Influence of antiviral therapy in the long-term outcome of recurrent hepatitis C virus infection following liver transplantation

INTRODUCTION

Severity of recurrent hepatitis C virus (HCV) infection in liver transplant recipients (LTR) is variable and the influence of different factors, including the administration of antiviral therapy in the long-term outcome is controversial.

METHODS

We analyzed the outcome of a cohort of HCV-infected LTR who were transplanted in our institution. Patients were divided into 2 groups (severe and non-severe HCV disease) depending on the presence of a fibrosis score of F ≥ 2 in the Scheuer index and/or fibrosing cholestasic hepatitis (FCH) in a graft biopsy. Risk factors were studied using logistic regression analysis. Survival of patients was estimated using Kaplan-Meier plots. A total of 146 patients were followed for a mean of 58 months.

RESULTS

Fifty-six (34%) patients developed severe HCV disease and showed shorter survival (P < 0.024). Donor age (odds ratio [OR]: 1.04; 95% confidence interval [CI]: 1.02-1.06) and pre-transplant viral load (VL) >10(6) UI/mL (OR: 3.5; 95% CI: 1.42-10.61) were the only factors associated with severe HCV infection. Over-immunosuppression (OR: 2.3; 95% CI: 1.2-4.41) was specifically associated with the development of FCH. Overall, patient survival in recipients who received a full course of anti-HCV therapy was higher than in patients who did not complete antiviral therapy (P = 0.004) or received no treatment (P = 0.007). Patients with non-severe HCV infection have a higher probability of receiving a full course of antiviral therapy (P = 0.033).

CONCLUSION

In conclusion, donor age, pre-transplant VL, and over-immunosuppression were associated with the long-term development of severe HCV recurrence in liver grafts. Administration of a full course of antiviral therapy was associated with better survival.

Epidemiology, risk factors and impact on long-term pancreatic function of infection following pancreas-kidney transplantation

Limited information exists about epidemiology and risk factors of infection following pancreas-kidney transplantation and its impact on long-term pancreatic graft function. A retrospective chart review of episodes of severe infection in consecutive pancreas-kidney transplantations in a single institution was performed to assess the epidemiology, risk factors for infection and their impact on the development of pancreatic graft dysfunction. Ninety-four (81%) of 116 recipients (median follow-up of 1492 days; mean 1594) developed 248 episodes of severe infection. Bacterial infections were present in 208 episodes, with 12% of the isolates resistant to antibiotics used in prophylaxis. There were 40 episodes of fungal infection in 32 patients (28%) (mostly Candida spp), and CMV disease appeared in 20 patients (17%), of which 50% appeared after the third month following surgery. The multivariate analysis identified that surgical re-intervention and the use of steroid pulses were independently associated with the development of any infection. Additionally, pre-transplant evidence of peripheral artery disease, a longer cold ischaemia time and high transfusional requirements were associated with fungal infections. Cytomegalovirus (CMV) mismatch was independently related to CMV disease and female sex, and bladder drainage of the exocrine pancreas was associated with urinary tract infection. At the end of follow-up, 29 patients (25%) had developed severe pancreatic graft dysfunction, and fungal infection was independently associated with it. Our study identifies a subset of pancreas-kidney transplant recipients at a higher risk of developing severe infection. Fungal infection is an independent risk factor for the development of severe pancreatic graft dysfunction.

Liver transplantation from anti-hepatitis C virus-positive donors: our experience

BACKGROUND

Hepatitis C (HCV) is among the most common causes of end-stage liver disease worldwide. The donor shortage leads us to consider alternative organ sources such as HCV-positive donors. The outcomes of these transplants must be evaluated thoroughly since there is universal recurrence of disease among HCV-positive liver transplant recipients.

METHODS

From January 2005 to April 2011, we performed 143 liver transplants (OLT) to treat end-stage liver disease secondary to HCV infection. Thirteen patients (9,1%) received livers from HCV-positive donors. A control group consisted of 130 HCV-positive patients who underwent OLT during the same period with organs from HCV-negative donors. Donor HCV status was assessed by 2 tests: HCV antibodies and viral load. Not only recipient and graft survivals were analyzed, but also frequency, timing and severity of hepatitis recurrence.

RESULTS

Among 143 transplants performed in HCV-positive recipients during a 6-year period from January 1, 2005, to April 30, 2011, 9.1% of patients received an organ from an anti-HCV-positive donor, 72.7% of whom showed a negative viral load. The vast majority (80%) of our patients suffered hepatitis during their follow-up, 22.4% of which were severe cases.

CONCLUSIONS

No significant difference in patient or graft survival was observed between the 2 groups. A high percentage of grafts with initial positive serology for HCV showed no viral replication. Grafts from HCV-positive donors can be considered to be a safe, effective source for liver donation.

Prospective versus retrospective ECG-gating for 64-detector computed tomography of the coronary venous system in pigs

BACKGROUND

Multidetector computed tomography (MDCT) provides a non-invasive anatomic description of the coronary veins that may be useful in patients candidates to cardiac resynchronization. Prospective gating reduces radiation exposure but its impact on image quality is unknown is this setting.

AIMS

This study compared image quality and reliability of MDCT angiography of the coronary veins between prospective and retrospective gating.

METHODS

Seven anaesthetized pigs underwent 64-detector row MDCT with prospective and retrospective ECG-gating. MDCT scans were evaluated for visibility of the veins, estimated radiation dose and vein characteristics. Inter- and intra-observer reproducibility was calculated.

RESULTS

Visibility grades of all veins were significantly decreased in prospective (0.82 ± 0.6) compared to retrospective gating (1.68 ± 0.9; P<0.001), the lateral vein being missed in two cases when using prospective vs. retrospective gating. The maximal vein length was significantly increased when using retrospective gating (P=0.015). Inter-observer but not intra-observer reproducibility was dependent on the gating technique for the maximal length and contrast-to-noise ratio (P=0.003 for both). Heart rate was 82 ± 13 bpm and 86 ± 11 bpm during retrospective and prospective ECG-gating (P=ns) despite full dose of atenolol titration.

CONCLUSION

Retrospective gating seems to be superior to prospective gating MDCT to describe the coronary venous system but the conclusions of our study should be confined to high heart rate condition.

Intracoronary autologous mononucleated bone marrow cell infusion for acute myocardial infarction: results of the randomized multicenter BONAMI trial

AIMS

Intracoronary administration of autologous bone marrow cells (BMCs) leads to a modest improvement in cardiac function, but the effect on myocardial viability is unknown. The aim of this randomized multicentre study was to evaluate the effect of BMC therapy on myocardial viability in patients with decreased left ventricular ejection fraction (LVEF) after acute myocardial infarction (AMI) and to identify predictive factors for improvement of myocardial viability.

METHODS AND RESULTS

One hundred and one patients with AMI and successful reperfusion, LVEF ≤45%, and decreased myocardial viability (resting Tl201-SPECT) were randomized to either a control group (n = 49) or a BMC group (n = 52). Primary endpoint was improvement of myocardial viability 3 months after AMI. Baseline mean LVEF measured by radionuclide angiography was 36.3 ± 6.9%. Bone marrow cell infusion was performed 9.3 ± 1.7 days after AMI. Myocardial viability improved in 16/47 (34%) patients in the BMC group compared with 7/43 (16%) in the control group (P = 0.06). The number of non-viable segments becoming viable was 0.8 ± 1.1 in the control group and 1.2 ± 1.5 in the BMC group (P = 0.13). Multivariate analysis including major post-AMI prognostic factors showed a significant improvement of myocardial viability in BMC vs. control group (P = 0.03). Moreover, a significant adverse role for active smoking (P = 0.04) and a positive trend for microvascular obstruction (P = 0.07) were observed.

CONCLUSION

Intracoronary autologous BMC administration to patients with decreased LVEF after AMI was associated with improvement of myocardial viability in multivariate-but not in univariate-analysis. A large multicentre international trial is warranted to further document the efficacy of cardiac cell therapy and better define a group of patients that will benefit from this therapy.

CLINICAL TRIAL REGISTRATION INFORMATION

URL: http://www.clinicaltrials.gov. Unique identifier NCT00200707.

Leukocyte SPECT/CT for detecting infection of left-ventricular-assist devices: preliminary results

We report our experience with using integrated molecular and anatomic hybrid imaging to assess infection in patients who have a left-ventricular-assist device (LVAD).

METHODS

Thirteen (99m)Tc-exametazime-leukocyte planar and SPECT/CT scans were obtained for 8 consecutive patients who had an implanted LVAD. SPECT/CT was used to assess suspected device-related infections (n = 8) and to evaluate the efficiency of current antibiotic therapy (n = 5).

RESULTS

Device-related infection was seen on 8 of the 13 scans. SPECT/CT was positive for infection in all 8 patients, whereas planar scans were positive in 6 of 8. SPECT/CT provided relevant information on the extent of infection and its exact location in all patients. Additional distant infectious foci were demonstrated in 3 of 13 patients.

CONCLUSION

SPECT/CT led to an accurate diagnosis of LVAD-related infection, revealing both anatomic location and extent. This noninvasive approach could lead to improved therapeutic strategies.

[Prognostic value of pretherapeutic 18F-FDG PET/CT in cancer of the uterine cervix: a retrospective study of 53 patients]

OBJECTIVES

Assessment of prognostic value of pretherapeutic (18)F-FDG PET/CT (PET).

PATIENTS AND METHODS

Retrospective study of 53 patients with invasive uterine cervix carcinoma. Each patient has been evaluated with pretherapeutic whole-body FDG PET/CT and pelvic MRI. Minimal follow-up lasted for 1 year. On PET/CT, we have visually analyzed metabolism of primary tumor, pelvic and para-aortic lymph nodes in comparison with surrounding structures. We have compared prognostic factors as pretherapeutic haemoglobin rate, FIGO staging, MRI and PET/CT data using Mann-Whitney univariate analysis and Cox multivariate analysis.

RESULTS

Para-aortic lymph node abnormal uptake on PET/CT was the only independent predictor of progression-free survival. Pelvic lymph node involvement on PET/CT was the only independent predictor of overall survival. MRI did not provide any additional information.

DISCUSSION AND CONCLUSION

Lymph node involvement visually assessed by (18)F-FDG PET/CT was the most significant prognostic factor for overall and progression-free survival.

Diagnostic and prognostic value of myocardial perfusion gated SPECT in orthotopic heart transplant recipients

BACKGROUND

Cardiac allograft vasculopathy (CAV) limits long-term survival after heart transplantation. Diagnostic and prognostic value of gated single photon emission computed tomography (gated SPECT) has not been documented in this setting.

METHODS AND RESULTS

We identified 110 consecutive heart transplant recipients (with transplantation >18 months) who underwent stress-rest gated SPECT and coronary angiography within 1 month, and were clinically monitored in a single heart transplantation center. Visual scoring of perfusion and wall motion images used a 16-segment model. Left ventricular function was automatically calculated. Coronary angiography was normal in 64 patients (58%) and abnormal in 46 (any CAV, 42%), of whom 19 had severe stenoses. Sensitivity and negative predictive (NPV) value were .63 and .75 for identification of any CAV, and .84 and .96 for severe CAV. Cox regression analysis showed that independent predictors of cardiac death and retransplantation were the presence of any angiographic CAV lesions (RR = 8.816, P = .043) and a stress perfusion defect >3 segments (RR = 5.607, P = .0053). A stress perfusion defect >3 segments predicted the need for late coronary revascularization >2 months (RR = 6.11, P = .0002).

CONCLUSIONS

We conclude that perfusion gated SPECT is a useful noninvasive screening test and may be proposed to help identify heart transplant recipients with a high risk of poor clinical outcome. A normal gated SPECT was associated with a low risk of cardiac hard event and might alleviate the need for coronary angiography.

Compative study of bladder versus enteric drainage in pancreas transplantation

INTRODUCTION

There is some controversy concerning the choice of best technique for drainage of exocrine secretions in pancreas transplantation. We compared patients with bladder drainage (BD) versus those with enteric drainage (ED).

PATIENTS AND METHODS

From March 1995 to September 2008, 118 patients (68 men and 50 women) of overall mean age of 37.8 +/- 7.8 years underwent pancreas transplantation. There were 109 simultaneous pancreas-kidney, and 9 pancreas after kidney procedures. Recipients were divided in a BD (n = 66 patients) and an ED group (n = 52).

RESULTS

Donor characteristics were similar in both groups. Thirty-two patients (48.5%) of the BD group versus none in the ED group experienced urinary tract infections (UTI; P < .001), and 16 patients (24.2%) BD versus 15 (29.4%) ED developed intraabdominal infections (P = NS). The overall rate of relaparotomies was 33.9% (n = 40): 34.8% (n = 23) in the BD versus 32.7% (n = 17) in the ED group (P = NS). Thirty patients (25.4%) lost their pancreas grafts: 21 (31.8%) in the BD group versus 9 (17.3%) in the ED group (P = .055). The acute rejection rates were 12.7%; namely, 15.2% in the BD versus 9.8% in the ED (P = NS). Three-year patient and graft survivals were equivalent in both groups: 96.1% and 65.3% in the BD versus 89.0% and 74.0% in the ED group, respectively (P = NS).

CONCLUSIONS

ED is a good alternative to BD for drainage of pancreatic graft exocrine secretions because both techniques have the same patient and graft survival, but BD is associated with a significantly higher rate of UTI and urologic complications.

Urinary 1-hydroxypyrene and PAH exposure in 4-year-old Spanish children

AIMS

Exposure to polycyclic aromatic hydrocarbons (PAH), among the main compounds present in polluted urban air, is of concern for children's health. Childhood exposure to PAH was assessed by urinary monitoring of 1-hydroxypyrene (1-OHP), a pyrene metabolite, investigating its association with exposure to air pollution and other factors related to PAH in air.

METHODS

A group of 174 4-year-old children were recruited and a questionnaire on their indoor and outdoor residential environment was completed by parents. At the same time, environmental measurements of traffic-related air pollution (NO2) were carried out. A urine sample was collected from each child in order to analyze 1-OHP using HPLC with fluorescence detection, correcting for creatinine concentrations. Non-parametric tests and regression analyses were used to identify environmental factors that influence 1-OHP excretion.

RESULTS

Mean urinary 1-OHP concentration was 0.061 micromol/mol creatinine, ranging from 0.004 to 0.314 micromol/mol. Non-parametric tests and regression analysis showed positive and significant associations (P<or=0.05) between 1-OHP and predicted residential exposure to NO2 (which was based on outdoor environmental measurements and geo-statistical analysis), self-reported residential vehicle traffic, passive smoking and cooking appliance. 1-OHP levels tended to be higher among children living in urban areas (0.062 micromol/mol vs. 0.058 micromol/mol for children living in rural areas) but differences were not significant (P=0.20).

CONCLUSION

In Southern Spain, concentrations of urinary 1-OHP were in the lower range of those generally reported for children living in non-polluted areas in Western Europe and the USA. Traffic-related air pollution, passive smoking and cooking appliance influenced urinary 1-OHP level in the children, which should be prevented due to the health consequences of the inadvertent exposure to PAH during development.

Cardiac 123I-MIBG scintigraphy in heart failure

This review focuses on myocardial [(123)I]mIBG imaging in patients with cardiomyopathy and heart failure (HF). In particular, the potential role of myocardial (123)I-mIBG scintigraphy in the prediction of potentially fatal arrhythmic events is described. A growing body of evidence supports the use of cardiac sympathetic innervation imaging, specifically using (123)I-mIBG, to risk stratify patients with HF. Cardiac sympathetic imaging can help to improve understanding of the mechanisms responsible for increased sympathetic activity in HF, and how sympathetic over-activity exerts its deleterious actions. Eventually, this may result in more effective therapies and, thereby, better outcome for these patients. Assessment of cardiac sympathetic activity could also contribute to a more appropriate selection of individual patients for implantable cardioverter-defibrillators (ICD).

Pancreas preservation with the University of Wisconsin versus Celsior solutions

INTRODUCTION

The use of Celsior solution for organ preservation has not been thoroughly studied in pancreas transplantation. The aim of this study was to compare University of Wisconsin and Celsior solutions for preservation of pancreas grafts.

PATIENTS AND METHODS

From March 1995 to December 2005, 72 patients with type 1 diabetes underwent pancreas transplantation. There were 42 men and 30 women, with a mean age at transplantation of 38.1 +/- 7.5 years (range: 27 to 55 years), and a mean duration of diabetes of 22.5 +/- 6.6 years. Recipients were classified into two groups according to the preservation solution: (A) Celsior (n = 28, 38.9%) and (B) Wisconsin (n = 44, 61.1%).

RESULTS

The donor and recipient characteristics were similar in both groups. There were five cases of venous thrombosis in the Wisconsin group and two in the Celsior group (P = NS). The venous drainage technique in the former group was portocaval in 19 patients and portoiliac in 25; in the Celsior group, portocaval in 23 patients and portoiliac in five (P = .001). Enteric drainage was used in 19 patients from the Celsior group and 17 patients from the Wisconsin group (P = .01). Actuarial 2-year graft survival was 74.6% in the Wisconsin group and 77.4% in the Celsior group (P = NS).

CONCLUSIONS

No differences were observed in venous thrombosis between the two groups. The lower rate of venous thrombosis with the portocaval technique was related to the type of venous drainage rather than the type of preservation solution. Celsior solution may be considered as good as Wisconsin solution for pancreas transplantation.

Hepatic vein reconstruction in living donor liver transplantation

INTRODUCTION

Living donor liver transplantation has emerged as a response to the cadaveric graft shortage, especially for adult recipients. Both right and left liver grafts are widely used, although some technical problems remain unresolved. Herein we describe our technique for reconstruction of the venous outflow in living donor liver transplantation.

METHODS

From April 1986 to September 2004, 1012 liver transplantations were performed including 30 living donor liver transplantations between April 1995 and September 2004. We have selected the first 28 cases to ensure a mean follow-up of 21.07 +/- 13.11 months. We transplanted 18 right lobe grafts, 7 left lobe grafts, and 3 left lateral segment grafts. A surgical technique is described herein.

RESULTS

No venous outflow obstruction developed among living donor liver transplantation recipients.

CONCLUSION

We recommend reconstruction of the hepatic veins in living donor liver transplantation including joining together the three hepatic veins in the recipient to avoid venous outflow obstruction.

Modulation of hepatocyte growth factor plasma levels in relation to the dose of exogenous heparin administered: an experimental study in rats

INTRODUCTION

Partial liver transplantation has been consolidated to be a valid treatment option. We sought to understand the factors that modulate and may be harnessed to accelerate hepatocyte regeneration. We sought to determine the impact of heparin on m-hepatocyte growth factor (HGF) plasma concentrations.

MATERIALS AND METHODS

Sixteen rats were assigned to four groups of four animals each: group A, without heparin; group B, 600 IU/kg; group C, 1000 IU/kg, group D, 1400 IU/kg. Blood samples (0.5 mL) were obtained from each rat at baseline and at 30, 60, 120, and 240 minutes. After the samples were centrifuged to separate supernates from the cell phase they were stored at -20 degrees C in the m-HGF reagent and subsequently tested using enzyme-linked immunosorbent assay. Results were analyzed using SPSS 11.5 statistical software.

RESULTS

Among the 16 rats, one died at 110 minutes, just prior to the last extraction. The remaining rats were sacrificed. Mean weight was: 466 +/- 64.24 g with no intergroup differences (P = .149). The comparative results (using Student t test) were: baseline A(1-4) versus A(1-4) 30 minutes: P < .05; baseline A(1-4) versus A(1-4) 60 minutes: P < .05; baseline A(1-4) versus A(1-4) 120 minutes: P = .10 (NS); baseline A(1-4) versus A(1-4) 240 minutes: P = .15 (NS). No significant differences were found among group B: baseline C(1-4) versus C(1-4) 30 minutes and 60 minutes: NS; baseline C(1-4) versus C(1-4) 120 minutes: P < .001; baseline C(1-4) versus C(1-4) 240 minutes: P < .10 (NS). Finally, the results in group D were: baseline D(1-4) versus D(1-4) 30 minutes: NS; baseline D(1-4) versus D(1-4) 60 minutes and 120 minutes: P < .05; baseline D(1-4) versus D(1-4) 240 minutes: P < .0005. When we compared group A to C and D, we detected differences (albeit not when compared to B) with P values = .01. Peak values were obtained at 120 and 240 minutes (225.21 pg/mL and 221.78 pg/mL) among groups C and D.

CONCLUSION

Heparin has a positive effect to increase serum HGF concentrations among rats. The effect was dependent on the administered dose and the time elapsed.

Incidence and risk factors of development of lung tumors after liver transplantation

INTRODUCTION

Lung tumors have been related to tobacco and alcohol. The incidence increases after orthotopic liver transplantation (OLT) especially when it is performed because of alcoholic cirrhosis.

PATIENTS AND METHODS

We analyzed the incidence and risk factors for de novo lung tumors among 701 patients who underwent OLT between April 1986 and July 2004, after exclusion of pediatric recipients and adults who died within 2 months after OLT.

RESULTS

The incidence of de novo lung tumors was 15 patients (2.1%), including 12 (4.3%) who underwent OLT for alcoholic cirrhosis and 3 (0.7%) for nonalcoholic diseases. There were 14 men and 1 woman of mean age at OLT of 50.8 +/- 9.6 years. Mean time from OLT to lung tumor was 83 +/- 43 months (range, 10-184 months). Thirteen patients (86.6%) were heavy smokers before OLT and 8 (61.5%) continued after OLT; 12 patients (80%) were heavy drinkers before OLT. Ten patients were immunosuppressed with CyA and 5 with tacrolimus. Acute rejection episodes before tumor diagnosis occurred in 6 patients (40%). Two patients underwent thoracotomy, but only one was resected. The remaining 13 patients were unresectable because of locally advanced tumor or metastatic disease. Two unresectable patients received palliative chemotherapy. All patients died with a mean survival from tumor diagnosis, of 5.3 months (range, 3 days to 33 months).

CONCLUSION

A significantly higher incidence of lung tumors was observed among patients who underwent OLT for alcoholic cirrhosis, usually diagnosed in advanced stages of poor prognosis and low survival.

Incidence of Pancreas Graft Thrombosis in Portoiliac and Portocaval Venous Anastomosis

BACKGROUND

Pancreas graft thromboses represent more than 70% of all technical failures; multiple risk factors have been implicated. We analyzed the thrombosis rates using portoiliac versus portocaval vein anastomoses.

PATIENTS AND METHODS

The series includes 53 patients who underwent pancreas transplantation: 49 simultaneous pancreas-kidney and 4 pancreas after kidney. There were 27 men and 26 women, of mean age of 37.2 +/- 7.0 years. We compared two groups of recipients that were classified according to venous anastomosis: (A) portoiliac (n = 30), and (B) portocaval (n = 23).

RESULTS

The recipients did not show significant differences in age, gender, or duration of diabetes mellitus, but body mass index was significantly higher among the portocaval group. A bladder-drained pancreas technique was more frequently performed in the portoiliac group (93% of patients) versus an enteric-drained pancreas in the portocaval group (81%; P < .001). Heparinization was performed in 12 recipients: 11 (36.6%) in the portoiliac group and 1 (4.3%) in the portocaval group (P < .01). Vascular graft thrombosis (venous in six and arterial in one) developed in seven patients (13.2%) all in the portoiliac group (23%) (P < .02). Two-year patient survival was 93% in the portoiliac group and 94% in portocaval group (P = NS). Two-year graft survival was 66.6% in the portoiliac group and 85.9% in portocaval group (P = .07).

CONCLUSION

There was no graft thrombosis among patients with a portocaval vein anastomosis.

Effect of perfusion pattern and imaging sequence on gated perfusion SPECT evaluation of myocardial stunning

The aim of this study was to determine the effect of perfusion defect and imaging sequence on the evaluation of myocardial stunning with gated perfusion SPECT.

METHODS

A dynamic mathematic cardiac torso phantom was used to create 100 gated SPECT simulations (50 stress-rest and 50 rest-stress sequences) with a wide range of perfusion defects. No segmental wall motion abnormalities were created. After generating projection images, 2 additional acquisitions were simulated by thresholding the projected data to 25% and 75% of the maximum. Finally, gated SPECT projections were grouped by 2s to generate 2 series of phantoms corresponding to stress-rest and rest-stress imaging sequences. For each sequence, the first dataset was the 25% thresholded gated SPECT. Both 75% thresholded and 100% signal intensity were used as a second dataset. Each simulated gated SPECT image differed from others in the extent of myocardial scar or ischemia, but all had the same end-diastolic volume (EDV) (125 mL), end-systolic volume (ESV) (48 mL), and ejection fraction (EF) (62%). Left ventricular perfusion and function were each assessed using validated software.

RESULTS

Mean stress EDV was decreased when compared with rest-simulated data (111 +/- 4.7 and 112.4 +/- 4.8 mL, respectively; P < or = 0.05), and mean stress ESV was increased when compared with rest-simulated data (44 +/- 4.2 and 42.7 +/- 4 mL, respectively; P < 0.02). The resulting mean stress EF was decreased in the same comparison (60.3% +/- 3.1% and 62% +/- 2.7%, respectively; P = 0.0001). After multivariate analysis, the difference between stress and rest EF was significantly influenced by myocardial infarction (P = 0.0027), severe extent of myocardial ischemia (P = 0.0017), and imaging sequence (P < 0.0001). A > or =5% decrease in EF on stress SPECT (i.e., myocardial stunning) was significantly associated with the stress-rest sequence (chi(2) = 26; P < 0.0001).

CONCLUSION

Perfusion defects and imaging sequence had significant effects on the evaluation of myocardial stunning using gated perfusion SPECT.

Impact of photon energy recovery on the assessment of left ventricular volume using myocardial perfusion SPECT

BACKGROUND

Photon energy recovery (PER) is a spectral deconvolution technique validated for scatter removal in patients and phantom studies. The purpose of this study was to examine the impact of PER on left ventricular volume measurement based on myocardial perfusion single photon emission computed tomography (SPECT).

METHODS AND RESULTS

SPECT acquisitions were performed by use of a static cardiac phantom and in 25 patients after a rest injection of technetium 99m sestamibi by use of multiple energy windows (126-136, 137-144, and 145-154 keV). Data were successively reconstructed with and without PER, by use of iterative reconstruction and post-processing filtering (Butterworth filter; order, 5; cutoff, 0.30 cycles/pixel). Image contrast was evaluated in reconstructed data, and volumes were calculated by use of QGS. PER increased reconstructed image contrast from 62% +/- 2.7% to 84.3% +/- 5.7% in the phantom studies (P <.0001) and from 49% +/- 2% to 73% +/- 2% in patients (P <.0001). Although it remained underestimated (P <.0001), phantom volume was higher after PER correction compared with uncorrected data (50.9 +/- 0.8 mL vs 44.6 +/- 1 mL, P <.0001). The error in volume measurement was decreased by PER correction (16.6% +/- 1.3% vs 27% +/- 1.7% [uncorrected data], P <.0001). In patients, left ventricular volume increased from 83 +/- 10 mL to 91 +/- 10 mL (P <.0001), and the PER-induced volume increase was correlated with the image contrast increase (r = 0.61, P =.001). Finally, the percentage of volume increase was higher in patients with small left ventricular volumes.

CONCLUSIONS

PER has a significant impact on image contrast and left ventricular volume measurement by use of perfusion SPECT. PER improves the accuracy of phantom volume assessment. In patients, volume increase is correlated to image contrast increase and is higher in those with small ventricles.

Quantitative analysis of 99mTc-DMSA during acute pyelonephritis for prediction of long-term renal scarring

This study was performed to evaluate a quantitative method based on (99m)Tc-DMSA renal planar scintigraphy performed during acute pyelonephritis (APN) to detect kidneys at risk of scarring.

METHODS

A total of 43 children (5.8 +/- 3.6 y old [mean +/- SD]) were examined by (99m)Tc-DMSA scintigraphy during (DMSA 1) and 8 +/- 2 mo after (DMSA 2) APN. Two levels of interpretation were performed independently: first, a semiquantitative analysis to classify the kidneys by considering the evolution between DMSA 1 and DMSA 2 (i.e., to determine which kidneys had developed scarring), and second, an automatic quantitative analysis of DMSA 1 to define and to evaluate a predictive index for kidney evolution from DMSA 1 to DMAS 2. The method consisted of determining an automatic threshold for the kidney and then calculating ratios of the count density in a given isocount n% (region of interest containing all the pixels with a value > or = n% of the value of the pixel with the maximal activity value) to the count density in a 20% isocount (C(n%)) and the number of pixels in a given isocount to the number of pixels in a 20% isocount (S(n%)).

RESULTS

All kidneys normal at DMSA 1 remained normal at DMSA 2. For the automatic index, the C(70%) ratio was considered the best index for the prediction of scarring. When this C(70%) ratio was used, a cutoff value of 0.45 was able to predict scarring with a sensitivity of 0.83, a specificity of 0.78, a positive predictive value of 0.85, and a negative predictive value of 0.77.

CONCLUSION

A cutoff value of 0.45 for the C(70%) ratio calculated for (99m)Tc-DMSA scintigraphy performed during APN may be useful for detecting kidneys at risk of scarring.

Plans de Coupe en IRM Cardiaque

The recent developments of synchronized cardiac MRI are a unique opportunity for the radiology community to integrate cardiac imaging. This educational aticle aims to help radiologists and technicians to obtain cardiac planes comparable to those of cardiac ultrasound and gated SPECT. Of course, cardiac planes described herein for MRI also apply to multi-detector CT.

Optimisation of the OS-EM algorithm and comparison with FBP for image reconstruction on a dual-head camera: a phantom and a clinical 18F-FDG study

Iterative reconstruction algorithms, such as the ordered subsets expectation maximisation (OS-EM), are a promising alternative to filtered backprojection (FBP). The aims of this study were first to optimise the OS-EM algorithm in terms of iteration number and to study the usefulness of post-filtering, and second to compare OS-EM and FBP for image reconstruction on a fluorine-18 fluorodeoxyglucose ((18)F-FDG) dual-head camera (DHC). These two goals were addressed using phantom acquisitions. The performances of these algorithms were also studied in patient acquisitions performed on a DHC and a PET on the same day. Phantom experiments were performed on a DHC using a Jaszczak phantom containing six spheres filled with (18)F-FDG, two background levels (0.95, 6.80 kBq/ml) and three object contrasts (5.9, 3.7, 2.7). The reconstruction algorithms were FBP with a Gaussian filter (FWHM 0.5-2 pixel width) and OS-EM using 8-128 equivalent iterations (equivalent to the ML-EM algorithm) with and without Gaussian post-filtering [OS-EM (iterations, pixel width)]. Contrast recovery coefficient (CRC) and noise characteristics were assessed. Twenty-two patients (21 male, one female; age 55+/-15 years) with lung cancer underwent, on the same day, PET (1 h post injection of 37 MBq/kg (18)F-FDG) and DHC acquisitions (3 h post injection). DHC data were reconstructed using six methods: FBP (1), OS-EM (16), (40), (40,1), (64) and (64,1). These sets were evaluated by two observers and compared to PET reconstructed with OS-EM (16). The number of detected lesions and the visual quality were assessed. A marked improvement in CRC was observed with OS-EM as compared with FBP when more than 24 iterations were used. The CRC increased markedly from 8 to 40 iterations and then reached a plateau. The noise was stable until 40 iterations and then increased. The best compromise was obtained for OS-EM (32) and OS-EM (40,1). For the patient study, OS-EM provided images of better visual quality, but with no significant difference in detection sensitivity. OS-EM was superior to FBP in terms of contrast recovery and noise level. The optimal compromise between contrast recovery and noise was obtained for OS-EM (32) and (40,1) on the phantom study. The clinical study showed that OS-EM yielded images of better visual quality but with no improvement in terms of detection of lung cancer.

Live liver donation: a prospective analysis of exclusion criteria for healthy and potential donors

INTRODUCTION

Living donor liver transplantation represents a controversial option to increase the donor pool.

DESIGN

Prospective and descriptive clinical study.

OBJECTIVE

(1) To identify risk factors (exclusion criteria) for live donation; (2) to determine the rate of recipients that benefit from a living donor.

METHODS

Between May 1995 (first adult-to-adult living donor liver transplantation in Spain) and November 2002, we evaluated 74 healthy volunteers and performed 12 living donor liver transplants (no donor mortality).

RESULTS

All actual donors and volunteers are alive and healthy. After a mean time of 3.2+/-0.5 weeks, 72% of potential donors were considered unsuitable for live donation. Exclusion criteria were grouped in three categories: (primary) donor safety reasons (68%); (secondary): ABO mismatch (17%) and (tertiary): cadaveric graft transplantation (15%). Consequently, just 43.7% of the recipients presenting to us with a potential living donor, did finally benefit from these organs. The mortality rate was 8.3% for 43 recipients presenting with a living donor in comparison to 15% for those who did not (321 recipients between May 1995 and November 2001).

CONCLUSIONS

ALDLT can benefit a significant number of recipients on the waiting list (43.7% of those presenting with a donor). The most frequent exclusion criteria concern donor safety, namely, unsuspected chronic liver diseases and unsuspected thrombophilic disorders.

Impact of Wiener filter in determining the left ventricular volume and ejection fraction using thallium-201 gated SPECT

Patient morphology, as well as the acquisition and reconstruction parameters, may influence the evaluation of the left ventricular volume (LVV) and left ventricular ejection fraction (LVEF) using gated single-photon emission computed tomography (SPECT). The purpose of this study was to examine the influence of gender and reconstruction filter on the measurement of LVV and LVEF using 201Tl gated SPECT. Using a static torso phantom, a female shape was created by the addition of two saline solution-filled balloons fixed on the anterior rib cage. The following parameters were similar for all acquisitions: 90 degrees dual-head gamma camera; 32 projections; 64x64 matrix (pixel size=6.77x6.77 mm); two 20% energy windows centred at 70 and 167 keV. The following acquisition times were tested: 1.25, 10, 20, 30 and 40 s per projection, leading to a total of 10 successive acquisitions. The effect of over-sampling was tested by 2.5 post-acquisition zooming. All SPECT images were successively reconstructed using filtered back-projection with Butterworth and Wiener filters. The effect of gender and reconstruction filter was also studied in 30 patients (15 males and 15 females) with a low likelihood of coronary artery disease. LVVs were calculated using QGS software. By multivariate analysis, the following factors influenced the accuracy of phantom measurement using QGS software: zooming (F=49, P<0.0001), phantom shape (F=61, P<0.0001) and filter type (F=240, P<0.0001). LVV was underestimated in the female shape phantom, even when using the Wiener filter. In patients, LVV and LVEF measurements were independently influenced by gender (P<0.0001) and filter (P<0.0001), but not by zooming. In conclusion, it was demonstrated that LVV was significantly decreased in the female shape phantom, suggesting a significant impact of breast interposition. This underestimation was minimized by use of the Wiener filter. In patients, the impact of the Wiener filter on the assessment of LVVs and LVEF was powerful, but independent of gender, and failed to correct the underestimation of LVVs and the overestimation of LVEF in females.

Liver transplantation and transjugular intrahepatic portosystemic shunt

OBJECTIVE

Describe the results of liver transplantation after installing Transjugular Intrahepatic Portosystemic Shunt (TIPS) and compare them with those of a control group in a comparative, longitudinal, retrospective study.

MATERIALS AND METHODS

Between April 1986 and October 2002, we performed 875 liver transplantations. Between January 1996 and October 2002, 26 transplantations were performed on TIPS carriers. This group was compared with a control cohort of 50 randomly selected patients who underwent transplantation in this period (non-TIPS carriers). Both groups were homogeneous with no significant differences between age, sex United Network for Organ Sharing (UNOS) score, Child stage, or etiology.

RESULTS

Actuarial survival rates at 1 and 3 years: TIPS group 96.15% and 89.29% versus control cohort 87.8% and 81%, respectively. In 73.9%, the TIPS was clearly effective; in 88.9%, a postoperative Doppler revealed normal flow. There were no statistically significant differences compared with time on the waiting list for transplant, duration of the operation, ischemia times, intraoperative consumption of hemoderivates, vascular or nonvascular postoperative complications, duration of stay in the intensive care unit, hospital stay, or retransplantation rate.

CONCLUSIONS

In our experience, TIPS insertion does not affect either the intraoperative or postoperative evolution and is not associated with an increased time on the liver transplant waiting list.

Changes in the incidence and severity of recurrent hepatitis C after liver transplantation over 1990-1999

BACKGROUND/AIM

Changes in immunosuppression and other factors may have changed the severity of recurrent hepatitis C during recent years. This study sought to establish the changes in incidence and severity of recurrent hepatitis C, and its association with the changes in acute rejection and induction immunosuppressive therapy between 1990 and 1999.

PATIENTS AND METHODS

Among 213 liver transplants in HCV-infected recipients, 129 grafts were selected for this study: all grafts with severe recurrent hepatitis C (fibrosis 3-4 in Scheuer's score or fibrosing cholestatic hepatitis), and those grafts without severe recurrence with at least 2 years of follow up. Grafts were divided in 5 groups depending on the year of transplantation to compare recurrent hepatitis C-related variables, AR incidence and induction immunosuppression.

RESULTS

Hepatitis-free survival decreased in recent years (p=0.015). The incidence of fibrosing cholestatic hepatitis was higher among 1996-1997 and the 1998-1999 periods (p=0.019). Survival free of severe hepatitis at 1 year follow up was 95% in 1990-1991 and 80% in 1998-1999; however, in the long-term the survival was similar between groups (p=0.933). HCV-related graft survival at 5 years was 93.5% in the 1990-95 period and 82.5% in 1996-99 (p=0.068). Neither AR nor any regimen of induction immunosuppression was associated with changes in the occurrence of recurrent hepatitis C related survival.

CONCLUSIONS

Severity of recurrent hepatitis C and HCV-related graft loss after liver transplantation were higher in the second half of the 1990s; however, there was no association with AR or induction immunosuppression.

Evidence of bilateral temporal lobe involvement in primary progressive aphasia: a SPECT study

Primary progressive aphasia (PPA) is rare. Only limited series have been reported with SPECT or PET. Moreover, in the majority of studies, the left-to-right asymmetry ratio was used, leading to difficulties in right hemisphere analyzes.

METHODS

Twenty-nine patients with clinical criteria of PPA (Mesulam and Weintraub) were included and compared with 12 control subjects. Complete language examination was performed in all patients. SPECT was performed on a double-head gamma camera after intravenous injection of hexamethylpropyleneamine oxime (22 patients and 12 control subjects) or ethylcysteinate dimer (7 patients). Nineteen regions of interest (ROIs) were drawn on each hemisphere in all patients using the Talairach atlas. The perfusion index (PI = cortex-to-cerebellum ratio) was calculated for each ROI. Atrophy was quantified on MRI by consensus of 3 observers in 16 cortical ROIs. ANOVAs were used to compare the PI between (a). patients and control subjects, (b). patients with (n = 15) or without (n = 14) lexicosemantic abnormalities (LS+ vs. LS-) and patients with (n = 19) or without (n = 10) arthric disorders (A+ vs. A-), and (c). patients with or without atrophy.

RESULTS

In the 29 patients, the PI was significantly lower in the left temporopolar, left lateral temporal, left Wernicke, left parietal, and right lateral temporal cortex when compared with control subjects (P < 0.001). In LS+ patients versus control subjects, the PI significantly decreased in the left temporal cortex (lateral temporal; medial temporal; temporopolar; Wernicke), left Broca, left parietal, and right lateral temporal cortex (P < 0.001). In addition, LS+ versus LS- comparison showed a significant decrease in the left lateral, left medial temporal, and left Broca cortex (P < 0.001). In comparison with control subjects, the PI was not significantly different in A+ patients, whereas in A- patients the PI was significantly decreased in the left and right lateral temporal cortex, left Wernicke, and left parietal cortex. Moreover, the PI significantly decreased in the left lateral temporal region in A+ patients compared with A- patients. Finally, in patients without atrophy, the PI significantly decreased in the right and left lateral temporal cortex and the left parietal cortex (P < 0.01).

CONCLUSION

Our study demonstrates that right-handed patients with PPA present a decreased perfusion in the bilateral temporal cortex. Moreover, in these regions, morphologic abnormalities are preceded by perfusion abnormalities. Finally, our results show that large left temporal dysfunction occurs in patients with LS disorders.

[The best of nuclear cardiology and MRI in 2002]

In Nuclear Cardiology, the year 2002 was marked by a great number of studies on the gated-SPECT, which allows joint analysis of left ventricle perfusion and contraction. Even if conventional perfusion tomoscintigraphy confirms its foreground role, notably for prognostic evaluation, the value of the gated-SPECT is particularly significant in all areas of its use: coronary heart disease screening, prognosis evaluation, and myocardial viability assessment. Cavitary tomoscintigraphy allows direct evaluation of the ejection fraction and volumes in both ventricles. This innovative technique has been the subject of a great deal of methodological validation work, and will very likely replace traditional isotopic angiography in the future. At last, the value of MIBG scintigraphy for prognostic evaluation, of cardiac insufficiency has been defined, as has its significance for providing evidence of the effect of betablockers on pre-synaptic sympathetic innervation. The year 2002 has also been very fertile for technological innovations, methodological work, and in clinical studies concerning cardiac MRI. In particular, the significance of MRI for evaluating myocardial viability and the transmural extension of necrosis is now well established. Similarly, MRI is becoming an inescapable element in the assessment of congenital cardiopathy. However, its diffusion on a wider scale will only be possible if there is direct collaboration between cardiologists and radiologists.

Cine-MR Fourier phase imaging for quantification of regional wall asynergy in patients with anterior myocardial infarction

PURPOSE

The aim of this study was to evaluate whether Fourier analysis of cine-MR could detect wall motion abnormalities in patients with myocardial infarction.

METHODS

Ten patients with anterior myocardial infarction (seven men and three women; mean age, 58 +/- 16 years) were compared with six control subjects (four men and two women; mean age, 49 +/- 24 years). Gradient echo cardiac cine-MR slices were transformed using a commercially available Fourier algorithm to obtain phase angles of endocardial segments. Mean phase angle and phase dispersion (i.e., SD around the mean) were calculated. Segmental wall motion was evaluated using a 16-segment model and correlated to Fourier phase analysis.

RESULTS

Mean phase angle and phase dispersion were increased in patients compared with control subjects (respectively, 191 degrees +/- 23 degrees vs. 161 degrees +/- 25 degrees, P < 0.0001 and 21 degrees +/- 10 degrees vs. 11 degrees +/- 8 degrees, P = 0.0007). Analysis of variance showed a significant increased dispersion on basal slices (P = 0.002) mostly due to flow-void and entry slice phenomenon.

CONCLUSIONS

Fourier phase analysis of cardiac cine-MR is feasible and allows the evaluation of ventricular asynergy on the basis of endocardial wall motion.

[Myocardial Infarction in the population aged 25-74 in Navarra. Incidence, lethality and treatment in the period 1997-98. IBERICA study]

The principal aim of this study was to determine the incidence of Myocardial Infarction in the population aged 25-74 in Navarra, lethality after 28 days, and the characteristics of the treatment applied in the hospitals during the years 1997-1998. A search was conducted for possible cases of heart attack in the hospital services responsible for attending to them, by means of a review of clinical histories. The lethal cases that did not reach the hospitals were researched through the statistical bulletins of deaths, with the information on these deaths completed through the family doctors. 1,059 coronary events were registered, which corresponded to a crude rate of attack of 238 cases per 100,000 amongst men and 59 cases per 100,000 amongst women. Amongst the male patients who reached hospital alive, 50% were smokers, 41% showed hypercholesterolaemia, 35.9% were hypertense and 16% were diabetic. Amongst the women, who showed a higher average age, arterial hypertension was the most frequent risk factor, with 66%. During hospitalisation thrombolysis was carried out on 39.2% of the patients, primary or rescue angioplasty on 4.6%; aspirin or other anticoagulants were administered to 94.2%, beta-blockers to 60.6% and IECA to 37.4%. This study has shown that the frequency of Myocardial Infarction in Navarra is lower than that registered in many European and North American countries, and is concordant with the low rates of mortality due to this cause. Global analysis of the data shows that a high implementation of the care guidelines for this disease with respect to the use of efficient therapies could be observed in the years 1997 and 1998. Nonetheless, with the exception of the use of anticoagulants, hospital variability has been observed in the use of thrombolytic therapy and adjuvant therapies such as the beta-blockers or ACE Inhibitor, and in the use of diagnostic techniques such as arteriography.