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Featured researches published by George Therapondos.


Hepatology | 2009

Randomized controlled trial of carvedilol versus variceal band ligation for the prevention of the first variceal bleed

Dhiraj Tripathi; James Ferguson; Narendra Kochar; Joanna A. Leithead; George Therapondos; Norma C. McAvoy; Adrian J. Stanley; Ewan H. Forrest; William S. Hislop; Peter R. Mills; Peter C. Hayes

Current therapy for preventing the first variceal bleed includes beta‐blocker and variceal band ligation (VBL). VBL has lower bleeding rates, with no differences in survival, whereas beta‐blocker therapy can be limited by side effects. Carvedilol, a non‐cardioselective vasodilating beta‐blocker, is more effective in reducing portal pressure than propranolol; however, there have been no clinical studies assessing the efficacy of carvedilol in primary prophylaxis. The goal of this study was to compare carvedilol and VBL for the prevention of the first variceal bleed in a randomized controlled multicenter trial. One hundred fifty‐two cirrhotic patients from five different centers with grade II or larger esophageal varices were randomized to either carvedilol 12.5 mg once daily or VBL performed every 2 weeks until eradication using a multibander device. Seventy‐seven patients were randomized to carvedilol and 75 to VBL. Baseline characteristics did not differ between the groups (alcoholic liver disease, 73%; median Child‐Pugh score, 8; median age, 54 years; median follow‐up, 20 months). On intention‐to‐treat analysis, carvedilol had lower rates of the first variceal bleed (10% versus 23%; relative hazard 0.41; 95% confidence interval 0.19‐0.96 [P = 0.04]), with no significant differences in overall mortality (35% versus 37%, P = 0.71), and bleeding‐related mortality (3% versus 1%, P = 0.26). Six patients in the VBL group bled as a result of banding ulcers. Per‐protocol analysis revealed no significant differences in the outcomes. Conclusion: Carvedilol is effective in preventing the first variceal bleed. Carvedilol is an option for primary prophylaxis in patients with high‐risk esophageal varices. (HEPATOLOGY 2009.)


Gut | 2002

The role of the transjugular intrahepatic portosystemic stent shunt (TIPSS) in the management of bleeding gastric varices: clinical and haemodynamic correlations

Dhiraj Tripathi; George Therapondos; E Jackson; Doris N. Redhead; P.C. Hayes

Background: The transjugular intrahepatic portosystemic stent shunt (TIPSS) is effective in the management of both oesophageal and gastric variceal bleeding. Although it has been reported that gastric varices can bleed at pressures of ≤12 mm Hg, this phenomenon has been little studied in the clinical setting. Aims: To assess the efficacy of TIPSS on rebleeding and mortality following gastric and oesophageal variceal bleeding, and the importance of portal pressure in both groups. Methods: Forty eligible patients who had bled from gastric varices and 232 from oesophageal varices were studied. Patients were also subdivided into those whose portal pressure gradients (PPG) prior to TIPSS were ≤12 mm Hg (group 1) and >12 mm Hg (group 2). Results: There was no difference in Child-Pugh score, age, sex, or alcohol related disease between patients bleeding from gastric or oesophageal varices. Patients who bled from gastric varices had a lower PPG pre-TIPSS (15.8 (0.8) v 21.44 (0.4) mm Hg; p<0.001). There was no difference in the rebleeding rate (20.0% v 14.7%; NS). There was a significant difference (p<0.05) in favour of the gastric varices group in the one year mortality (30.7% v 38.7%) and five year mortality (49.5% v 74.9%), particularly in those patients in group 2. Gastric variceal bleeding accounted for significantly more cases in group 1 than in group 2 (36.8% v 10.2%; p<0.001). Most patients in group 2 who rebled had a PPG post-TIPSS of >7 mm Hg. Conclusions: TIPSS is equally effective in the prevention of rebleeding following gastric and oesophageal variceal bleeding. A significant proportion of gastric varices bleed at a PPG ≤12 mm Hg. The improved mortality in patients with gastric variceal bleeding is seen only in those that bleed at a PPG >12 mm Hg, and warrants further study.


Transplantation | 2009

Antiviral treatment of recurrent hepatitis C after liver transplantation: predictors of response and long-term outcome.

Nazia Selzner; Eberhard L. Renner; Markus Selzner; Oyedele Adeyi; Arash Kashfi; George Therapondos; Nigel Girgrah; Chaturika Herath; Gary A. Levy; Leslie B. Lilly

Background. Efficacy and long-term outcome of antiviral therapy for recurrent hepatitis C after liver transplantation is poorly defined. Aim. This study aimed at assessing the efficacy of antiviral therapy regarding sustained hepatitis C virus (HCV) clearance, liver histology, and patient survival. Methods. We retrospectively reviewed all 446 patients who received a liver allograft at our institution for HCV-related cirrhosis between January 1992 and December 2006. Two hundred thirty-two patients (52%) were eligible for antiviral therapy based on predefined criteria (Metavir stage ≥1 and/or grade ≥2; protocol biopsies). One hundred seventy-two patients (39%) had no contraindication for treatment, received more than or equal to 1 dose of interferon-&agr;–based combination therapy, and form the basis of this analysis. Therapy was aimed for 48 weeks; median posttreatment follow-up was 68 months. Results. The overall sustained virological response (SVR) rate was 50% (genotype 1/4: 40%; genotype 2/3: 76%). SVR was higher on cyclosporine A (CsA) (56%) than on tacrolimus (44%, P=0.05), largely because of a lower relapse rate (6% vs. 19%, P=0.01). In multivariate analysis, genotype 2/3, CsA use, donor age, and pretreatment necroinflammatory activity were independently associated with SVR. SVR significantly improved histology and long-term survival (actuarial 5-year survival 96% vs. 69% in nonresponders, P<0.0001). Conclusion. Antiviral therapy of recurrent hepatitis C after liver transplantation is able to clear HCV in half the patients, more likely on CsA than on tacrolimus, and markedly improves outcome.


Transplantation | 2000

The effect of polymorphisms in tumor necrosis factor-alpha, interleukin-10, and transforming growth factor-beta1 genes in acute hepatic allograft rejection.

Andrew J. Bathgate; Vera Pravica; Chris Perrey; George Therapondos; John Plevris; Peter C. Hayes; Ian V. Hutchinson

BACKGROUND The occurrence of acute rejection in orthotopic liver transplantation is unpredictable. The role of cytokines in the process of rejection is not entirely clear. We investigated polymorphisms in the genes encoding tumor necrosis factor (TNF)-alpha, interleukin (IL)-10, and transforming growth factor (TGF)-beta1, which affect the amount of cytokine produced in vitro, in a liver transplant population to determine any association with acute rejection. METHOD DNA was extracted from whole blood of liver transplant patients. After amplification with polymerase chain reactions, the polymorphisms at TNF-alpha -308, IL-10 -1082, and TGF-beta1 +869 and +915 were determined using sequence-specific oligonucleotide probes. Acute cellular rejection was a clinical and histological diagnosis. RESULTS Acute cellular rejection requiring treatment occurred in 68 (48%) of 144 patients. Acute cellular rejection was significantly associated with the TNF-alpha -308 A/A genotype (P<0.02). There was no significant association with either IL-10 or TGF-beta1 polymorphisms in acute rejection. CONCLUSION Patients with a homozygous TNF-alpha -308 genotype A/A are more likely to suffer from acute cellular rejection after liver transplantation.


The American Journal of Gastroenterology | 2002

Endoscopic use of human thrombin in bleeding gastric varices.

Wei Lyn Yang; Dhiraj Tripathi; George Therapondos; Audrey Todd; Peter C. Hayes

OBJECTIVE:The management of gastric variceal hemorrhage remains a clinical challenge. Bovine thrombin has been reported to be effective in two small series. We report our experience with human thrombin in the treatment of bleeding gastric varices.METHODS:We reviewed the case records of 12 patients presenting over a 2-yr period with gastric variceal bleeding requiring endoscopic injection of human thrombin. Ten were male and the mean age was 52 yr (range = 26–83). The underlying diagnoses were cirrhosis in nine, portal vein thrombosis in two, and liver metastasis in one. The majority had fundal gastric varices, and none were thought to have bled from their esophageal varices. Eight received thrombin as primary treatment, whereas four had thrombin only after failing transjugular intrahepatic portosystemic shunts. Patients received one to four sessions (mean = 1.9) of thrombin with a mean total dose of 1833 U (range = 800–4000). Mean follow-up was 17.8 months for those still alive (range = 7–33).RESULTS:Hemostasis in the acute setting was successful in nine patients all of whom received thrombin within 48 hours of the bleed. In the longer term, nine of the 12 had no further bleeding. Of these, five patients did well with thrombin alone, one died of cancer, and the other three went on electively to more definitive shunt procedures. Three patients rebled from their gastric varices of which one was successfully retreated with thrombin. Only one death was related to variceal bleeding (8%). No adverse reactions were noted.CONCLUSION:Our experience demonstrates that endoscopic therapy with thrombin appears safe and can be effective in the management of gastric variceal bleeding.


American Journal of Transplantation | 2010

Adult living liver donors have excellent long-term medical outcomes: the University of Toronto liver transplant experience.

Lesley Adcock; C. Macleod; Derek DuBay; Paul D. Greig; Mark S. Cattral; Ian D. McGilvray; Les Lilly; Nigel Girgrah; Eberhard L. Renner; Markus Selzner; Nazia Selzner; A. Kashfi; R. Smith; S. Holtzman; Susan E. Abbey; David R. Grant; Gary A. Levy; George Therapondos

Right lobe living donor liver transplantation is an effective treatment for selected individuals with end‐stage liver disease. Although 1 year donor morbidity and mortality have been reported, little is known about outcomes beyond 1 year. Our objective was to analyze the outcomes of the first 202 consecutive donors performed at our center with a minimum follow‐up of 12 months (range 12–96 months). All physical complications were prospectively recorded and categorized according to the modified Clavien classification system. Donors were seen by a dedicated family physician at 2 weeks, 1, 3 and 12 months postoperatively and yearly thereafter. The cohort included 108 males and 94 females (mean age 37.3 ± 11.5 years). Donor survival was 100%. A total of 39.6% of donors experienced a medical complication during the first year after surgery (21 Grade 1, 27 Grade 2, 32 Grade 3). After 1 year, three donors experienced a medical complication (1 Grade 1, 1 Grade 2, 1 Grade 3). All donors returned to predonation employment or studies although four donors (2%) experienced a psychiatric complication. This prospective study suggests that living liver donation can be performed safely without any serious late medical complications and suggests that long‐term follow‐up may contribute to favorable donor outcomes.


American Journal of Transplantation | 2009

Adult Right-Lobe Living Liver Donors: Quality of Life, Attitudes and Predictors of Donor Outcomes

Derek DuBay; S. Holtzman; Lesley Adcock; Susan E. Abbey; S. Greenwood; C. Macleod; A. Kashfi; M. Jacob; Eberhard L. Renner; David R. Grant; Gary A. Levy; George Therapondos

To refine selection criteria for adult living liver donors and improve donor quality of care, risk factors for poor postdonation health‐related quality of life (HRQOL) must be identified. This cross‐sectional study examined donors who underwent a right hepatectomy at the University of Toronto between 2000 and 2007 (n = 143), and investigated predictors of (1) physical and mental health postdonation, as well as (2) willingness to participate in the donor process again. Participants completed a standardized HRQOL measure (SF‐36) and measures of the pre‐ and postdonation process. Donor scores on the SF‐36 physical and mental health indices were equivalent to, or greater than, population norms. Greater predonation concerns, a psychiatric diagnosis and a graduate degree were associated with lower mental health postdonation whereas older donors reported better mental health. The majority of donors (80%) stated they would donate again but those who perceived that their recipient engaged in risky health behaviors were more hesitant. Prospective donors with risk factors for lower postdonation satisfaction and mental health may require more extensive predonation counseling and postdonation psychosocial follow‐up. Risk factors identified in this study should be prospectively evaluated in future research.


Liver Transplantation | 2008

The Difference in the Fibrosis Progression of Recurrent Hepatitis C After Live Donor Liver Transplantation Versus Deceased Donor Liver Transplantation Is Attributable to the Difference in Donor Age

Nazia Selzner; Nigel Girgrah; Les Lilly; Maha Guindi; Markus Selzner; George Therapondos; Oyedele Adeyi; Ian D. McGilvray; Mark S. Cattral; Paul D. Greig; David R. Grant; Gary A. Levy; Eberhard L. Renner

Hepatitis C recurs universally after liver transplantation (LT). Whether its progression differs after live donor liver transplantation (LDLT) and deceased donor liver transplantation (DDLT) is still debated. We retrospectively analyzed 201 consecutive LTs performed at our institution for hepatitis C–related end‐stage liver disease between April 2000 and December 2005 (46 LDLTs and 155 DDLTs). Patients were followed with protocol biopsies for medians of 29 (LDLT) and 39 months (DDLT; P = 0.7). Although overall graft and patient survival did not differ, the mean fibrosis stage (Metavir) was significantly higher at 12 to 48 months post‐LT (all P < 0.05), and the rate of fibrosis progression tended to be faster after DDLT than LDLT (0.19 versus 0.11 stage/year, P = 0.05). In univariate analysis, donor age, cold ischemic time, and DDLT were significantly associated with a fibrosis stage ≥ 1 at 1 year and a fibrosis stage of 3 or 4 at 2 years post‐LT. In multivariate analysis, however, donor age was the sole variable independently associated with both surrogate outcomes. Thus, donor age > 45 years carried a relative risk of 8.17 (confidence interval = 2.6–25.5, P = 0.001) for reaching fibrosis stage 3 or 4 at 2 years post‐LT. In conclusion, donor age, rather than the transplant approach, determines the progression of recurrent hepatitis C after LT. LDLT, allowing for the selection of younger donors, may particularly benefit hepatitis C patients. Liver Transpl 14:1778–1786, 2008.


Liver Transplantation | 2008

Sirolimus in liver transplant recipients with renal dysfunction offers no advantage over low‐dose calcineurin inhibitor regimens

Derek DuBay; R. Smith; Kenneth G. Qiu; Gary A. Levy; Leslie B. Lilly; George Therapondos

The purpose of this study is to review the clinical experience with sirolimus immunosuppression in liver transplant patients with calcineurin inhibitor–induced chronic renal insufficiency. The study design is a case‐control retrospective series. Fifty‐seven liver transplant patients with renal insufficiency that were started on sirolimus at greater than 90 days postoperatively and treated for more than 90 days were identified. A control group of 57 patients maintained on low‐dose calcineurin inhibitors, matched for gender, year of transplant, and baseline creatinine clearance, was also identified. There were no significant differences in the absolute creatinine clearance values between the sirolimus and control groups from 6 months before sirolimus conversion to 12 months after sirolimus conversion. Patients exposed to calcineurin inhibitors for more than 5 years or those with an initial creatinine clearance of less than 30 mL/minute who were converted to sirolimus did worse than control patients maintained on low‐dose calcineurin inhibitors. Progression to renal replacement therapy, episodes of acute and chronic rejection, and death were similar between the sirolimus and control groups. The overall prevalence of side effects was significantly higher in the sirolimus group compared with the control group, although these were generally tolerable in most patients. In conclusion, this study suggests that conversion to sirolimus in liver transplant patients with chronic renal insufficiency is associated with stabilization of renal function but confers no additional benefit to low‐dose calcineurin inhibitor regimens and may in fact be disadvantageous in patients with a creatinine clearance of less than 30 mL/minute. Liver Transpl 14:651–659, 2008.


European Journal of Gastroenterology & Hepatology | 2005

The clinical course of ulcerative colitis after orthotopic liver transplantation for primary sclerosing cholangitis: further appraisal of immunosuppression post transplantation.

Gwo-Tzer Ho; Alexandra J. Seddon; George Therapondos; Jack Satsangi; Peter C. Hayes

Background and aims The course of ulcerative colitis (UC) following orthotopic liver transplantation (OLT) for primary sclerosing cholangitis (PSC) is unclear. We documented the nationwide experience of the course of UC, before and after OLT for PSC. Methods and results A total of 470 liver transplants were performed for 413 patients between 1992 and 2003, in the Scottish Liver Transplantation Unit, UK. Twenty-six patients had co-existing UC/PSC. Of these, data from 20 patients were studied over a median period of 11.9 years before OLT and 4.4 years after OLT; of the others, four patients required colectomy prior to OLT, one died within 7 days of transplant, and one developed UC after transplant. A significantly higher relapse rate (number of relapses/year of follow-up) was seen after OLT (median 1.0 versus 0.3; interquartile range, 0.10–1.42 and 0.01–0.40, respectively; P=0.007). The corticosteroids requirement (number of courses/year of follow-up) after OLT was also significantly higher (0.40 versus 0.10; interquartile range, 0.51–1.13 and 0.05–0.12, respectively; P=0.003). Twenty per cent of patients (4/20) became corticosteroid dependent after OLT. Thirty-five per cent of patients (7/20) underwent colectomy after OLT: three for severe disease and four for neoplasia/dysplasia. Five patients (19%) developed neoplasia following OLT. Conclusion Despite immunosuppression, UC follows a more aggressive clinical course after OLT and is associated with a high rate of neoplasia.

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Nigel Girgrah

University Health Network

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Ian C. Carmody

University of California

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Natalie Bzowej

California Pacific Medical Center

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