Comparative study on iron content detection by energy spectral CT and MRI in MDS patients.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e19032-e19032
Author(s):  
Yao Zhang ◽  
Chao Xiao ◽  
Jing Li ◽  
Lu-Xi Song ◽  
You-Shan Zhao ◽  
...  
Keyword(s):  
Iron Overload ◽  
Iron Content ◽  
Detection Rate ◽  
Iron Concentration ◽  
High Iron Content ◽  
Liver Iron ◽  
Detection Rates ◽  
Cardiac Iron ◽  
Advantages And Disadvantages ◽  
The Difference

e19032 Background: Myelodysplastic syndrome(MDS) patients may have iron overload due to long-term RBC transfusion or combined with abnormal iron metabolism.what are the differences of iron content detection by magnetic resonance imaging (MRI) and dual energy spectrum computed tomography (DECT)? What are the advantages and disadvantages of the two methods in the state of high and low iron deposition? Can the two methods complement each other? The purpose of this study was to compare the difference of liver/cardiac iron content detection in MDS patients by DECT and MRI under different adjust serum ferritin (ASF) levels. Methods: Liver and cardiac iron content were detected by DECT and MRI. Patients divided into different subgroups according to ASF. Compared the detection rate between DECT and MRI group, and correlation between liver/cardiac iron content detected by DECT/MRI and ASF in each subgroups. Results: The detection rate of iron overload(IO) in DECT group was lower than that of MRI group with ASF < 1000ng/ml subgroup,DECT and MRI had similar detection rates of moderate to severe IO with 1000≤ ASF < 5000ng/ml subgroup, detection rate of severe IO in MRI was lower than that of DECT with 5000ng/ml ≤ ASF subgroup. In patients underwent DECT and MRI examination at the same time, ASF was significantly correlated with hepatic VIC but not with liver iron concentration (LIC), and LIC correlated with ASF after removed these data of ASF > 5000 mg/L. LIC expression are not significantly different among 1000≤ ASF < 5000ng/ml and 5000 ng/ml ≤ASF subgroup. LIC and liver virtual iron content (VIC) were all significant correlation with ASF when ASF < 2500ng/ml, liver VIC was still correlation with ASF but LIC was not when 2500ng/ml≤ ASF. Neither cardiac VIC nor myocardial iron content (MIC) correlation with ASF in these subgroups. Conclusions: This study showed that MRI and DECT can be used complementary to each other. In high iron content, such as ASF ≥5000ng/ml, DECT detection is more reliable. In patients with low iron content, such as SF < 1000 ng/ml, MRI detection is more reliable. According to ASF, the appropriate detection method can be selected to evaluate the iron content more accurately.

scholarly journals Comparative Study on Iron Content Detection by Energy Spectral CT and MRI in MDS Patients

2021 ◽  
Vol 11 ◽  
Author(s):  
Yao Zhang ◽  
Chao Xiao ◽  
Jing Li ◽  
Lu-xi Song ◽  
You-shan Zhao ◽  
...  
Keyword(s):  
Iron Content ◽  
Characteristic Curve ◽  
Iron Concentration ◽  
Roc Curves ◽  
High Iron Content ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Significant Difference ◽  
Spectral Computed Tomography ◽  
The Difference

Objective: The purpose of this study was to identify the difference between dual energy spectral computed tomography (DECT) and magnetic resonance imaging (MRI) used to detect liver/cardiac iron content in Myelodysplastic syndrome (MDS) patients with differently adjusted serum ferritin (ASF) levels.Method: Liver and cardiac iron content were detected by DECT and MRI. Patients were divided into different subgroups according to the level of ASF. The receiver operating characteristic curve (ROC) analysis was applied in each subgroup. The correlation between iron content detected by DECT/MRI and ASF was analyzed in each subgroup.Result: ROC curves showed that liver virtual iron content (LVIC) Az was significantly less than liver iron concentration (LIC) Az in the subgroup with ASF &lt; 1,000 ng/ml. There was no significant difference between LVIC Az and LIC Az in the subgroup with 1,000 ≤ ASF &lt; 2,500 ng/ml and 2,500 ≤ ASF &lt; 5,000 ng/ml. LVIC Az was significantly higher than LIC Az in the subgroup with ASF &lt;5,000 and 5,000 ≤ ASF ng/ml. In patients undergoing DECT and MRI examination on the same day, ASF was significantly correlated with LVIC, whereas no significant correlation was observed between ASF and LIC. After removing the data of ASF &gt; 5,000 mg/L in LIC, LIC became correlated with ASF. There was no significant difference between the subgroup with 2,500 ≤ ASF &lt; 5,000 ng/ml and 5,000 ng/ml ≤ ASF in LIC expression. Furthermore, both LIC and liver VIC had significant correlations with ASF in patients with ASF &lt; 2,500 ng/ml, while LVIC was still correlated with ASF, LIC was not correlated with ASF in patients with 2,500 ng/ml ≤ ASF. Moreover, neither cardiac VIC nor myocardial iron content (MIC) were correlated with ASF in these subgroups.Conclusion: MRI and DECT were complementary to each other in liver iron detection. In MDS patients with high iron content, such as ASF ≥ 5,000 ng/ml, DECT was more reliable than the MRI in the assessment of iron content. But in patients with low iron content, such as ASF &lt; 1,000 ng/ml, MRI is more reliable than DECT. Therefore, for the sake of more accurately evaluating the iron content, the appropriate detection method can be selected according to ASF.

Randomized Controlled Trial of the Efficacy and Safety of Deferiprone in Iron-Overloaded Patients with Sickle Cell Disease or Other Anemias

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 618-618
Author(s):  
Janet L. Kwiatkowski ◽  
Mohsen Saleh Elalfy ◽  
Caroline Fradette ◽  
Mona Hamdy ◽  
Amal El-Beshlawy ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Iron Overload ◽  
Research Funding ◽  
Iron Concentration ◽  
Advisory Committees ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Upper Limit ◽  
Iron Load ◽  
The Difference

Background: Patients with sickle cell disease (SCD) or other rare anemias whose care includes chronic blood transfusions must receive iron chelation to prevent the morbidity of iron overload. Currently, only deferoxamine (DFO) and deferasirox (DFX) are approved chelators in these patient populations. This randomized open-label trial evaluated if the efficacy of deferiprone (DFP) was non-inferior to DFO. DFO was used as the comparator product since DFX was not approved as first-line treatment for SCD at trial initiation. Methods: Participants at 27 sites in 8 countries were randomized in a 2:1 ratio to receive either DFP or DFO for up to 12 months. Those with lower transfusional iron input and/or less severe iron load were prescribed either DFP 25 mg/kg of body weight t.i.d. or DFO 20 mg/kg (children) or 40 mg/kg (adults); those with higher iron input and/or more severe iron load received either DFP 33 mg/kg t.i.d. or DFO up to 40 mg/kg (children) or 50 mg/kg (adults). Dosages could be adjusted over the course of the trial if necessary. Efficacy endpoints were the changes from baseline in liver iron concentration (LIC), cardiac iron, and serum ferritin (SF) at Month 12. The primary endpoint was based on LIC, and for the demonstration of non-inferiority of DFP to DFO, the upper limit of the 95% confidence interval for the difference between treatments had to be no more than 2 mg/g dry weight (dw). All patients had their neutrophil count monitored weekly, whereas other safety assessments and compliance with study therapy were evaluated monthly. Acceptable compliance was defined as taking 80% to 120% of the prescribed dosage. Results: A total of 228 of the targeted 300 patients were dosed with 152 receiving DFP and 76 receiving DFO, to assess non-inferiority. There were no significant differences between the groups in any demographic measures: in each treatment group, 84% of patients had SCD and the remainder had other, rarer forms of transfusion-dependent anemia. Mean age at enrollment was 16.9 years (± 9.6); 53.1% of patients were male; and 77.2% were white, 16.2% black, and 6.6% multi-racial. Over the course of the study, 69% of patients in the DFP group and 79% in the DFO group had acceptable compliance with treatment. Based on the Pocock's α spending function, a more stringent confidence level of 96.01% was applied to the calculation of confidence interval for the evaluation of non-inferiority. For the primary efficacy endpoint, the least squares (LS) mean change in LIC (measured as mg/g dw) was -4.04 for DFP, -4.45 for DFO; the upper limit of the 96.01% confidence interval for the difference was 1.57, thereby demonstrating non-inferiority of DFP to DFO. The upper limit for the subpopulation of patients with SCD also met the non-inferiority criterion. For the secondary endpoints, the change in cardiac iron (measured as ms on MRI T2*, log-transformed) was approximately -0.02 for both; and for SF (measured as μg/L), it was -415 vs. -750 for DFP vs. DFO, respectively. The difference between the groups was not statistically significant for both endpoints. With respect to safety, there was no statistically significant difference between the groups in the overall rate of adverse events (AEs), treatment-related AEs, serious AEs, or withdrawals from the study due to AEs. Agranulocytosis was seen in 1 DFP patient vs. no DFO patients, while events of less severe episodes of neutropenia occurred in 4 vs. 1, respectively. All episodes of agranulocytosis and neutropenia resolved. There was no significant treatment group difference in the rates of any of the serious AEs. Conclusion: The efficacy of DFP for the treatment of iron overload in patients with SCD or other rare anemias is not inferior to that of DFO, as assessed by changes in liver iron concentration. non-inferiority was supported by the endpoints on cardiac iron load and SF. The safety profile of DFP was acceptable and was similar to that previously seen in thalassemia patients, and its use was not associated with unexpected serious adverse events. The results of this study support the use of DFP for the treatment of iron overload in patients with SCD or other rare transfusion-dependent anemias. Note: The authors listed here are presenting these findings on behalf of all investigators who participated in the study. Disclosures Kwiatkowski: Terumo: Research Funding; Imara: Consultancy; bluebird bio, Inc.: Consultancy, Research Funding; Agios: Consultancy; Novartis: Research Funding; Celgene: Consultancy; Apopharma: Research Funding. Fradette:ApoPharma: Employment. Kanter:Sangamo: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Imara: Consultancy; Guidepoint Global: Consultancy; GLG: Consultancy; Cowen: Consultancy; Jeffries: Consultancy; Medscape: Honoraria; Rockpointe: Honoraria; Peerview: Honoraria; SCDAA: Membership on an entity's Board of Directors or advisory committees; NHLBI: Membership on an entity's Board of Directors or advisory committees; bluebird bio, Inc.: Consultancy; Modus: Consultancy, Honoraria. Tsang:Apotex Inc.: Employment. Stilman:ApoPharma: Employment. Rozova:ApoPharma: Employment. Sinclair:ApoPharma: Employment. Shaw:ApoPharma: Employment. Chan:ApoPharma: Employment. Toiber Temin:ApoPharma: Employment. Lee:ApoPharma: Employment. Spino:ApoPharma: Employment. Tricta:ApoPharma: Employment. OffLabel Disclosure: Deferiprone is an oral iron chelator.

The Effect of Supplemental Ascorbate on Defersirox Iron Chelation In the Iron-Loaded Gerbil

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2059-2059
Author(s):  
Maya Otto-Duessel ◽  
Casey Brewer ◽  
Aleya Hyderi ◽  
Jens Lykkesfeldt ◽  
Ignacio Gonzalez-Gomez ◽  
...  
Keyword(s):  
Iron Overload ◽  
Iron Content ◽  
Iron Concentration ◽  
Iron Chelation ◽  
Iron Dextran ◽  
Iron Loading ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Liver Iron Content ◽  
Wet Weight

Abstract Abstract 2059 Introduction: Iron dextran injections are often used to induce iron overload in rodents, for the purposes of assessing iron chelation therapy. In gerbils, we have previously described that deferasirox therapy preferentially clears hepatocellular iron when compared with reticuloendothelial stores. Ascorbate deficiency, which is common in humans with iron overload, produces similar profound disparities between reticuloendothelial and parenchymal iron stores. We postulated that iron-induced ascorbate deficiency might be exaggerating reticuloendothelial iron retention in gerbils receiving deferasirox therapy. This study examined the effect of supplemental ascorbate on spontaneous iron loss and deferasirox chelation efficiency in the iron-dextran loaded gerbil. Methods: 48 female gerbils underwent iron dextran loading at 200 mg/kg/week for 10 weeks. Sixteen animals were sacrificed at 11 weeks to characterize iron loading; eight were on standard rodent chow and eight had chow supplemented with 2250 ppm of ascorbate. 32 additional animals that were not ascorbate supplemented during iron loading transitioned into the chelation phase. Half were subsequently placed on ascorbate supplemented chow and both groups were assigned to receive either deferasirox 100 mg/kg/day five days per week or sham chelation. Animals received iron chelation for twelve weeks. Liver histology was assessed using H & E and Prussian blue stains. Iron loading was ranked and graded on a five-point scale by an experienced pathologist screened to the treatment arm. Iron quantitation in liver and heart was performed by atomic absorption. Results: Table 1 one summarizes the findings. During iron dextran loading, ascorbate supplementation lowered wet weight liver iron concentration but not liver iron content suggesting primarily changes in tissue water content. Spontaneous iron losses were insignificant, regardless of ascorbate therapy. Deferasirox lowered liver iron content 56% (4.7% per week) in animals without ascorbate supplementation and 48.3% (4.0% per week) with ascorbate supplementation (p=NS). Cardiac iron loading, unloading and redistribution were completely unaffected by ascorbate supplementation. Spontaneous iron redistribution was large (1.9% – 2.3% per week). Deferasirox chelation did not lower cardiac iron to a greater degree than spontaneous cardiac iron redistribution. Histologic grading paralleled tissue wet weight iron concentrations. Ascorbate treatment lowered the rank and absolute iron score in liver during iron loading (p=0.003) and there was a trend toward lower iron scoring in sham treated animals (p=0.13). Ascorbate had no effect on histological score or relative compartment distributions of iron in deferasirox chelated animals (p=0.5). Ascorbate supplementation was sufficient to increase total plasma ascorbate levels from 25 ± 12.2 uM to 38.4 ± 11 uM at 10 weeks (p=0.03). In the liver, ascorbate increased from 1203 ± 212 nmol/g of tissue to 1515 ± 194 nmol/g of tissue (p=0.01) with supplementation. No significant change in total ascorbate was observed in the heart. Discussion: We hypothesized that ascorbate supplementation might improve reticuloendothelial iron accessibility to deferasirox by facilitating redox cycling. Although gerbils synthesize their own ascorbate, supplementation was able to raise both serum and hepatic total ascorbate levels. However, increasing ascorbate did not change either the amount or distribution of tissue iron in deferasirox-treated animals. Disclosures: Nick: Novartis: Employment. Wood:Novartis: Research Funding; Ferrokin Biosciences: Consultancy.

Myocardial iron overload

2018 ◽  
pp. 364-374
Author(s):  
John P Carpenter ◽  
John C Wood ◽  
Dudley J Pennell
Keyword(s):  
Heart Failure ◽  
Iron Overload ◽  
Iron Concentration ◽  
Left Ventricular ◽  
Breath Hold ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Single Breath ◽  
Developing Heart ◽  
Cost Efficient

The heart is the target lethal organ in thalassaemia major. Cardiovascular magnetic resonance (CMR) measures iron using the magnetic relaxation time T2*. This allows comparison with the left ventricular function and conventional iron measurements such as liver iron and serum ferritin. The single breath-hold cardiac-gated CMR acquisition takes only 15 seconds, making it cost-efficient and relevant to developing countries. Myocardial T2* of <20 ms (increased iron) correlates with reduced left ventricular ejection fraction, but poor correlation exists with ferritin and liver iron, indicating poor capability to assess future risk. Myocardial T2* of <10 ms is present in >90% of thalassaemia patients developing heart failure, and approximately 50% of patients with T2* of <6 ms will develop heart failure within 1 year without intensified treatment. The technique is validated and calibrated against human heart iron concentration. The treatment for iron overload is iron chelation, and three major trials have been performed for the heart. The first trial showed deferiprone was superior to deferoxamine in removing cardiac iron. The second trial showed a combination therapy of deferiprone with deferoxamine was more effective than deferoxamine monotherapy. The third trial showed that deferasirox was non-inferior to deferoxamine in removing cardiac iron. Each drug in suitable doses can be used to remove cardiac iron, but their use depends on clinical circumstances. Other combination regimes are also being evaluated. Use of T2*, intensification of chelation treatment, and use of deferiprone are associated with reduced mortality (a reduction in deaths by 71% has been shown in the United Kingdom). The use of T2* and iron chelators in the heart has been summarized in recent American Heart Association guidelines.

Magnetic Ressonance Imaging (MRI) in the Evaluation of Iron Overload in Patients with Beta Thalassaemia. The Brazilian National Program Preliminary Results.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3825-3825
Author(s):  
Nelson Hamerschlak ◽  
Laercio Rosemberg ◽  
Alexandre Parma ◽  
Fernanda F. Assir ◽  
Frederico R. Moreira ◽  
...  
Keyword(s):  
Iron Overload ◽  
Ventricular Function ◽  
Iron Content ◽  
Chelation Therapy ◽  
Iron Concentration ◽  
Iron Chelation ◽  
Inverse Correlation ◽  
Liver Iron ◽  
Liver Iron Content ◽  
Cooperative Program

Abstract Magnetic Ressonance Imaging (MRI) using T2 star (T2*) tecnique appears to be a very useful method for monitoring iron overload and iron chelation therapy in thalassaemia. In Brazil, we have around 400 thalassaemic major patients all over the country. They were treated with hipertransfusion protocols and desferroxamine and/or deferiprone chelation. We developed a cooperative program with the Brazilian Thalassaemic Patients Association (ABRASTA) in order to developT2* tecnique in Brazil to submit brazilian patients to an annual iron overload monitoring process with MRI.. We performed the magnetic ressonance T2* using GE equipment (GE, Milwaukee USA), with validation to chemical estimation of iron in patients undergoing liver biopsy. Until now, 60 patients were scanned, median age=23,2 (12–54); gender: 18 male (30%) and 42 female (70%). The median ferritin levels were 2030 ng/ml (Q1=1466; Q3=3296). As other authors described before, there was a curvilinear inverse correlation between iron concentration by biopsy, liver T2*(r=0,92) and also there were a correlation with ferritin levels. We also correlated myocardial iron measured by T2* with ventricular function.. As miocardial iron increased, there was a progressive decline in ejection fraction and no significant correlation was found between miocardial T2* and the ferritin levels. Liver iron content can be predicted by ferritin levels. On the other hand, cardiac disfunction is the most important cause of mortality among thalassaemic patients. Since Miocardio iron content cannot be predicted from serum ferritin or liver iron, and ventricular function can only detect those with advance disease, intensification and combination of chelation therapy, guided by T2* MRI tecnique should reduce mortality from the reversible cardiomyopathy among thalassaemic patients.

Comparing the Value of Serum Ferritin, Transfusion History and Magnetic Resonance Imaging for the Prediction of Iron Overload In MDS and AML Patients Undergoing Allogeneic Stem Cell Transplantation.

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 3493-3493
Author(s):  
Martin Wermke ◽  
Jan Moritz Middeke ◽  
Nona Shayegi ◽  
Verena Plodeck ◽  
Michael Laniado ◽  
...  
Keyword(s):  
Iron Overload ◽  
Serum Ferritin ◽  
Iron Content ◽  
Iron Concentration ◽  
Transferrin Saturation ◽  
Resonance Imaging ◽  
Liver Iron Concentration ◽  
Liver Iron ◽  
Liver Iron Content ◽  
Transfusion History

Abstract Abstract 3493 An increased risk for GvHD, infections and liver toxicity after transplant has been attributed to iron overload (defined by serum ferritin) of MDS and AML patients prior to allogeneic hematopoietic stem cell transplantation (allo-HSCT). Nevertheless, the reason for this observation is not very well defined. Consequently, there is a debate whether to use iron chelators in these patients prior to allo-HSCT. In fact, serum ferritin levels and transfusion history are commonly used to guide iron depletion strategies. Both parameters may inadequately reflect body iron stores in MDS and AML patients prior to allo-HSCT. Recently, quantitative magnetic resonance imaging (MRI) was introduced as a tool for direct measurement of liver iron. We therefore aimed at evaluating the accurateness of different strategies for determining iron overload in MDS and AML patients prior to allo-HSCT. Serologic parameters of iron overload (ferritin, iron, transferrin, transferrin saturation, soluble transferrin receptor) and transfusion history were obtained prospectively in MDS or AML patients prior to allo-SCT. In parallel, liver iron content was measured by MRI according to the method described by Gandon (Lancet 2004) and Rose (Eur J Haematol 2006), respectively. A total of 20 AML and 9 MDS patients (median age 59 years, range: 23–74 years) undergoing allo-HSCT have been evaluated so far. The median ferritin concentration was 2237 μg/l (range 572–6594 μg/l) and patients had received a median of 20 transfusions (range 6–127) before transplantation. Serum ferritin was not significantly correlated with transfusion burden (t = 0.207, p = 0.119) but as expected with the concentration of C-reactive protein (t = 0.385, p = 0.003). Median liver iron concentration measured by MRI was 150 μmol/g (range 40–300 μmol/g, normal: < 36 μmol/g). A weak but significant correlation was found between liver iron concentration and ferritin (t = 0.354; p = 0.008). The strength of the correlation was diminished by the influence of 5 outliers with high ferritin concentrations but rather low liver iron content (Figure 1). The same applied to transfusion history which was also only weakly associated with liver iron content (t = 0.365; p = 0.007). Levels of transferrin, transferrin saturation, total iron and soluble transferrin receptor did not predict for liver iron concentration. Our data suggest that serum ferritin or transfusion history cannot be regarded as robust surrogates for the actual iron overload in MDS or AML patients. Therefore we advocate caution when using one of these parameters as the only trigger for chelation therapy or as a risk-factor to predict outcome after allo-HSCT. Figure 1. Correlation of Liver iron content with Ferritin. Figure 1. Correlation of Liver iron content with Ferritin. Disclosures: No relevant conflicts of interest to declare.

Efficacy of deferasirox in reducing and preventing cardiac iron overload in β-thalassemia

Blood ◽  
2010 ◽  
Vol 115 (12) ◽  
pp. 2364-2371 ◽  
Author(s):  
Dudley J. Pennell ◽  
John B. Porter ◽  
Maria Domenica Cappellini ◽  
Amal El-Beshlawy ◽  
Lee Lee Chan ◽  
...  
Keyword(s):  
Iron Overload ◽  
Iron Reduction ◽  
Geometric Mean ◽  
Iron Concentration ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Liver Iron ◽  
Ventricular Ejection Fraction ◽  
Cardiac Iron ◽  
Cardiac Iron Overload

Cardiac iron overload causes most deaths in β-thalassemia major. The efficacy of deferasirox in reducing or preventing cardiac iron overload was assessed in 192 patients with β-thalassemia in a 1-year prospective, multicenter study. The cardiac iron reduction arm (n = 114) included patients with magnetic resonance myocardial T2* from 5 to 20 ms (indicating cardiac siderosis), left ventricular ejection fraction (LVEF) of 56% or more, serum ferritin more than 2500 ng/mL, liver iron concentration more than 10 mg Fe/g dry weight, and more than 50 transfused blood units. The prevention arm (n = 78) included otherwise eligible patients whose myocardial T2* was 20 ms or more. The primary end point was the change in myocardial T2* at 1 year. In the cardiac iron reduction arm, the mean deferasirox dose was 32.6 mg/kg per day. Myocardial T2* (geometric mean ± coefficient of variation) improved from a baseline of 11.2 ms (± 40.5%) to 12.9 ms (± 49.5%) (+16%; P < .001). LVEF (mean ± SD) was unchanged: 67.4 (± 5.7%) to 67.0 (± 6.0%) (−0.3%; P = .53). In the prevention arm, baseline myocardial T2* was unchanged from baseline of 32.0 ms (± 25.6%) to 32.5 ms (± 25.1%) (+2%; P = .57) and LVEF increased from baseline 67.7 (± 4.7%) to 69.6 (± 4.5%) (+1.8%; P < .001). This prospective study shows that deferasirox is effective in removing and preventing myocardial iron accumulation. This study is registered at http://clinicaltrials.gov as NCT00171821.

Cardiac MRI (T2,T2*) Predicts Cardiac Iron in the Gerbil Model of Iron Cardiomyopathy.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 376-376 ◽  
Author(s):  
John C. Wood ◽  
Maya Otto-Duessel ◽  
Michelle Aguilar ◽  
Hanspeter Nick ◽  
Marvin D. Nelson ◽  
...  
Keyword(s):  
Cardiac Mri ◽  
Iron Content ◽  
Interstitial Fibrosis ◽  
Iron Concentration ◽  
Dry Weight ◽  
Weight Basis ◽  
Iron Deposition ◽  
Liver Iron ◽  
High Iron ◽  
Cardiac Iron

Abstract Introduction: Transfusional therapy for thalassemia major and sickle cell disease can lead to iron deposition and damage to the heart, liver, and endocrine organs. Iron causes the MRI parameters T1, T2, and T2* to shorten in these organs, creating a potential mechanism for iron quantitation. Validation of liver MRI has been achieved by studying patients undergoing clinically indicated liver biopsy. However, because of the danger and variability of cardiac biopsy, cardiac MRI studies have relied upon “clinical” validation, i.e., the association between low cardiac T2* and cardiac function. In this study, we demonstrate that iron produces similar T1, T2, and T2* changes in the heart and liver, using a gerbil iron overload model. Methods: Twelve gerbils underwent iron dextran loading (200 mg/kg/week) from 2–14 weeks; 5 age-matched controls were studied as well. Animals had in-vivo assessment of cardiac T2* as well as hepatic T2 and T2* using a General Electric 1.5 T CVi system with custom isofluorane anesthesia delivery system, imaging enclosure, coil and pulse sequences. Liver and heart were harvested following imaging, weighed, and portions collected for histology and quantitative iron (Mayo Metals Laboratory, Rochester, MN). Ex-vivo cardiac and liver T1 and T2 measurements were performed on fresh specimens (< 30 minutes post-sacrifice) using a Bruker minispectrometer. Results: Control animals had minimal detectable iron at baseline and did not accumulate iron in the liver or the heart over the 14-week study interval. Chemically-assayed heart iron concentration increased 0.078 mg/g(wet wt)/wk (r2=0.98) and iron content 0.022 mg/wk (r2=0.92) by linear regression analysis. Similarly, assayed liver iron concentration increased 1.15 mg/g(wet wt)/week (r2=0.93) over a 10 week interval and liver iron content increased 3.82 mg/wk (r2=0.96). Liver iron deposition was prominent in both sinusoidal cells and hepatocytes. Interstitial fibrosis was mild and there was no necrosis. Cardiac iron deposition was predominantly endomysial, generally sparing the myocytes themselves. Interstitial fibrosis was prominent, originating from areas of high iron concentration. No myocyte necrosis was observed, however myocyte hypertrophy was evident at high iron concentrations. Cardiac and liver R2* (1/T2*), R2 (1/T2), and R1 (1/T1) rose linearly with tissue iron concentration (r2 averaged 0.94 [0.74 to 0.98]. The slope of these parameter with respect to iron was15–29% steeper in heart than in liver, although these differences reached statistical significance only for R2. Systematic differences in wet-to-dry weight ratio between heart and liver (5.07 vs 3.82) antagonized this effect, however, such that calibrations were similar on a dry-weight basis. Conclusion: Cardiac iron is the primary determinant of cardiac MRI relaxivity. Calibration curves were similar between heart and liver on a dry weight basis. Extrapolation of liver calibration curves to heart may be a rationale approximation in humans where direct tissue validation is difficult and dangerous. Regardless of systematic differences in absolute calibration, these data support prior claims that cardiac R2 and R2* measurements reflect cardiac iron concentration

Clinical Relevance of Cardiac Iron Overload Estimated by MRI T2* in Regularly Transfused Low Risk MDS.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2666-2666 ◽  
Author(s):  
C. Ferte ◽  
O. Ernst ◽  
O. Beyne-Rauzy ◽  
M.P. Chaury ◽  
S. Brechignac ◽  
...  
Keyword(s):  
Iron Overload ◽  
Cardiac Mri ◽  
Iron Content ◽  
Clinical Signs ◽  
Left Ventricular ◽  
Low Risk ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Cardiac Symptoms ◽  
Cardiac Iron Overload

Abstract Background: Cardiac iron overload is the first cause of mortality in thalassemia. In MDS, a causal relationship between cardiac iron overload and death is not as well established and heart complication may be of intricate origins in these elderly pts. Cardiac MRI T2* allows accurate measurement of heart iron and is influenced by iron content only (and not by other cardiac diseases). T2* value < 20ms is clearly associated with cardiac iron overload. A few reports (Winder et al ASH 2005, Chacko J BJH2006;133: supp1) showed no cardiac iron overload by T2* in small numbers of multitransfused MDS. We performed a similar analysis in our transfused low risk MDS pts. Methods: We prospectively evaluated by MRI both cardiac T2* according to Anderson (Eur Heart J 2001) and liver iron content (LIC ) according to Gandon (Lancet 2004) and cardiac function by echocardiography in multitransfused low risk MDS pts. Cardiac MRI T2* was also assessed in 33 controls. Results: 21 MDS were analyzed, 9M/12F. Median age: 75 years ( 50–83); FAB : RA= 3, RAS=13, RAEB = 3, CMML n=1, unclassified n=1. Karyotype: fav n= 1, Int n= 18, failure n=1. IPSS: low n= 10, Int I n= 10, unavailable n=1. Median interval from MDS diagnosis and first transfusion was 40 and 24 months respectively. At inclusion, median number of RBC units transfused was 81 (range 6–282, and greater than 100 in 8 pts). Median serum ferritin level was 2152 ng/ml and 11 patients were on chelation therapy (CT). 9/21 pts had cardiac symptoms and were on cardiac therapy. LVEF was below normal (55%) in 3/21 cases. Left ventricular telediastolic diameter LVTD was above normal (normal 53 mm) in 6/14 pts evaluated. Median LIC was 350 micromoles/g/dw (95–898 ). Median Cardiac T2* was 27 ms (8–74) and did not differ significantly from controls (T2*=27ms+/−6.4). No correlation was found between cardiac T2* and ferritin, LIC, LVEF, time from MDS diagnosis. However 3/21 pts had cardiac iron overload with T2* < 20 (18ms,15ms,8ms respectively). LVEF and number of RBC units transfused of these pts was respectively 69%,51%,33% and 119,150,282 RBC units. Two of them were on iron CT, one of them since 8 years. The last 2 pts had clinical signs of cardiac failure unexplained by other causes and both had increased LVTD. Conclusions: Although cardiac T2* did not differ significantly in transfused MDS and in controls, 3 heavily transfused (all in the 8 patients who had received >100 RBC units) had clear cardiac iron overload, clinically relevant in 2 of them and not correlated with higher liver iron overload. Differences between our study and previous studies could be due to the higher number of transfused RBC units in our pts with abnormal T2*, as compared to a median of 50 in the study of Winder, but further studies are required to confirm this finding.

Serum Ferritin Predicts Liver but Not Cardiac Iron Burden by Noninvasive MRI in Sickle Cell Disease (SCD.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1421-1421 ◽  
Author(s):  
Robert I. Liem ◽  
Cynthia Rigsby ◽  
Richard J. Labotka ◽  
Andrew DeFreitas ◽  
Alexis A. Thompson
Keyword(s):  
Iron Overload ◽  
Serum Ferritin ◽  
Iron Content ◽  
Iron Loading ◽  
Cell Disease ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Liver Iron Content ◽  
The Mean

Abstract BACKGROUND: Assumptions about iron loading as well as the utility of ferritin to predict transfusional iron overload among individuals with sickle cell disease (SCD) are largely based on extrapolation from data generated in patients with thalassemia major (TM). Yet recent studies suggest the natural history of iron overload in patients with SCD differs significantly from chronically transfused patients with TM. We sought to evaluate the extent of myocardial and hepatic siderosis using noninvasive imaging in chronically transfused patients with SCD and examine its clinical associations, including relationship to long-term trends in serum ferritin, transfusion history, chelation status and markers of hemolysis and inflammation. METHODS: We evaluated 17 subjects (mean age 15±3.6 yrs, range 9 to 20). The mean transfusion duration was 7.3±3.6 yrs (range 2 to 15). Thirteen (76%) patients were on chelation with deferasirox at the time of screening; 4 were not on chelation Rx. MRI T2*/R2* of the heart and liver using a multiple gradient echo sequence was performed on a single 1.5T GE scanner. Hepatic iron concentration (HIC) values were predicted from liver R2* values. RESULTS: Mean HIC in subjects was 9.9±6.7 mg/gm liver dry weight (range 2.5 to 20.8) and was ≥15 mg/gm in 6/17 (35%) subjects. The mean long-term serum ferritin (past 5 yrs, or duration of transfusion if &lt; 5yrs) was 2318±1122 ng/mL (range 541 to 4225). Using Pearson’s correlation coefficient, we observed a significant relationship between HIC and ferritin (r=0.765, p=&lt;0.001). We generated a receiver operator characteristic (ROC) curve to assess the utility of ferritin as a predictor of elevated HIC, using a threshold HIC thought to predict serious iron-related complications. A ferritin cut-off value ≥2164 ng/mL correctly identified 80% of cases of HIC ≥15 mg/gm (AUC 0.96, p=0.003) in our subjects with 83% sensitivity and 73% specificity. Despite markedly elevated HIC and ferritin values in some subjects, none had myocardial siderosis. All 17 subjects had cardiac MRI T2* values in the normal range &gt; 25 ms. Cardiac iron load measured by T2* did not correlate with HIC or serum ferritin. We examined C-reactive protein (CRP) and B-type natriuretic peptide (BNP) as markers for inflammation and myocardial strain, respectively, in our subjects but neither demonstrated a significant relationship to ferritin or MRI findings. BNP, however, did correlate modestly with both age (r=−0.574, p=0.013) and left ventricular ejection fraction on cardiac MRI (r=0.510, p=0.036). A subset of subjects (n=8) had histologic iron measurements by percutaneous liver biopsy (LBx) within 6 months of MRI. While liver iron content by LBx correlated significantly with HIC by MRI (r=0.759, p=0.03), liver iron content by LBx did not correlate with ferritin (r=0.312, p=0.452). CONCLUSION: We found that serum ferritin is a good predictor of liver iron by MRI R2*, and that long term ferritin values ≥2164 ng/mL predict significant hepatic iron overload as assessed by this noninvasive method. We did not observe appreciable cardiac iron loading in our subjects with SCD, which otherwise might have been predicted by elevated HIC alone, as in individuals with TM. These data suggest that reliable, long term surveillance of transfusion-induced iron overload in SCD may be achieved using serum ferritin and HIC by MRI R2* as surrogate markers of hepatic siderosis rather than relying on liver iron content measured invasively by LBx. Also, previously determined thresholds for significant cardiac iron loading in TM, based on degree of hepatic siderosis, may not be applicable in SCD. Further investigation into alternative mechanisms of iron loading or distribution in these related but distinct disorders is warranted.

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