Left Ventricular Dysfunction in Chronically Transused Patients with Sickle Cell Anemia and Thalassemia.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3745-3745
Author(s):  
Lynne Neumayr ◽  
Ellen Fung ◽  
Paul Harmatz ◽  
Ellen Butensky ◽  
John Wood ◽  
...  
Keyword(s):  
Iron Overload ◽  
Sickle Cell ◽  
Cardiac Mri ◽  
Left Ventricular ◽  
Iron Toxicity ◽  
Iron Deposition ◽  
Liver Iron ◽  
Transfusion Therapy ◽  
Cardiac Iron ◽  
Lv Dysfunction

Abstract BACKGROUND: Iron-induced cardiomyopathy has been extensively described in thalassemia (THAL) patients. Left ventricular (LV) dysfunction is the leading cause of death in THAL, with prevalence estimates ranging from 6% to 23%. Recent MRI techniques confirmed that T2* measurements consistent with elevated cardiac iron are associated with LV dysfunction and early mortality. Transfusion therapy is being increasingly used for the treatment and prevention of complications in sickle cell disease (SCD). By adulthood, the majority of SCD patients will have received multiple transfusions and nearly 1/3 will be iron-overloaded. However, cardiomyopathy, its prevalence, and the role of iron toxicity have not been studied in SCD. The Multicenter Study of Iron Overload, a 5-year prospective natural history study, enrolled 152 transfusion dependent THAL, 204 chronically transfused SCD (txSCD) and 64 control SCD in order to compare the effects of iron toxicity in these two diseases. We compared the prevalence of LV dysfunction and its relationship to iron-toxicity in THAL, txSCD and control SCD. METHODS AND RESULTS: Baseline or year 1 echocardiograms (ECHOs) were available in 45% of the patients (80 THAL, 94 txSCD and 16 SCD controls) and reviewed for evidence of LV dysfunction, defined as an ejection fraction ≤ 55% or shortening fraction ≤ 28%. Pulmonary hypertension (PHT) was defined as a tricuspid regurgitant jet velocity (TRV) ≥ 2.5 m/s or pulmonary artery pressure (PAP) ≥ 35 mmHg. ECHOs reported as normal, even without TRV or PAP recorded, were assumed to be negative for PHT. At study entry, THAL and txSCD patients were severely iron over-loaded and their average ferritin and liver iron concentrations were not significantly different: 3506 g/dl and 20 mg/g dry weight. (Serum ferritin in the control SCD was 120 g/dl.) The average age of the patients was 30.3 ± 12 yrs, and did not differ across the three groups. LV dysfunction was found in 22% THAL; THAL patients with LV dysfunction had been transfused longer than those with normal ECHOs (26.5 vs. 21.1 yrs, p=. 03). A subgroup of THAL was screened with cardiac MRI: 11/21 (52%) had evidence of cardiac iron deposition, 4 of these patients (36%) had LV dysfunction. In THAL screened with MRI, all patients with LV dysfunction had cardiac iron deposition. LV dysfunction was seen in 14% of txSCD but in 0% of the control SCD. txSCD patients with LV dysfunction were older (43.7 vs. 28.5, p <. 0001) and more likely to have PHT (75% vs. 22%, p < .001). PHT was more common in txSCD than THAL (29% vs. 15%, p=. 03) and found in 13% of the control SCD group. No txSCD patients were screened with MRI. CONCLUSIONS: LV dysfunction is common in transfusion dependent THAL and associated with duration of transfusion and iron deposition. In SCD, patients with cardiomyopathy were chronically transfused, older, and more likely to have PHT. SCD patients are developing iron overload similar to THAL; cardiac MRI studies are essential for the evaluation of iron deposition and its relationship to cardiomyopathy.

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.

T2* MRI Provides No Evidence for Myocardial and Pancreatic Iron Overload in Multitransfused Patients with Sickle/β-Thalassemia.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1422-1422 ◽  
Author(s):  
Hussam Ghoti ◽  
Orly Goitein ◽  
Elie Konen ◽  
Ariel Koren ◽  
Carina Levin ◽  
...  
Keyword(s):  
Iron Overload ◽  
Serum Ferritin ◽  
Iron Content ◽  
Transferrin Saturation ◽  
Left Ventricular ◽  
Iron Deposition ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Cardiac Iron Overload ◽  
T2 Mri

Abstract Introduction: Transfusion-dependent hemolytic anemias particularly thalassemia major (thal.m) and also sickle cell disease (SCD) result in iron deposition in the reticuloendothelial system in major organs, mainly in the liver and also in the heart and endocrine glands. However, liver iron levels in patients with thal.m measured by other techniques were found to have no predictive values for the extent of their cardiac iron deposition. T2* MRI sequences have been previously addressed as a reliable tool for non invasive evaluation of iron load in the liver, heart and pancreas. Patients with T2* value &gt; 20 ms have normal cardiac function while the prevalence of myocardial dysfunction and arrhythmias increases as a consequence of cardiac iron overload (T2* &lt; 20 ms). A previous study comparing cardiac iron overload in transfusion dependent thal.m and SCD patients matched for age and liver iron content, found abnormally low cardiac T2* values (&lt;20 ms) in nearly 40% of patients with thal.m, while the T2* values were normal in the patients with SCD (1) (Blood:103;1934, 2004). The purpose of the present study was to quantify iron content (T2* values) in the liver, heart and pancreas of multitransfused patients with sickle/β-thal. Patients and Methods: Eleven patients with sickle/β-thal., 3 males and 8 females, mean age 31 years ± 9.5 (SD) were analyzed, 6 of them were splenectomized. Their mean ± SD values for hemoglobin was 9.0 gr/dl, for serum ferritin - 3900 ng/ml ± 3944 and for transferrin saturation - 80% ± 23. All of them were transfused and received a mean of 97 packed cell units ± 88 (SD). Only one patient received iron chelation for 10 months until 6 months prior to entering the study. Seven patients received regularly Hydrea 1–1.5 gr/day for &gt; 10 years. MRI evaluation (1.5T, GE MRI system) included: Left ventricular (LV) function (ejection fraction)- steady-state free procession (SSFP) cine sequence as well as iron load quantification- breath-hold multi echo gradient echo T2*, sampled across regions of interest in the LV septum, liver parenchyma and pancreatic tissue. (Eur. Heart J22:2171, 2001) Results: All patients had normal T2* values in the heart (&gt;20ms) and in the pancreas (&gt;30ms). The left ventricular ejection fraction, left ventricular endsystolic and endiastolic volumes (evaluated both by echo-cardiography and by cine function MRI) were normal in all patients. There was no evidence for pleural or pericardial effusion. The diameter of the pulmonary artery and right ventricle were normal. Seven patients demonstrated evidence of mild to moderate iron deposition in the liver (T2* &lt;6.3 ms). In these patients mean serum ferritin (5656 ng/ml) and transferrin saturation (92.4%) were significantly higher (p=0.001) than in 4 patients with normal T2* levels in the liver (&gt;6.3ms) where mean serum ferritin was 872ng/ml and transferrin saturation 59.5%. Conclusion: The T2* MRI values of 11 patients with sickle/β-thal. showed that whereas 7 patients had a certain degree of iron deposition in the liver, none demonstrated cardiac or pancreatic iron deposition. Therefore, with respect to iron deposition, multitransfused patients with sickle/β-thal. are similar to patients with homozygous SCD and not to patients with thal.m and thal intermedia. The reasons for this observation are still unclear. This similarity could be related in part to the relativly low number of transfusions, starting later in life, of patients with homozygous SCD or sickle/β- thal. compared to patients with thal.m. (1) The liver is the dominant iron storage organ and iron liver concentration correlates closely with the total body iron content. While iron uptake by hepatocytes is predominately mediated via transferrin and correlates with serum ferritin levels, as confirmed in the present study, this is not the case in regulation of cardiac and endocrine iron uptake. These organs might acquire the excess metal differently. It is possible that additional and/or different forms of iron, which have been identified, such as non-transferrin bound iron and labile plasma iron, are involved in determining iron loading in the heart and endocrine glands and/or because regulation of iron entry into the plasma by hepcidin might differ. Additional studies are in progress to address these issues.

Onset of Cardiac Iron Loading in Pediatric Patients.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2765-2765
Author(s):  
John C. Wood ◽  
Raffaella Origa ◽  
Annalisa Agus ◽  
Gildo Matta ◽  
Thomas D. Coates ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Los Angeles ◽  
Iron Overload ◽  
Cardiac Mri ◽  
Pediatric Patients ◽  
Thalassemia Major ◽  
Cardiac Complications ◽  
Liver Iron ◽  
Transfusion Therapy ◽  
Cardiac Iron

Abstract Patients with thalassemia major develop life threatening cardiac complications in their teens and twenties from iron overload. Cardiac MRI allows us to diagnosis preclinical cardiac iron deposition, but it is not known at what age T2* screening should be initiated. Historical data and pilot MRI studies suggest that patients must reach a critical transfusional exposure prior to cardiac iron uptake. This study was a two-institution characterization of the prevalence of cardiac iron overload in 77 pediatric patients. Methods: Study was performed at the Ospedale Regionale Microcitemie in Cagliari and the Childrens Hospital Los Angeles (CHLA). Retrospective review of medical records was authorized by the IRB for pediatric patients undergoing cardiac MRI prior to July of 2007. Subjects at both institutions had assessment of cardiac T2* and cardiac function using validated techniques on a 1.5 T General Electric CVi scanner; patients at CHLA also underwent MRI-based liver iron measurements. Complete transfusional iron burden was measured in the Italian patients. Serial MRI data was recorded in 30 patients, but associations between cardiac T2* and age were determined using linear and logistic regression using only results from the first patient MRI scan. Results: Patient ages ranged from 8.0 to 18 years of age at Cagliari (n=36) and 2.5 to 17.9 years of age at CHLA (n=41), reflecting the use of MRI to monitor liver iron in patients < 8 years of age. Patients were moderately iron loaded with hepatic iron concentrations of 12.7 ± 9.8 (CHLA) and ferritin values of 2329 ± 1162 (Cagliari). Median cardiac T2* was 30.2 and ranged from 3.4 to 72.8. Cardiac T2* and its reciprocal were uncorrelated with liver iron (CHLA) and ferritin levels (Cagliari). Figure 1 demonstrates the decrease in cardiac T2* with increasing chronologic age. Serial data are connected by lines. Although linear regression was weakly positive (r2 = 0.06, p = 0.03), the relationship was fundamentally nonlinear. No patient below the age of 9.5 years of age demonstrated an abnormal cardiac T2* (< 20 ms) while 36% of patients between the ages of 15–18 years had detectable cardiac iron. Figure 2 demonstrates the logistic regression curve modeling the prevalence of detectable cardiac iron as a function of age (r2= 0.13, p< 0.002). Chronologic age was highly correlated (r2 = 0.88) with both transfusional iron burden and with duration of transfusion therapy, making it impossible to separate the relative importance of these three variables. Conclusion: Thalassemia major patients did not accumulate cardiac iron until early in their second decade of life. Consequently, cardiac iron monitoring can be safely deferred until children are able undergo MRI examination without sedation. Figure Figure Figure Figure

Extrahepatic Iron Deposition In Chronically Transfused Children With Sickle Cell Anemia – Baseline Findings From The Twitch Trial

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2238-2238 ◽  
Author(s):  
John C. Wood ◽  
Alan Cohen ◽  
Banu Aygun ◽  
Hamayun Imran ◽  
Lori Luchtman-Jones ◽  
...  
Keyword(s):  
Iron Overload ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Research Funding ◽  
Iron Concentration ◽  
Dry Weight ◽  
Iron Deposition ◽  
Liver Iron ◽  
Transfusion Therapy ◽  
Upper Limits

Abstract Introduction Chronic transfusion therapy is the standard of care for children with sickle cell anemia (SCA) and abnormal transcranial Doppler velocities. Although effective, monthly transfusions are costly, inconvenient, and produce iron overload in the liver and extrahepatic organs. The TWiTCH study (ClinicalTrials.gov NCT01425307) is a randomized clinical trial to determine whether hydroxyurea therapy leads to comparable time averaged TCD velocities as conventional transfusion therapy, while reducing somatic iron stores. We report baseline data on iron burden in the spleen, pancreas, and kidneys from the TWiTCH cohort. Methods Pediatric patients from 22 centers underwent screening R2* assessment of the liver, spleen, pancreas, and kidneys. All sites used a 1.5 Tesla magnet, torso phased array coils, and a multiple echo gradient echo sequence with a minimum echo time ≤1.3 ms. Images were analyzed centrally at Children’s Hospital Los Angeles; core laboratory staff were blinded to patient, site, and visit data. Raw R2* values were used as iron surrogates for spleen, pancreas, and kidney. All statistics were performed by the TWiTCH Data Coordinating Center. Results A total of 113/159 enrolled patients (mean age 8.8 ± 6.3 years) successfully completed baseline abdominal R2* assessment (Table 1). Patients had received chronic transfusions for 4.2 ± 2.4 years and iron chelation for 3.2 ± 2.2 years. Serum ferritin values ranged from 191 to 10593 ng/ml (2655.6 ± 1668.1 ng/ml). All subjects had liver iron detectable by R2*, with 51.3% having liver iron concentration (LIC) >7 mg/g, and 13.3% >15 mg/g of dry weight. Splenic R2* could be assessed in 80/113 (71%) subjects, with the remainder having surgical splenectomy or autoinfarction. Splenic R2* revealed splenic tissue was comparable to liver tissue containing on average 13.1 mg Fe/g of dry weight. Pancreas R2* was greater than the upper limits of normal in 39.3% but no values exceeded 100 Hz (the level associated with pancreas dysfunction, pituitary iron accumulation, and cardiac iron deposition in thalassemia patients). LIC was the only significant predictor of pancreas R2* (r2 = 0.06, p=0.001). Kidney R2* was above the upper limits of normal in 79.5% of the patients and demonstrated preferential cortical distribution. Kidney R2* positively correlated with lactate dehydrogenase levels (p < 0.001), positive correlated with LIC R2* (p=0.005) and negatively correlated with hemoglobin level(p = 0.01) with a combined r2 of 0.29. No association was found with total bilirubin or reticulocyte count. Discussion This represents the first multicenter study documenting the prevalence and extent of extrahepatic iron deposition in children with SCA receiving chronic transfusions. Splenic iron deposition was common but uncorrelated with LIC,, suggesting different kinetics of iron loading transport. Clinically-significant pancreatic iron deposition was not observed. Renal R2* tracked with intravascular hemolysis markers, rather than LIC or ferritin, consistent with tubular uptake of filtered cell-free hemoglobin. Overall, chronically transfused children with SCA have greater splenic and renal iron deposition, but much milder pancreatic iron overload, than that observed in transfused thalassemia patients. Disclosures: Wood: Novartis: Honoraria; Apopharma: Honoraria, Patents & Royalties; Shire: Consultancy, Research Funding. Off Label Use: Hydroxyurea is FDA-approved for use in adults but not children. Thompson:Amgen: Research Funding; Eli Lilly: Research Funding; Glaxo Smith Kline: Research Funding; ApoPharma: Consultancy, Honoraria; Novartis: Consultancy, Research Funding; bluebird bio: Research Funding.

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.

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

Serum Ferritin in Children with Sickle Cell Disease on Chronic Transfusion: Measure of Iron Overload or End Organ Injury? STOP/STOP II Liver Iron Ancillary Study.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 791-791 ◽  
Author(s):  
Tom Adamkiewicz ◽  
Miguel R. Abboud ◽  
Julio C. Barredo ◽  
Melanie Kirby-Allen ◽  
Ofelia A. Alvarez ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Iron Overload ◽  
Sickle Cell ◽  
Serum Ferritin ◽  
Iron Removal ◽  
Organ Injury ◽  
Cell Disease ◽  
Liver Iron ◽  
Flow Measurements ◽  
Transfusion Therapy

Abstract Between 1995 and 2004, two NIH-sponsored studies (STOP/STOP II) showed that children with sickle cell disease (SCD) and abnormal transcranial Doppler blood flow measurements (high stroke risk) are protected from stroke with regular blood transfusions. Iron overload, which may lead to complications and requires iron removal therapy, was monitored by serum ferritin (SF). Liver iron concentration (LIC) measurement was not mandated by protocol and was performed at investigator discretion. Biopsy dates and lab values were captured during STOP/STOP II, providing an opportunity to validate SF against LIC. 75 LICs on 36 patients (19 female, 17 male) at 8 centers were obtained. No liver biopsy complications were reported. LICs were correlated with STOP/STOP II core laboratory SF and alanine aminotransferase (ALT) obtained within 180 days of LICs. Median age at first biopsy was 11.1 years (range, 4.5–17.8), median time from start of transfusion was 36 months (range, 2–100). Iron removal treatment was initiated a median 23 months (range, 4–108) from start of transfusion, with deferoxamine (n=27), and/or exchange transfusion (n=9). 21 pts (58%) had multiple LIC measures: 2 (n=9), 3 (n=8), 4 (n=2), 5 (n=2). Last LICs on iron removal therapy were obtained a median 72 months (range, 35–124) from start of transfusion. Correlation between SFs and LICs were r=-0.06 (n=18) for first LICs obtained prior to iron removal therapy, r=0.50 (n=17) for last LICs obtained on iron removal therapy, and r=0.51 for all LICs (n=60). Pts with single/last LIC &gt;=15 mg/gram dry liver were significantly more likely to have ALTs &gt;=45 IU/L compared to those with LICs &lt;15 mg/gram (5/12 vs. 1/18; odds ratio 12.1; 95% CI 1.2–123.6; p=0.03). Pts with LIC &gt;=15 mg/gram and ALT &gt;=45 IU/L tended to have higher SFs then those with normal ALT (mean SF 4927 ng/ml, 95% CI 1739–8115 vs. mean SF 2255 ng/ml, 95% CI 1599–2912). 37% (7/19) of pts with LIC &gt;=15 mg/gram had SFs &lt;2000 ng/ml. 55% (11/20) of pts with repeated LICs, had last LICs &lt;15 mg/gram after initiation of iron removal therapy. SF did not correlate with LICs after initiation of blood transfusion therapy and correlated weakly after initiation of iron removal therapy. Over 1/3 of children with evidence of significant iron overload, as measured by LICs, had low serum SFs (&lt;2000 ng/ml), leading to a potentially erroneous interpretation of low iron stores. A significant portion of pts with elevated LICs had evidence of liver injury (ALT elevation). SF elevation observed in some pts may be due in part to end organ injury. Sustained iron overload control was achieved in over 1/2 of pts examined with repeated LICs.

Initial Liver Iron Predicts Cardiac Chelation Efficacy of Deferasirox (Exjade®) Monotherapy in Chronically Transfused β-Thalassemia (β-Thal) Patients: 18- and 24-Month Data.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4069-4069
Author(s):  
John C. Wood ◽  
Alexis A. Thompson ◽  
Carole Paley ◽  
Tara Glynos ◽  
Barinder Kang ◽  
...  
Keyword(s):  
Iron Overload ◽  
Board Of Directors ◽  
Research Funding ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Employment Equity ◽  
Advisory Committees ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Equity Ownership

Abstract Abstract 4069 Poster Board III-1004 Introduction Transfused patients with β-thal major are known to experience clinical consequences of cardiac iron overload despite the widespread use of iron chelation therapy. Approximately 71% of patients will suffer cardiomyopathy, congestive heart failure (CHF) and death. Previous trials have confirmed the efficacy of deferasirox (Exjade®) in removing cardiac iron in patients with β-thal major. This ongoing study evaluates the effects of deferasirox on cardiac iron and left ventricular ejection fraction (LVEF) in patients with β-thal major in a prospective, single-arm, multi-center trial using cardiac MRI T2*. All patients have completed 18 months of therapy and we also report preliminary results from 24 months. Methods 28 patients were enrolled at four US centers. Entry criteria included MRI evidence of cardiac iron (T2* <20 ms) and normal LVEF (≥56%). Deferasirox was administered at 30–40 mg/kg/day for 18 months. Following core study completion (18 months), patients could continue treatment for an additional 6 months if their 18-month cardiac T2* was <20 ms and they demonstrated ≥25% improvement in cardiac T2* or LIC from baseline. Serum ferritin (SF) was assessed monthly. Liver iron concentration (LIC), cardiac T2* and LVEF were assessed by MRI every 6 months. Serum creatinine (SCr), biochemical and hematological status were also monitored. All results are reported as mean ± SE (range) unless otherwise stated. Baseline: All 26 evaluable patients (7 M/19 F; aged 10–44 years) received ≥150 lifetime transfusions. SF was 4307 ± 613 ng/mL (312–12,655), cardiac T2* was 9.5 ± 0.8 ms (1.8–16.1), LIC was 20.6 ± 3.15 mg Fe/g dry weight (dw; 3.6–62.3) and LVEF was 61.8 ± 0.8%. Results At the time of analysis, 22 and 9 patients had 18- and 24-month evaluations, respectively. Six patients discontinued the core trial due to patient decision (n=2), adverse events (AEs; n=2) or abnormal lab tests (n=2). Two of these patients died after discontinuing; the first enrolled with markedly elevated baseline cardiac iron (T2* = 1.8 ms) and died secondary to CHF. The second patient withdrew due to an AE and died 2 months later due to sepsis and multi-organ failure. 18-month results: At 18 months, 10/22 patients were on 40 mg/kg/day. The mean improvement in cardiac T2* from baseline in all patients was 2.2 ms (22%; P=0.016), with 13 patients improving, four remaining stable (T2* change <10%) and five worsening. Baseline LIC was a powerful predictor of response (Figure); cardiac T2* in 14 patients with LIC <18.5 mg Fe/g dw improved 2.2% per month, with 13/14 patients showing large improvements and one patient remaining stable. In contrast, in eight patients with LIC >18.5 mg Fe/g dw, mean T2* worsened 1.4% per month (P<0.0001); three patients remained stable and five worsened significantly. Improvements in cardiac iron were correlated with changes in LIC (r2 = 0.27, P=0.013). In general, initial T2* did not predict therapeutic response, although all three patients with T2* <6 ms increased their cardiac iron. LIC decreased 4.1 mg Fe/g dw over the study interval (P=0.003). LVEF remained stable. 24-month results: At 24 months, 7/9 patients were on 40 mg/kg/day. Relative to the 18-month time-point, 8/9 patients (89%) increased their cardiac T2*, with a mean improvement of 2.7% per month. Mean LIC, SF and LVEF were unchanged over the extension. Safety parameters from patients treated with 30–40 mg/kg/day deferasirox (n=25) were in line with previous studies at 20–30 mg/kg/day. Conclusions Deferasirox monotherapy resulted in statistically significant improvements in cardiac and hepatic iron after 18 months. Baseline LIC <18.5 mg Fe/g dw was a strong predictor of favorable response. LVEF remained stable during the study. Patients in the extension (18–24 months) improved their cardiac T2* without further improvements in LIC or SF. Deferasirox monotherapy at 30–40 mg/kg/day provides good cardiac chelation in patients with moderate cardiac and liver iron burdens. More aggressive therapy is warranted for more severe iron overload. Disclosures: Wood: Novartis: Research Funding. Thompson:Novartis: Research Funding. Paley:Novartis Pharmaceuticals: Employment, Equity Ownership. Glynos:Novartis Pharmaceuticals: Employment. Kang:Novartis Pharmaceuticals: Employment, Equity Ownership. Giardina:Novartis: Research Funding, Speakers Bureau. Harmatz:Ferrokin: Membership on an entity's Board of Directors or advisory committees; Apotex: Membership on an entity's Board of Directors or advisory committees. Coates:Hope Pharma: Consultancy, Research Funding; Sangart Pharma: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau.

Cardiac Iron Overload Causes Clinically Evident Heart Failure and Arrhythmia in Sickle Cell Anemia Patients: Evidence From Three Cases

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4846-4846
Author(s):  
Bhakti P. Mehta ◽  
Vasilios Berdoukas ◽  
Mammen Puliyel ◽  
Adam Bush ◽  
Thomas Hofstra ◽  
...  
Keyword(s):  
Heart Failure ◽  
Iron Overload ◽  
Sickle Cell ◽  
Research Funding ◽  
Chelation Therapy ◽  
Liver Iron ◽  
Cardiac Iron ◽  
Cardiac Iron Overload ◽  
Clinical Heart Failure ◽  
Symptoms And Signs

Abstract Abstract 4846 Transfusional iron overload is associated with poor outcomes in sickle cell disease (SCD). Unlike in thalassemia major (TM), there is no evidence that the iron overload per se causes morbidity in SCD. We present two patients with clear evidence of heart failure and arrhythmia secondary to transfusion induced cardiac iron overload, whose symptoms and signs completely resolved after a short period of intensive iron chelation. We studied 134 patients with SCD with magnetic resonance imaging (MRI). Over 50% of patients with TM and 70% of patients with transfusion dependent Diamond Blackfan Anemia demonstrate cardiac iron overload. We reviewed 472 MRIs in 134 patients with SCD. The median liver iron concentration (LIC) was 10.2 mg/g dry weight (dw). Ten percent of the patients had liver iron > 35mg/g dw. Three (2.2%) demonstrated cardiac iron overload. Patient 1 is now 27 years old and began transfusions at the age of 15 years because of pulmonary hypertension. The first MRI performed at the age of 22 years showed LIC >50 mg/g dw and a cardiac R2* of 128 sec−1 (T2* 7.8 ms) that indicates severe cardiac iron load. At this time she was changed from deferasirox to continuous infusion of desferrioxamine. After 6 months the LIC was 47 mg/g dw and her cardiac R2* was 123sec−1 (T2* 8.1ms). She had dyspnea on mild exertion, ankle edema, and orthopnea. Her left ventricular ejection fraction (LVEF) by MRI at that time was 45%. She started intensive chelation therapy with deferiprone (on compassionate basis) 100mg/kg/day and deferasirox 40mg/kg/day. Her symptoms and signs of clinical heart failure resolved within two months. She remains asymptomatic. After 7 months cardiac R2* is 88 sec−1 (T2*11.3ms) with an LVEF of 55% and LIC of 36 mg/g dw. Patient 2 is now 32 years of age. She started regular blood transfusions at the age of 9 years. Her first MRI at the age of 27 years showed a LIC of >60 mg/g dw and no evidence of cardiac iron overload with a cardiac R2* of 29 sec−1(T2* 34.9ms) with an LVEF of 61%. After 2.5 years her cardiac R2* was 68 sec−1 (T2* 14.7 ms) with an LVEF of 65.7% and 18 months later it was 123 sec−1(T2* 8.1 ms) with an LVEF of 72%. She developed significant arrhythmias coincident with her rapid cardiac iron loading. She was started on compassionate use deferiprone and deferoxamine, with which she is poorly compliant. Repeat cardiac MRI showed a worsening of cardiac iron with R2* of 204 sec−1 (T2* 4.9ms) after 8 months with an improved LVEF of 72%. She currently continues of her regular transfusions and deferiprone and is awaiting repeat MRI. Her LVEF improved while on the chelation therapy despite the deterioration in her cardiac iron content. This is consistent with our observation that LVEF tends to improve even with intermittent chelation although the cardiac iron may not decrease. Patient 3 died of numerous complications of SCD at the age of 19 years. She had started transfusions at the age of 10 years, because of a cerebrovascular accident. At the age of 14 years her first abdominal MRI demonstrated a LIC of 12.8 mg/g dw. She had her first cardiac MRI at the age of 16 years which showed no evidence of cardiac iron with a R2* of 30 sec−1 (T2* 32.7ms), which worsened to 57 (T2* 17.4ms) at the age of 17, reflecting a small but rapid increase in cardiac iron. Patient 1 and 2 demonstrate that transfusional iron overload can directly cause life threatening complications in patients with SCD. Patient 1 in particular, was in overt clinical heart failure that responded dramatically to intensification of chelation therapy. These data underscore the importance of direct measurement of tissue iron concentrations and points out that though uncommon, cardiac iron overload can occur in patients with sickle cell anemia with serious consequences. Disclosures: Berdoukas: ApoPharma Inc.: Consultancy. Carson:ApoPharma Inc.: Honoraria; Novartis Inc: Speakers Bureau. Wood:Cooleys Anemia Foundation: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Ferrokin Biosciences: Consultancy; Novartis: Research Funding. Coates:Novartis Inc: Speakers Bureau.

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