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C Margarit

Publications and source records attributed to C Margarit.

At least 37 records · Page 2Linked to original sources
PubMed2001

Role of Doppler echocardiography in the assessment of portopulmonary hypertension in liver transplantation candidates.

BACKGROUND: Portopulmonary hypertension is a severe complication of liver cirrhosis that carries a high risk for posttransplantation mortality. We aimed at evaluating the utility of Doppler echocardiography in screening for portopulmonary hypertension in liver transplantation candidates. METHODS: One hundred seven cirrhotic patients candidates for liver transplantation were studied by Doppler echocardiography and subsequently, by cardiac catheterization at transplantation. Two parameters were estimated by Doppler: systolic pulmonary arterial pressure (SPAP) derived from tricuspid regurgitation and the pulmonary acceleration time. Portpulmonary hypertension was suspected when SPAP was > or = 40 mm Hg and/or pulmonary acceleration time < 100 ms. RESULTS: Portpulmonary hypertension was suspected by Doppler study in 17 patients (15%). However, portopulmonary hypertension (mean pulmonary arterial pressure > or = 25 mm Hg and pulmonary vascular resistance > 120 dynes.s/cm5) was confirmed by the hemodynamic study in five patients (4.7%). Sensitivity and specificity of Doppler echocardiography for detecting portopulmonary hypertension was 100 and 88%, respectively, with a positive predictive value of 30%. The diagnostic accuracy of pulmonary acceleration time alone (96%) was better than pulmonary arterial pressure alone (90%). CONCLUSIONS: Doppler echocardiography, and especially the determination of pulmonary acceleration time, is a useful screening method for portopulmonary hypertension in patients with liver cirrhosis who are candidates for liver transplantation.

Adult↗
PubMed2001

The development of low-grade cerebral edema in cirrhosis is supported by the evolution of (1)H-magnetic resonance abnormalities after liver transplantation.

BACKGROUND/AIMS: Liver failure may cause brain edema through an increase in brain glutamine. However, usually standard neuroimaging techniques do not detect brain edema in cirrhosis. We assessed magnetization transfer ratio and (1)H-magnetic resonance (MR) spectroscopy before and after liver transplantation to investigate changes in brain water content in cirrhosis. METHODS: Non-alcoholic cirrhotics without overt hepatic encephalopathy (n=24) underwent (1)H-MR of the brain and neuropsychological tests. (1)H-MR results were compared with those of healthy controls (n=10). In a subgroup of patients (n=11), the study was repeated after liver transplantation. RESULTS: Cirrhotic patients showed a decrease in magnetization transfer ratio (31.5+/-3.1 vs. 37.1+/-1.1, P<0.01) and an increase in glutamine/glutamate signal (2.22+/-0.47 vs. 1.46+/-0.26, P<0.01). The increase in glutamine/glutamate signal was correlated to the decrease in magnetization transfer ratio and to neuropsychological function. Following liver transplantation, there was a progressive normalization of magnetization transfer ratio, glutamine/glutamate signal and neuropsychological function. Accordingly, correlations between these variables were lost after liver transplantation. CONCLUSIONS: Cirrhotic patients show reversible changes in magnetization transfer ratio that are compatible with the development of low-grade cerebral edema. Minimal hepatic encephalopathy and low-grade cerebral edema appear to be the consequences of the metabolism of ammonia in the brain.

Ammonia↗
PubMed2001

[Comparative study of reduced-size and whole liver transplantation in children].

It is difficult to find adequate donors for many children with low weight. In order to increase the pool size of donors and decrease mortality on the waiting list, several reduction techniques have been developed in the last years (reduced, segmental and split liver). The aim of this study is to compare morbility and mortality in our serie between children who received a full-size liver and those who received a partial one. We retrospectively compared 27 cases of reduced-size liver transplants (RLTx) with 102 cases of full-size liver transplants (FLTx) performed between june of 1985 and february of 2000. Mean age in RLTx was 38.1 months (range 6-144) vs 70.8 months (range 5-192) in FLTx. Mean weight was 11.9 k (range 5.8-30) in RLTx vs 20.48 k (range 4.4-68) in FLTx. Mean donor/recipient body ratio was 4.88 in RLTx and 2.03 in FLTx. The indication of transplantation was urgent in 14 patients (51.8%) from the RLTx group and in 12 (11.7%) from the FLTx one. The requirements of transfusions during surgery was greater in the RLTx (177 cc/kg of RBC transfusions vs 124 cc in FLTx). There was no differences between both groups regarding other postoperative complications (portal thrombosis, need of reintervention and biliary complications). Arterial thrombosis was observed only in FLTx (12 cases). Graft survival at 3 months was 49% for the RLTx and 73% for the FLTx. It was 43% and 67%, respectively, at 1 year, and 43% and 53% at 5 years after liver transplantation (p = 0.06). If we consider only elective transplants, survival was 72% for RLTx and 75% for the FLTx at 3 months. Although survival is lower in the RLTx group, the difference is not significant. If we consider only the elective transplants, survival is almost the same in both groups. The reduction techniques are a good method to decrease mortality in the waiting list without increasing post-transplant morbidity and mortality.

Child↗
PubMed2001

[Improvement in the results of surgical resection of hepatocellular carcinoma].

AIM: To present the results of hepatectomies performed for hepatocellular carcinoma in a specialist unit and to compare the results of an initial period (1987-1993) with those obtained in a second period (1995-2000) in which the indications were limited to Child class A patients without portal hypertension. During the second period technical improvements such as intermittent selective hilar clamping and greater hiliar restrictions on transfusions were introduced. PATIENTS AND METHODS: One hundred and ten hepatectomies were performed in 105 patients with hepatocellular carcinoma in our unit over a 12-year period. Eighty percent of the tumors occurred in cirrhotic livers, mainly caused by hepatitis C virus. In the second period, upper gastrointestinal endoscopy was systematically performed to study the presence of varices. Hemodynamics studies were optionally performed to rule out portal hypertension. RESULTS: In the second period larger tumors were resected, a greater number of major hepatectomies were performed due to the increased frequency of hepatocellular carcinoma in non-cirrhotic liver, and fewer patients underwent transfusion. Early mortality was reduced from 21% to 1.8% and mean survival significantly increased from 37 to 52 months. Actuarial survival increased from 64% to 91% at 1 year and from 23% to 52% at 5 years in the first and second periods, respectively. Disease-free survival also increased significantly from 53% and 84% at 1 year and 27% and 40% at 5 years in the first and second periods, respectively. Analysis of the results in cirrhotic patients also showed a statistically significant improvement in early mortality and survival. Multivariate analysis of prognostic factors for survival demonstrated that the absence of blood transfusion, patients who underwent resection in the second period and the presence of pseudocapsules were independent factors for increased survival. CONCLUSIONS: The results of liver resection for hepatocellular carcinoma improved significantly due to the reduction in early mortality produced by more rigorous patient selection and the introduction of technical improvements.

Adult↗
PubMed2001

Outcome and hepatic hemodynamics in liver transplant patients with portal vein arterialization.

UNLABELLED: Few cases of successful portal vein arterialization in orthotopic and auxiliary liver transplantation have been reported. AIM: To evaluate the effect of portal vein arterialization on hepatic hemodynamics and long-term clinical outcome in three patients undergoing liver transplantation. METHODS: Two patients with extensive splanchnic venous thrombosis received an orthotopic liver transplant and one with fulminant hepatic failure received an auxiliary heterotopic graft. Portal vein arterialization was performed in all cases. RESULTS: One patient died 4 months after transplant and two are still alive. Auxiliary liver graft was removed 3 months post-transplant when complete native liver regeneration was achieved. Immediate post-transplant liver function was excellent in all cases. Only one patient developed encephalopathy and variceal bleeding owing to prehepatic portal hypertension secondary to arterioportal fistula 14 months after transplant. He was successfully treated by embolization of the hepatic artery. Hepatic hemodynamic measurements demonstrated a normal pressure gradient between wedged and free hepatic venous pressures in all cases. Liver biopsy showed acceptable graft architecture in two cases and microsteatosis in one. CONCLUSIONS: Liver transplantation with portal vein arterialization is an acceptable salvage alternative when insufficient portal venous flow to the graft is present. The double arterial supply does not imply changes in hepatic hemodynamics, at least in the early months post-transplant.

Adult↗
PubMed2000

Analysis of risk factors following pediatric liver transplantation.

Several recipient, donor and operation factors as well as postoperative complications related to patient survival after liver transplantation (LT) in children were studied by univariate and multivariate analyses. In a 13-year period, 103 patients under 15 years of age underwent 120 LT; the mean age was 63 months and 36% were under 2 years of age. Indications for LT were cholestatic disease in 68 (56%), metabolic diseases in 18 (14%), fulminant hepatic failure in 8 (7.5%), cirrhosis in 7 (5.8%), and retransplants in 17 (14%). Whole liver was transplanted in 79% of cases and partial liver in 21%. Actuarial survival at 1, 5, and 10 years was 70%, 61%, and 57%, respectively. United Network of Organ Sharing (UNOS) I recipients (RR = 2.7), primary non-function (PNF) (RR = 13.9), and hepatic artery thrombosis (HAT) (RR = 3.8) were independent factors for lower patient survival in multivariate analysis. Thus, in our experience, postoperative mortality as a consequence of the patient's condition before transplantation, or complications such as PNF or HAT, are the major causes of decreased survival in pediatric LT.

Adolescent↗
PubMed2000

Auxiliary heterotopic liver transplantation with portal vein arterialization for fulminant hepatic failure.

Auxiliary liver transplantation for patients with fulminant hepatic failure supports the patient's failing liver for a period of time until the native liver (NL) has recovered and immunosuppression can be withdrawn. Auxiliary heterotopic liver transplantation (AHLT) with portal vein arterialization (PVA) has several advantages over auxiliary orthotopic liver transplantation: NL resection is not required, and the hepatic hilum is left untouched; thus, the chances of liver regeneration are optimal. The successful application of emergency AHLT with PVA in a young patient who developed toxic fulminant hepatic failure caused by tuberculostatic drugs is described. Two and one-half months after the procedure, the NL had completely regenerated; the graft was removed, and immunosuppression was suspended.

Adult↗
PubMed2000

Comparative study of sequential combinations of paclitaxel and methotrexate on a human bladder cancer cell line.

We investigated the cytotoxic effect of different sequential combinations of paclitaxel (Taxol, TX), an antimicrotuble agent, and methotrexate (MTX), a potent inhibitor of dihydrofolate reductase, on a human bladder cancer cell line (T24). The results obtained with a colony-forming assay 5 days after 24 hr of exposure to TX alone showed a strong decline in colony growth up to a concentration of 6 nM. There was a plateau phase at TX concentrations ranging from 6 to 10 nM. The IC50 values found with the different dosing sequences and 24-hr exposure to the drugs were 0.24 microM for MTX alone, 3.49 nM for TX alone, 3.84 nM for TX followed by MTX, 3.75 nM for TX and MTX simultaneously, and 2.10 nM for MTX followed by TX. The cytotoxic effect due to drug interactions in the different sequential combinations was evaluated by an algebraic method. All the combination sequences were found to be synergistic (combination index [CI] < 1) at low TX concentrations. An antagonistic effect (CI > 1) was obtained at higher TX concentrations. Our data demonstrate that the T24 cell line is sensitive to TX and that the cytotoxic effect is enhanced to different degrees depending on the treatment sequence when TX is combined with MTX. These findings could have implications in the design of appropriate administration schedules of these two drugs for the treatment of bladder cancer.

Antimetabolites, Antineoplastic↗
PubMed1999

Outcome of hepatitis C virus-associated membranoproliferative glomerulonephritis after liver transplantation.

BACKGROUND: Hepatitis C virus was the most frequent cause of liver failure requiring liver transplantation in our series. Hepatitis C virus infection has been associated with glomerulonephritis and, more frequently, type I membranoproliferative glomerulonephritis. Renal disease in patients with liver failure is often clinically silent and difficult to diagnose; thus, biopsy is required to establish the diagnosis. Our aim was to study the evolution of six patients diagnosed with membranoproliferative glomerulonephritis some months before liver transplantation. METHODS: Liver transplantation alone was performed in four patients and combined liver-kidney transplantation in the remaining two, who were on hemodialysis for kidney failure. These patients were followed for a mean of 38.3+/-7.8 months. Evolution of proteinuria, renal function, hepatic function, and hepatitis C virus activity was studied. RESULTS: In the four patients who underwent liver transplantation alone, proteinuria became negative initially and renal function remained stable. Proteinuria reappeared and renal function was altered in two of these patients at 17 and 36 months of follow-up, respectively, coinciding with a recurrence of active chronic hepatitis. In the two patients who received a combined liver-kidney transplant, proteinuria became negative, and their renal grafts currently maintain normal renal function. CONCLUSIONS: Membranoproliferative glomerulonephritis does not constitute an absolute contraindication for liver transplantation alone; combined liver-kidney transplantations are reserved for patients with end-stage kidney failure. Proteinuria is reversed after liver transplantation, and recurrence seems to be associated with severe hepatitis C virus hepatic allograft disease relapse.

Adult↗
PubMed1999

Analysis of the complications of the piggy-back technique in 1,112 liver transplants.

BACKGROUND: The "piggy-back" technique has gained acceptance in adult orthotopic liver transplantation during the last few years, especially in European countries. At the moment, however, there is controversy over advantages or specific complications (suprahepatic thrombosis or narrowing, etc.) related to this surgical technique. The aim of this study is to know of the immediate per-and postoperative morbidity and mortality rates in 1112 orthotopic liver transplantations performed with a vena cava preservation technique. METHODS: All liver transplant units in Spain were sent a questionnaire on retrohepatic vena cava preservation during orthotopic liver transplantation. The number of orthotopic liver transplantations that had been performed in the seven centers that answered the questionnaire, because the beginning of the program, was 1674, with the vena cava preservation technique used in 1112. RESULTS: Twenty-eight patients (2.5%) had intraoperative complications related to the vena cava preservation technique, which were treated during the operation. Eleven patients (1%) had early postoperative complications (first week), the most frequent (nine cases) being an acute Budd-Chiari syndrome in the first 48 hr. Three patients developed symptoms of massive ascites between 2 and 3 months (late postoperative complications), with patency of the retrohepatic cava verified by cavography. A hemodynamic study revealed a hyperpressure at the suprahepatic veins. This chronic Budd-Chiari syndrome was controlled in all patients with diuretics. Only six patients (0.5%) died as a result of complications related to the "piggy-back" technique. These complications were more frequent when venous reconstruction was done using two suprahepatic veins than when the three veins were used (P<0.001). CONCLUSIONS: The vena cava preservation technique can be used routinely in orthotopic liver transplantation because it is safe and efficient and involves few surgical complications especially if for venous reconstruction we use the patch obtained by joining the three suprahepatic veins.

Adult↗
PubMed1999

Liver transplantation in patients with splenorenal shunts: intraoperative flow measurements to indicate shunt occlusion.

Two patients with previous distal splenorenal shunts (DSRSs) performed 6 years earlier underwent liver transplantation (LT). A preoperative selective mesenteric artery angiogram showed collateral veins draining mesenteric venous flow into the shunt. Intraoperative flow measurements were performed to assess the steal of portal venous flow by the shunt and determine the need for shunt occlusion. Portal vein, hepatic artery, and shunt flows were measured by ultrasound transit-time flow probes in the native liver and after graft implantation with and without temporary shunt occlusion. Hemodynamic studies showed that long-standing DSRSs are high-flow shunts that steal portal flow. After graft implantation, DSRS flows remained high. Occlusion of the shunts produced an increase in portal vein flow at an amount similar to those of splenorenal shunt. Thus, the flow measurements showed persistent steal by the shunts after graft implantation and, therefore, the DSRSs were occluded but splenectomy was not performed. We conclude that the decision to occlude a DSRS should be based on the demonstration of steal of portal flow by the shunt and reversibility once the shunt is occluded. Splenectomy is not required when the DSRS is occluded.

Adult↗
PubMed1999

Serum cholesterol changes in long-term survivors of liver transplantation: a comparison between cyclosporine and tacrolimus therapy.

The aim of this study was to compare the long-term effect of tacrolimus and cyclosporine therapies on serum cholesterol levels in liver transplant recipients. We retrospectively studied 127 consecutive adult liver transplant recipients who survived for at least 1 year after transplantation. Basal immunosuppression consisted of cyclosporine plus prednisone in 100 patients and tacrolimus plus prednisone in 27 patients. Hypercholesterolemia was defined as a fasting serum cholesterol level greater than 220 mg/dL. Mean follow-up was 39 months. No statistical significance was found between cyclosporine- and tacrolimus-treated patients regarding age, sex, diagnosis, and previous cholesterol levels; both groups were similar. Significantly more tacrolimus-treated patients were steroid free in the first and second year of follow-up (tacrolimus, 37% and 63%; cyclosporine, 13% and 32%, respectively; P <.01). In the third year of follow-up, this difference was not significant (77% v 56%). The overall incidence of hypercholesterolemia was 34.6% (44 patients). At the end of the study, hypercholesterolemia was found in 24 of 51 and 14 of 70 patients with and without steroids, respectively (P <.002). Also, mean cholesterol levels were 224 +/- 70 and 191 +/- 48 mg/dL before and after steroid withdrawal, respectively, P <.001. Hypercholesterolemia was found in 43.7% of the patients during cyclosporine plus prednisone therapy compared with 46.1% of the patients during tacrolimus plus prednisone therapy (P <.9). Greater mean cholesterol levels were found in the cyclosporine group, particularly in the second and third years of follow-up (P <.01). Hypercholesterolemia was found in 22% of the patients during cyclosporine monotherapy compared with 15% during tacrolimus monotherapy (P <.5). No differences were found in mean cholesterol levels during follow-up when both monotherapy groups were compared. In conclusion, a lower incidence of hypercholesterolemia was achieved in tacrolimus-treated patients, mainly when steroids were still part of the immunosuppressive treatment.

Cholesterol↗