft and renal function, complications, or survival between HCV Ab+/NAT- recipients and PHS increased-risk donor HCV Ab-/NAT- recipients. CONCLUSIONS We report the largest experience with LTx from HCV Ab+/NAT- donors into 55 seronegative recipients with a HCV transmission rate of 9% with no late conversions at 1 year and no difference in function or graft loss compared with PHS increased-risk donor HCV Ab-/NAT- recipients. Due to availability of safe and effective HCV therapies, the use of such organs should be strongly considered to increase the donor organ pool.

Journal of Clinical Oncology, 2013

237 Background: Sorafenib plays a role in the treatment of advanced HCC; however its role after L... more 237 Background: Sorafenib plays a role in the treatment of advanced HCC; however its role after Ltx has not yet been defined in the adjuvant setting. Patients at high risk for HCC recurrence, or those with recurrence after Ltx may benefit from this therapy. Methods: We present our institution’s experience of the use of sorafenib in the post Ltx setting in 11 patients. High risk for HCC recurrence (9 patients) was defined as vascular invasion, lymphovascular invasion, liver capsule invasion, or >3 tumors present in the liver explant. 2 patients had recurrent HCC post Ltx. The starting dose of sorafenib varied, but was most commonly 200mg po BID. Patients were seen monthly while on sorafenib, and 4-phase liver CTs or MRIs were performed every 3 months. Results: Median age at Ltx was 55 (range 48-77). Median time between Ltx and start of sorafenib was 150 days (range 30-543). Reasons for sorafenib use were high risk of recurrence 8/11 (72.7%), recurrence 2/11 (18.2%), rising AFP 1/1...

Journal of the American College of Cardiology, 2017

European Respiratory Journal, Sep 1, 2011

Background: British Thoracic Society (BTS) guidelines on Emergency Oxygen (O2) in 2008 highlighte... more Background: British Thoracic Society (BTS) guidelines on Emergency Oxygen (O2) in 2008 highlighted the importance of safe prescription and administration of O2. We audited our practice focussing on the documentation, prescription and complications in a busy district general hospital in UK. Methods: Audit was performed on patients admitted to the medical admission unit over a period of 3 months between Jan 2010 to Mar 2010. Patients who had O2 were randomly selected and monitored from admission to discharge. Results: 56 patients in total were studied. 46% had assessment for the risk of Co2 retention before O2 started. Only 34% had documentation of target O2 saturations. Documentation of Device in 66%, Flow in 71% and Fio2 in 32% of cases. 96% of drug charts had no prescription of O2. There is no documentation how long O2 should be given in all the cases. 20 (36%) patients had inappropriate administration of O2; No need for O2-10, More O2 than needed-9 and Less O2 than needed-1. 3 patients developed Type 2 respiratory failure and needed Non-invasive ventilation. There were no mortalities. Conclusions: We identified safety issues whilst administering Emergency O2 and need to improve in our documentation, prescription on drug charts and administration. Patients at risk of Co2 retention would have arterial blood samples after starting O2. Drug charts were modified adding oxygen in 2 areas: Regular and PRN sections and also include device, flow, Fio2, target saturations and how long to give O2. Flow charts on how to administer and adjust O2 were placed in all the wards including medical admission units. Repeated mandatory educational training on O2 administration to all medical, nursing and allied health care professionals were started.