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OBJECTIVES: The aim of this cross-sectional study was to investigate the association of left atrial (LA) strain parameters with demographics, clinical data, cardiovascular magnetic resonance (CMR) findings, and cardiac complications (heart failure and arrhythmias) in a cohort of patients with ß-thalassemia major (ß-TM). MATERIALS AND METHODS: We considered 264 ß-TM patients (133 females, 36.79 ± 11.95 years) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project. Moreover, we included 35 sex- and age-matched healthy controls (14 females, mean age 37.36 ± 17.52 years). Reservoir, conduit, and booster LA functions were analysed by CMR feature tracking using dedicated software. RESULTS: Compared to the healthy control group, ß-TM patients demonstrated lower LA reservoir strain and booster strains, as well as LA reservoir and booster strain rates. However, no differences were found in LA conduit deformation parameters. In ß-TM patients, ageing, sex, and left ventricle (LV) volume indexes were independent determinants of LA strain parameters. The number of segments with late gadolinium enhancement (LGE) significantly correlated with all LA strain parameters, with the exception of the LA conduit rate. Patients with cardiac complications exhibited significantly impaired strain parameters compared to patients without cardiac complications. CONCLUSION: In patients with ß-TM, LA strain parameters were impaired compared to control subjects, and they exhibited a significant correlation with the number of LV segments with LGE. Furthermore, patients with cardiac complications had impaired left atrial strain parameters. Clinical relevance statement In patients with ß-thalassemia major, left atrial strain parameters were impaired compared to control subjects and emerged as a sensitive marker of cardiac complications, stronger than cardiac iron levels. KEY POINTS: ⢠Compared to healthy subjects, ß-thalassemia major patients demonstrated significantly lower left atrial reservoir strain and booster strains, as well as left atrial reservoir and booster strain rates. ⢠In ß-thalassemia major, ageing, sex, and left ventricular volume indexes were independent determinants of left atrial strain parameters, while left atrial strain parameters were not correlated with myocardial iron overload. ⢠An independent association between reduced left atrial strain parameters and a history of cardiac complications was found in ß-thalassemia major patients.
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We employed an unsupervised clustering method that integrated demographic, clinical, and cardiac magnetic resonance (CMR) data to identify distinct phenogroups (PGs) of patients with beta-thalassemia intermedia (ß-TI). We considered 138 ß-TI patients consecutively enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) Network who underwent MR for the quantification of hepatic and cardiac iron overload (T2* technique), the assessment of biventricular size and function and atrial dimensions (cine images), and the detection of replacement myocardial fibrosis (late gadolinium enhancement technique). Three mutually exclusive phenogroups were identified based on unsupervised hierarchical clustering of principal components: PG1, women; PG2, patients with replacement myocardial fibrosis, increased biventricular volumes and masses, and lower left ventricular ejection fraction; and PG3, men without replacement myocardial fibrosis, but with increased biventricular volumes and masses and lower left ventricular ejection fraction. The hematochemical parameters and the hepatic and cardiac iron levels did not contribute to the PG definition. PG2 exhibited a significantly higher risk of future cardiovascular events (heart failure, arrhythmias, and pulmonary hypertension) than PG1 (hazard ratio-HR = 10.5; p = 0.027) and PG3 (HR = 9.0; p = 0.038). Clustering emerged as a useful tool for risk stratification in TI, enabling the identification of three phenogroups with distinct clinical and prognostic characteristics.
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We assessed the prognostic value of multiparametric cardiovascular magnetic resonance (CMR) in predicting death from heart failure (HF) in thalassemia major (TM). We considered 1398 white TM patients (30.8 ± 8.9 years, 725 women) without a history of HF at baseline CMR, which was performed within the Myocardial Iron Overload in Thalassemia (MIOT) network. Iron overload was quantified by using the T2* technique, and biventricular function was determined with cine images. Late gadolinium enhancement (LGE) images were acquired to detect replacement myocardial fibrosis. During a mean follow-up of 4.83 ± 2.05 years, 49.1% of the patients changed the chelation regimen at least once; these patients were more likely to have significant myocardial iron overload (MIO) than patients who maintained the same regimen. Twelve (1.0%) patients died from HF. Significant MIO, ventricular dysfunction, ventricular dilation, and replacement myocardial fibrosis were identified as significant univariate prognosticators. Based on the presence of the four CMR predictors of HF death, patients were divided into three subgroups. Patients having all four markers had a significantly higher risk of dying for HF than patients without markers (hazard ratio (HR) = 89.93; 95%CI = 5.62-1439.46; p = 0.001) or with one to three CMR markers (HR = 12.69; 95%CI = 1.60-100.36; p = 0.016). Our findings promote the exploitation of the multiparametric potential of CMR, including LGE, for better risk stratification for TM patients.
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The aim of this multicenter study was to prospectively assess the predictive value of multiparametric cardiac magnetic resonance (CMR) for cardiovascular complications in sickle cell disease (SCD) patients. Among all patients with hemoglobinopathies consecutively enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) Network, we selected 102 SCD patients (34.38 ± 12.67 years, 49 females). Myocardial iron overload (MIO) was measured by the multislice multiecho T2* technique. Atrial dimensions and biventricular function parameters were quantified by cine images. Late gadolinium enhancement (LGE) images were acquired to detect focal myocardial fibrosis. At baseline CMR, only two patients had significant MIO (global heart T2* < 20 ms). During a mean follow-up of 63.01 ± 24.95 months, 11 cardiovascular events (10.8%) were registered: 3 pulmonary hypertension, 2 supraventricular arrhythmias, 1 heart failure, 1 death for heart failure, 1 pulmonary embolism, 1 peripheral vascular disease, 1 transient ischemic attack, and 1 death after acute chest syndrome. In the multivariate analysis, the independent CMR predictors of cardiovascular events were left ventricular (LV) ejection fraction (hazard ratio-HR = 0.88; p = 0.025) and right ventricular (RV) mass index (HR = 1.09; p = 0.047). According to the receiver-operating characteristic curve analysis for adverse events, an LV ejection fraction < 58.9% and an RV mass index > 31 g/m2 were optimal cut-off values. Reduced left ventricular ejection fraction and increased right ventricular mass index showed a significant prognostic value in patients with SCD. Our data seem to suggest that CMR may be added as a screening tool for identifying SCD patients at high risk for cardiopulmonary and vascular diseases.
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Anemia de Células Falciformes , Cardiopatías , Insuficiencia Cardíaca , Sobrecarga de Hierro , Femenino , Humanos , Pronóstico , Volumen Sistólico , Medios de Contraste , Función Ventricular Izquierda , Imagen por Resonancia Cinemagnética/métodos , Gadolinio , Fibrosis , Espectroscopía de Resonancia Magnética , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/diagnóstico por imagen , Sobrecarga de Hierro/diagnóstico por imagen , Sobrecarga de Hierro/etiología , Valor Predictivo de las PruebasRESUMEN
We longitudinally evaluated the effects of regular blood transfusions (BTs), in the real-life context of the Myocardial Iron Overload in Thalassaemia network, in patients with thalassaemia intermedia (TI). We considered 88 patients with TI (52 females) who started regular BTs after the age of 18 years. Magnetic resonance imaging was used to quantify iron overload and biventricular function. For 56·8% of the patients there were more than two indications for the transition to regular BTs, with anaemia present in 94·0% of the cases. A significant decrease in nucleated red blood cells, platelets, lactate dehydrogenase, bilirubin, and uric acid levels was detected 6 months after starting regular BTs. After the transition to the regular BT regimen there was a significant increase only in the frequency of hypothyroidism and osteopenia, and a significant decrease in liver iron and cardiac index. The percentage of chelated patients increased significantly after starting regular BTs. The decision to regularly transfuse patients with TI may represent a way to prevent or slow down the natural progression of the disease, despite the more complex initial management.
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Transfusión Sanguínea , Imagen por Resonancia Magnética , Talasemia beta , Adolescente , Adulto , Anciano , Bilirrubina/sangre , Plaquetas/metabolismo , Enfermedades Óseas Metabólicas/sangre , Enfermedades Óseas Metabólicas/etiología , Niño , Eritroblastos/metabolismo , Femenino , Estudios de Seguimiento , Humanos , Hipotiroidismo/sangre , Hipotiroidismo/etiología , L-Lactato Deshidrogenasa/sangre , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Ácido Úrico/sangre , Talasemia beta/sangre , Talasemia beta/diagnóstico por imagen , Talasemia beta/terapiaRESUMEN
OBJECTIVES: To assess the transferability of the magnetic resonance imaging (MRI) multislice multiecho T2* technique for pancreatic iron overload assessment. METHODS: Multiecho T2* sequences were installed on ten 1.5-T MRI scanners of the three main vendors. Five healthy subjects (n = 50) were scanned at each site. Five patients with thalassemia (n = 45) were scanned locally at each site and were rescanned at the reference site within 1 month. T2* images were analyzed using a previously validated software and the global pancreatic T2* value was calculated as the mean of T2* values over the head, body, and tail. RESULTS: T2* values of healthy subjects were above 26 ms and showed inter-site homogeneity. The T2* values measured in the MRI sites were comparable to the correspondent values observed in the reference site (12.02 ± 10.20 ms vs 11.98 ± 10.47 ms; p = 0.808), and the correlation coefficient was 0.978 (p < 0.0001). Coefficients of variation (CoVs) ranged from 4.22 to 9.77%, and the CoV for all the T2* values independently from the sites was 8.55%. The intraclass correlation coefficient (ICC) for each MRI site was always excellent and the global ICC was 0.995, independently from the sites. The mean absolute difference in patients with pancreatic iron (n = 39) was -0.15 ± 1.38 ms. CONCLUSION: The gradient-echo T2* MRI technique is an accurate and reproducible means for the quantification of pancreatic iron and may be transferred among MRI scanners by different vendors in several centers. KEY POINTS: ⢠The gradient-echo T2* MRI technique is an accurate and reproducible means for the quantification of pancreatic iron. ⢠The gradient-echo T2* MRI technique for the quantification of pancreatic iron may be transferred among MRI scanners by different vendors in several centers. ⢠Pancreatic iron might serve as an early predictor of cardiac siderosis and is the strongest overall predictor of glucose dysregulation.
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Hierro/metabolismo , Imagen por Resonancia Magnética/métodos , Páncreas/patología , Siderosis/diagnóstico , Adulto , Femenino , Humanos , Masculino , Páncreas/metabolismo , Reproducibilidad de los Resultados , Siderosis/metabolismoRESUMEN
AIM: to evaluate the relationship between uric acid (UA), hepatic and cardiac iron overload (T2*-MRI), ferritin, endocrinological diseases and cardiac complications in a large thalassemia major (TM) cohort. METHODS: A total of 369 TM patients (187 men; 33 ± 6 years) were retrospectively studied, from the myocardial iron overload in thalassemia (MIOT) electronic databank. RESULTS: Multiple regression model identified male sex (p < 0.001), BMI (p < 0.001) and T2* (p ≤ 0.001) as UA independent correlates. Moreover, UA and derivatives of reactive oxygen species (an oxidative index; r = -0.3; p ≤ 0.05) are inversely correlated. Conversely, the multivariate logistic analysis identified low UA (NANHES-III criteria) as one independent predictor for low global heart T2* (p < 0.5) together with liver iron concentrations (>3 mg/g/dw), heart failure, endocrinopathies, ferritin (>2000 ng/l), alanine transaminase (>40 UI/l) and/or aspartate transaminase (>35 UI/l) and/or glutamyl transferase (>64 UI/l). DISCUSSION: UA appears directly associated to T2* and inversely with derivatives of reactive oxygen species, and as such reduced according to increased oxidative stress and cardiac iron overload in TM patients.
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Miocardio/metabolismo , Ácido Úrico/sangre , Talasemia beta/sangre , Adulto , Estudios de Cohortes , Femenino , Ferritinas/sangre , Humanos , Hierro/metabolismo , Hígado/metabolismo , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Talasemia beta/diagnóstico por imagen , Talasemia beta/metabolismoRESUMEN
OBJECTIVES: The liver remains the primary site of iron storage, with liver iron concentration (LIC) being a strong surrogate of total body iron. MRI-R2 can accurately measure LIC. The LICNET (Liver Iron Cutino Network) was established to diagnostics of liver iron overload by MRI-R2 subjects with hemochromatosis in hematological disorders. The aims of the study were to look at variation in LIC measurements during time across different chelation regimens. METHODS: This was a cross-sectional study of 130 patients attending 9 Italian centers participating in the LICNET. LIC comparisons over time (T0 and T1 ) were made using t test and/or Wilcoxon test. RESULTS: LIC significantly decreased from MRI1 to MRI2 although at high variance (median change -0.8 mg Fe/g dw, range: -29.0 to 33.0; P = .011) and 7.7% of patients shifted from LIC values of high risk (>15 mg Fe/g dw) to an intermediate-risk category (7-15 mg Fe/g dw). Median change in LIC and correlation with serum ferritin levels (SF), during different chelation regimens, is reported. CONCLUSIONS: These findings suggest as longitudinal variation in the LIC is possible, across all chelation regimens. It confirms as SF levels not always can be used for estimating changes in LIC.
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Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/patología , Hierro/metabolismo , Hígado/metabolismo , Hígado/patología , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Terapia por Quelación , Niño , Estudios Transversales , Femenino , Ferritinas/sangre , Humanos , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/diagnóstico por imagen , Sobrecarga de Hierro/etiología , Hígado/diagnóstico por imagen , Hígado/efectos de los fármacos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
In the last few decades, the life expectancy of regularly transfused ß-thalassaemia major (TM) patients has dramatically improved following the introduction of safe transfusion practices, iron chelation therapy, aggressive treatment of infections and improved management of cardiac complications. How such changes, especially those attributed to the introduction of iron chelation therapy, improved the survival of TM patients to approach those with ß-thalassaemia intermedia (TI) remains unknown. Three hundred and seventy-nine patients with TM (n = 284, dead 40) and TI (n = 95, dead 13) were followed retrospectively since birth until 30 June 2015 or death. Kaplan-Meir curves showed statistically significant differences in TM and TI survival (P < 0·0001) before the introduction of iron chelation in 1965, which were no longer apparent after that date (P = 0·086), reducing the Hazard Ratio of death in TM compared to TI from 6·8 [95% confidence interval (CI) 2·6-17·5] before 1965 to 2·8 (95% CI 0·8-9·2). These findings suggest that, in the era of iron chelation therapy and improved survival for TM, the major-intermedia dichotomy needs to be revisited alongside future directions in general management and prevention for both conditions.
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Esperanza de Vida , Talasemia beta/clasificación , Talasemia beta/mortalidad , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven , Talasemia beta/epidemiología , Talasemia beta/terapiaRESUMEN
BACKGROUND: Beyond hemoglobin (Hb) levels and performance status, further surrogate markers of appropriate transfusion management should improve the quality of thalassemia care. We investigated the levels of peripheral circulating CD34+ stem cells as an independent marker of appropriate hematopoietic balance in patients with thalassemia. STUDY DESIGN AND METHODS: Peripheral circulating CD34+ stem cells, colony-forming unitgranulocyte, erythrocyte, macrophage, magakaryocyte (CF-GEMM), colony-forming unitgranulocyte/macrophage (CFU-GM), and erythroidburst-forming units (BFU-E) were assayed, according to standard procedures. Patients with thalassemia major (TM) and thalassemia intermedia (TI) were tested and compared to healthy controls. Demographic and clinical data were recorded. RESULTS: Overall, 56 patients with TM (median age, 35 years; range, 13-52 years) and 13 with TI (median age, 44 years; range, 27-67 years) were evaluated. Annual red blood cell (RBC) transfusion requirements ranged from 10 to 65 units in all patients except four nontransfused cases. A significant increase in peripheral circulating stem cells was observed in patients, in comparison with healthy controls. Nontransfused patients showed the mean highest levels of stem cells (CD34, 32.5 ± 14.8/µL; BFU-E, 41.3 ± 22.8/mL; CFU-GM, 19.6 ± 5.6/mL; CFU-GEMM, 9.0 ± 6.1/mL). CD34+ cell count was 6.9 ± 4.5/µL in TM (p = 0.014) and 11.8 ± 14.8/µL (p = 0.051) in TI. Furthermore, only in patients with TI was a significant increase in CFU-GEMM (3.0 ± 4.8 vs. 0.75 ± 2.05/mL, p = 0.0001) observed. At multivariate analysis, peripheral circulating CD34+ stem cells did not correlate with age, sex, smoking habit, number of RBCs units transfused, Hb levels, iron chelation therapy, history of splenectomy, and hypothyroidism. CONCLUSION: Circulating peripheral CD34 + stem cells are increased in ß-thalassemia, in particular in nontransfused patients, compared to healthy controls.
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Biomarcadores/sangre , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/patología , Talasemia beta/sangre , Talasemia beta/diagnóstico , Talasemia beta/terapia , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Pronóstico , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Real-life data on the use of R2 MRI for the assessment of liver iron concentration (LIC) remain limited. METHODS: We conducted a cross-sectional analysis on 363 patients (mean age 35.6 yr, 44.1% men) with hemoglobinopathies (204 ß-thalassemia major [TM], 102 ß-thalassemia intermedia [TI], and 57 sickle cell disease [SCD]) that were evaluated with R2 MRI as part of LICNET, an MRI network of 13 Italian treatment centers. RESULTS: The mean LIC was 7.8 mg/g (median: 4.0), with high LIC (>7 mg/g) noted in both transfused (TM, TI 37%; SCD 38%) and non-transfused (TI 20%) patients. Ferritin levels correlated with LIC in both transfused (TM, TI, SCD) and non-transfused (TI) patients (P < 0.001), although lower values predicted high LIC in non-transfused patients (1900 vs. 650 ng/mL in TM vs. non-transfused TI). A correlation between LIC and ALT levels was only noted in HCV-negative patients (rs = 0.316, P < 0.001). The proportion of patients with high LIC was significantly different between iron chelators used (P = 0.023), with the lowest proportion in deferasirox (30%) and highest in deferiprone (53%)-treated patients. CONCLUSIONS: High LIC values persist in subgroups of patients with hemoglobinopathy, warranting closer monitoring and management optimization, even for non-transfused patients with relatively low ferritin levels.
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Hemoglobinopatías/complicaciones , Sobrecarga de Hierro/diagnóstico , Sobrecarga de Hierro/etiología , Hierro/metabolismo , Hígado/metabolismo , Hígado/patología , Imagen por Resonancia Magnética , Adolescente , Adulto , Anciano , Alanina Transaminasa/sangre , Biomarcadores , Niño , Comorbilidad , Estudios Transversales , Femenino , Ferritinas/sangre , Hemoglobinopatías/diagnóstico , Humanos , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/tratamiento farmacológico , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
The aim of this study was to evaluate, in a large cohort of chronically transfused patients, whether the presence of extramedullary hematopoiesis (EMH) accounts for the typical patterns of cardiac iron distribution and/or cardiac function parameters. We retrospectively selected 1,266 thalassemia major patients who had undergone regular transfusions (611 men and 655 women; mean age: 31.3 ± 8.9 years, range: 4.2-66.6 years) and were consecutively enrolled within the Myocardial Iron Overload in Thalassemia network. The presence of EMH was evaluated based on steady-state free precession sequences; cardiac and liver iron overloads were quantified using a multiecho T2* approach; cardiac function parameters and pulmonary diameter were quantified using the steady-state free precession sequences; and myocardial fibrosis was evaluated using the late gadolinium enhancement technique. EMH was detected in 167 (13.2%) patients. The EMH+ patients had significantly lower cardiac iron overload than that of the EMH- patients (P = 0.003). The patterns of cardiac iron distribution were significantly different in the EMH+ and EMH- patients (P < 0.0001), with a higher prevalence of patients with no myocardial iron overload and heterogeneous myocardial iron overload and no significant global heart iron in the EMH+ group EMH+ patients had a significantly higher left ventricle mass index (P = 0.001) and a significantly higher pulmonary artery diameter (P = 0.002). In conclusion, in regularly transfused thalassemia patients, EMH was common and was associated with a thalassemia intermedia-like pattern of cardiac iron deposition despite regular transfusion therapy.
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Hematopoyesis Extramedular , Sobrecarga de Hierro/metabolismo , Hierro/metabolismo , Miocardio/metabolismo , Reacción a la Transfusión , Talasemia beta/metabolismo , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios Transversales , Femenino , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/patología , Humanos , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/patología , Hígado/metabolismo , Hígado/patología , Masculino , Persona de Mediana Edad , Miocardio/patología , Estudios Retrospectivos , Talasemia beta/patología , Talasemia beta/terapiaRESUMEN
In patients with thalassemia intermedia (TI), such as beta-TI, alpha-thalassemia (mainly HbH disease and mild/moderate forms of HbE/beta-thalassemia), iron overload is an important challenge in terms of diagnosis, monitoring, and treatment. Moreover, to date, the only possible chelators available are deferoxamine, deferasirox, and deferiprone. Here, we report the first 5-year long-term randomized clinical trial comparing the effectiveness of deferiprone versus deferoxamine in patients with TI. Body iron burden, which was determined by measuring serum ferritin levels in the same patient over 5 years and analyzed according to the generalized linear mixed model (GLMM), showed a linear decrease over time in the mean serum ferritin levels in both treatment groups (P-value = 0.035). The overall period of observation was 235.2 person-years for the deferiprone patients compared with 214.3 person-years for the deferoxamine patients. The results of the log-rank test suggested that the deferiprone treatment did not affect survival compared with the deferoxamine treatment (P-value = 0.360). The major adverse events observed included gastrointestinal symptoms and joint pain or arthralgia. Neutropenia and agranulocytosis were also detected, suggesting needing of strict hematological control. In conclusion, long-term iron chelation therapy with deferiprone is associated with an efficacy and safety similar to that of deferoxamine, suggesting that this drug is an alternative option in cases in which deferoxamine and deferasirox are contraindicated.
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Deferoxamina/administración & dosificación , Quelantes del Hierro/administración & dosificación , Sobrecarga de Hierro/terapia , Piridonas/administración & dosificación , Talasemia beta/terapia , Adulto , Agranulocitosis/inducido químicamente , Agranulocitosis/fisiopatología , Artralgia/inducido químicamente , Artralgia/fisiopatología , Terapia por Quelación/métodos , Deferiprona , Deferoxamina/efectos adversos , Femenino , Ferritinas/metabolismo , Humanos , Quelantes del Hierro/efectos adversos , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/mortalidad , Modelos Lineales , Masculino , Persona de Mediana Edad , Neutropenia/inducido químicamente , Neutropenia/fisiopatología , Piridonas/efectos adversos , Análisis de Supervivencia , Reacción a la Transfusión , Talasemia beta/metabolismo , Talasemia beta/mortalidad , Talasemia beta/patologíaRESUMEN
T2* maps obtained by the processing of multiecho MR sequences can be useful in several clinical applications. T2* map generation procedures should join a processing time compatible with on-line image analysis with a good precision in the entire T2* range of clinical interest. Fast generation of T2* maps can be achieved by the estimation of the T2* values by the weighted linear fitting of the logarithm of the signal (WLSL) method. This approach fails if the signal decay diverges from a pure exponential decay, as happens at low T2* values where the rapid decay in the signal intensity leads to a plateau in the later echo times (TE). The proposed method implements the automatic truncation of the signal decay curves to be fitted in order to compensate for the signal collapse at low T2* values, allowing the extension of the WLSL method through the entire clinical range of T2* values. Validation was performed on synthetic images and on 60 thalassemia major patients with different levels of myocardial iron overload. Phantom experiments showed that a 5% fitting error threshold represented the best compromise between T2* value measurement precision and processing time. A good agreement was found between T2* map pixel-wise measurements and ROI-based measurements performed by expert readers (CoV=1.84% in global heart T2*, CoV=5.8% in segmental analysis). In conclusion, the developed procedure was effective in generating correct T2* maps for the entire T2* clinical range.
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Procesamiento de Imagen Asistido por Computador/métodos , Sobrecarga de Hierro , Imagen por Resonancia Magnética/métodos , Miocardio , Talasemia beta , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/instrumentación , Sobrecarga de Hierro/diagnóstico por imagen , Sobrecarga de Hierro/metabolismo , Imagen por Resonancia Magnética/instrumentación , Masculino , Miocardio/metabolismo , Miocardio/patología , Fantasmas de Imagen , Radiografía , Talasemia beta/diagnóstico por imagen , Talasemia beta/metabolismoRESUMEN
The relationship between diabetes mellitus (DM) and cardiac complications has never been systematically studied in thalassaemia major (TM). We evaluated a large retrospective historical cohort of TM to determine whether DM is associated with a higher risk of heart complications. We compared 86 TM patients affected by DM with 709 TM patients without DM consecutively included in the Myocardial Iron Overload in Thalassaemia database where clinical/instrumental data are recorded from birth to the first cardiovascular magnetic resonance (CMR) exam. All of the cardiac events considered were developed after the DM diagnosis. In DM patients versus non-DM patients we found a significantly higher frequency of cardiac complications (46.5% vs. 16.9%, P < 0.0001), heart failure (HF) (30.2% vs. 11.7%, P < 0.0001), hyperkinetic arrhythmias (18.6% vs. 5.5%, P < 0.0001) and myocardial fibrosis assessed by late gadolinium enhancement (29.9% vs. 18.4%, P = 0.008). TM patients with DM had a significantly higher risk of cardiac complications [odds ratio (OR) 2.84, P < 0.0001], HF (OR 2.32, P = 0.003), hyperkinetic arrhythmias (OR 2.21, P = 0.023) and myocardial fibrosis (OR 1.91, P = 0.021), also adjusting for the absence of myocardial iron overload assessed by T2* CMR and for the covariates (age and/or endocrine co-morbidity). In conclusion, DM significantly increases the risk for cardiac complications, HF, hyperkinetic arrhythmias and myocardial fibrosis in TM patients.
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Diabetes Mellitus/metabolismo , Cardiomiopatías Diabéticas/complicaciones , Cardiopatías/complicaciones , Sobrecarga de Hierro/complicaciones , Talasemia beta/complicaciones , Adulto , Estudios de Cohortes , Diabetes Mellitus/patología , Cardiomiopatías Diabéticas/metabolismo , Femenino , Cardiopatías/metabolismo , Cardiopatías/patología , Humanos , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/patología , Masculino , Estudios Retrospectivos , Talasemia beta/diagnóstico , Talasemia beta/metabolismo , Talasemia beta/patologíaRESUMEN
Transfusion and iron chelation treatment have significantly reduced morbidity and improved survival of patients with thalassemia major. However, cardiac disease continues to be the most common cause of death. We report the left-ventricular ejection fraction, determined by echocardiography, in one hundred sixty-eight patients with thalassemia major followed for at least 5years who received continuous monotherapy with deferoxamine (N=108) or deferiprone (N=60). The statistical analysis, using the generalized estimating equations model, indicated that the group treated with deferiprone had a significantly better left-ventricular ejection fraction than did those treated with deferoxamine (coefficient 0.97; 95% CI 0.37; 1.6, p=0.002). The heart may be particularly sensitive to iron-induced mitochondrial damage because of the large number of mitochondria and its low level of antioxidants. Deferiprone, because of its lower molecular weight, might cross into heart mitochondria more efficiently, improving their activity and, thereby, myocardial cell function. Our findings indicate that the long-term administration of deferiprone significantly enhances left-ventricular function over time in comparison with deferoxamine treatment. However, because of limitations related to the design of this study, these findings should be confirmed in a prospective, randomized clinical trial.
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Deferoxamina/uso terapéutico , Cardiopatías/etiología , Cardiopatías/fisiopatología , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/etiología , Piridonas/uso terapéutico , Volumen Sistólico/efectos de los fármacos , Talasemia beta/complicaciones , Adulto , Deferiprona , Femenino , Cardiopatías/tratamiento farmacológico , Humanos , Quelantes del Hierro/uso terapéutico , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Función Ventricular Izquierda/efectos de los fármacos , Adulto JovenRESUMEN
Cardiac damage remains a major cause of mortality among patients with thalassemia major. The detection of a lower cardiac magnetic resonance T2* (CMR-T2*) signal has been suggested as a powerful predictor of the subsequent development of heart failure. However, the lack of worldwide availability of CMR-T2* facilities prevents its widespread use for follow-up evaluations of cardiac function in thalassemia major patients, warranting the need to assess the utility of other possible procedures. In this setting, the determination of left ventricular ejection fraction (LVEF) offers an accurate and reproducible method for heart function evaluation. These findings suggest a reduction in LVEF≥7%, over time, determined by 2-D echocardiography, may be considered a strong predictive tool for the detection of thalassemia major patients with increased risk of cardiac death. The reduction of LVEF≥7% had higher (84.76%) predictive value. Finally, Kaplan-Meier survival curves of thalassemia major patients with LVEF≥7% showed a statistically significant decreased probability of survival for heart disease (p=0.0022). However, because of limitations related to the study design, such findings should be confirmed in a large long-term prospective clinical trial.
Asunto(s)
Muerte Súbita Cardíaca/etiología , Ecocardiografía , Volumen Sistólico , Talasemia beta/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Modelos Estadísticos , Curva ROC , Adulto Joven , Talasemia beta/complicaciones , Talasemia beta/fisiopatologíaRESUMEN
A multicenter randomized open-label long-term sequential deferipronedeferoxamine (DFP-DFO) versus DFP alone trial (sequential DFP-DFO) performed in patients with thalassemia major (TM) was retrospectively reanalyzed to assess the variation in the left ventricular ejection fraction (LVEF) [1].
Asunto(s)
Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/fisiopatología , Quelantes del Hierro/efectos adversos , Piridonas/uso terapéutico , Talasemia beta/tratamiento farmacológico , Talasemia beta/fisiopatología , Adulto , Deferiprona , Deferoxamina/administración & dosificación , Deferoxamina/uso terapéutico , Esquema de Medicación , Quimioterapia Combinada , Femenino , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Quelantes del Hierro/administración & dosificación , Masculino , Modelos Biológicos , Piridonas/administración & dosificación , Estudios Retrospectivos , Volumen Sistólico/efectos de los fármacos , Factores de Tiempo , UltrasonografíaRESUMEN
This study aimed to determine the feasibility, reproducibility, and reliability of the multiecho T*(2) Magnetic resonance imaging technique at 3 T for myocardial and liver iron burden quantification and the relationship between T*(2) values at 3 and 1.5 T. Thirty-eight transfusion-dependent patients and 20 healthy subjects were studied. Cardiac segmental and global T*(2) values were calculated after developing a correction map to compensate the artifactual T*(2) variations. The hepatic T*(2) value was determined over a region of interest. The intraoperator and interoperator reproducibility for T*(2) measurements at 3 T was good. A linear relationship was found between patients' R *2 (1000/T*(2) ) values at 3 and 1.5 T. Segmental correction factors were significantly higher at 3 T. A conversion formula returning T*(2) values at 1.5 T from values at 3 T was proposed. A good diagnostic reliability for T*(2) assessment at 3 T was demonstrated. Lower limits of normal for 3 T T*(2) values were 23.3 ms, 21.1 ms, and 11.7 ms, for the global heart, mid-ventricular septum, and liver, respectively. In conclusion, T*(2) quantification of iron burden in the mid-ventricular septum, global heart, and no heavy-moderate livers resulted to be feasible, reproducible, and reliable at 3 T. Segmental heart T*(2) analysis at 3 T may be challenging due to significantly higher susceptibility artifacts.
Asunto(s)
Aumento de la Imagen/métodos , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/patología , Imagen por Resonancia Magnética/métodos , Talasemia/complicaciones , Talasemia/patología , Adulto , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Polymorphisms in the interleukin-28B are important determinants in the spontaneous and drug-induced control of hepatitis C virus infection. DESIGN AND METHODS: We assessed the association of rs8099917 and rs12979860 polymorphisms with spontaneous viral clearance, severity of liver fibrosis, and response to interferon-monotherapy in 245 thalassemia major patients with hepatitis C virus infection. RESULTS: Ninety-eight patients (40%) had a spontaneous viral clearance while 147 patients (60%) developed a chronic infection. Spontaneous viral clearance was more frequent among patients with the T/T genotype of rs8099917 polymorphism (OR 2.130; P = 0.008) or C/C genotype of rs12979860 polymorphism (OR 2.425; P = 0.001). During observation, 131 patients with chronic infection underwent a liver biopsy; age (OR 1.058; P = 0.01) G/T or G/G genotypes of rs8099917 polymorphism (OR 3.962; P = 0.001), and C/T or T/T genotypes of rs12979860 polymorphism (OR 3.494; P = 0.005) were associated with severe liver fibrosis, independent of liver iron concentration. Finally, T/T genotype of rs8099917 polymorphism (OR 3.014; P = 0.03) or C/C genotype of rs12979860 polymorphism (OR 3.285; P = 0.01), age (OR 0.902; P = 0.001), female gender (OR 3.418; P = 0.01) and 2 or 3 virus C genotypes (OR 4.700; P=0.007) were independently associated with sustained virological response in 114 patients treated with alpha-interferon. Conclusions Polymorphisms in the interleukin-28B are associated with the control of hepatitis C virus infection in thalassemia major patients, and understanding allelic patterns has an important role in determining prognosis and therapeutic management.