Multiparametric Cardiac Magnetic Resonance Survey in Children With Thalassemia Major: A Multicenter Study.

BACKGROUND: Cardiovascular magnetic resonance (CMR) plays a key role in the management of thalassemia major patients, but few data are available in pediatric population. This study aims at a retrospective multiparametric CMR assessment of myocardial iron overload, function, and fibrosis in a cohort of pediatric thalassemia major patients. METHODS AND RESULTS: We studied 107 pediatric thalassemia major patients (61 boys, median age 14.4 years). Myocardial and liver iron overload were measured by T2* multiecho technique. Atrial dimensions and biventricular function were quantified by cine images. Late gadolinium enhancement images were acquired to detect myocardial fibrosis. All scans were performed without sedation. The 21.4% of the patients showed a significant myocardial iron overload correlated with lower compliance to chelation therapy (P<0.013). Serum ferritin ≥2000 ng/mL and liver iron concentration ≥14 mg/g/dw were detected as the best threshold for predicting cardiac iron overload (P=0.001 and P<0.0001, respectively). A homogeneous pattern of myocardial iron overload was associated with a negative cardiac remodeling and significant higher liver iron concentration (P<0.0001). Myocardial fibrosis by late gadolinium enhancement was detected in 15.8% of the patients (youngest children 13 years old). It was correlated with significant lower heart T2* values (P=0.022) and negative cardiac remodeling indexes. A pathological magnetic resonance imaging liver iron concentration was found in the 77.6% of the patients. CONCLUSIONS: Cardiac damage detectable by a multiparametric CMR approach can occur early in thalassemia major patients. So, the first T2* CMR assessment should be performed as early as feasible without sedation to tailor the chelation treatment. Conversely, late gadolinium enhancement CMR should be postponed in the teenager age.

Low prevalence of cardiac siderosis in heavily iron loaded Egyptian thalassemia major patients.

Myocardial siderosis in thalassemia major remains the leading cause of death in developing countries. Once heart failure develops, the outlook is usually poor with precipitous deterioration and death. Cardiovascular magnetic resonance (CMR) can measure cardiac iron deposition directly using the magnetic relaxation time T2*. This allows earlier diagnosis and treatment and helps to reduce mortality from this cardiac affection. This study aims to determine the prevalence of cardiac siderosis in Egyptian patients who are heavily iron loaded and its relation to liver iron concentration, serum ferritin, and left ventricular ejection fraction. Eighty-nine ß-thalassemia patients receiving chelation therapy (mean age of 20.8 ± 6.4 years) were recruited in this study. Tissue iron levels were determined by CMR with cardiac T2* and liver R2*. The mean ± standard deviation (range) of cardiac T2* was 28.5 ± 11.7 ms (4.3 to 53.8 ms), the left ventricular ejection fraction (LVEF) was 67.7 ± 4.7 % (55 to 78 %), and the liver iron concentration (LIC) was 26.1 ± 13.4 mg Fe/g dry weight (dw) (1.5 to 56 mg Fe/g dw). The mean serum ferritin was 4,510 ± 2,847 ng/ml (533 to 22,360 ng/ml), and in 83.2 %, the serum ferritin was >2,500 ng/ml. The prevalence of myocardial siderosis (T2* of <20 ms) was 24.7 % (mean age 20.9 ± 7.5 years), with mean T2* of 12.7 ± 4.4 ms, mean LVEF of 68.6 ±5.8 %, mean LIC of 30.9 ± 13 mg Fe/g dw, and median serum ferritin of 4,996 ng/ml. There was no correlation between T2* and age, LVEF, LIC, and serum ferritin (P = 0.65, P = 0.085, P = 0.99, and P = 0.63, respectively). Severe cardiac siderosis (T2* of <10 ms) was present in 7.9 %, with a mean age of 18.4 ± 4.4 years. Although these patients had a mean T2* of 7.8 ± 1.7 ms, the LVEF was 65.1 ± 6.2 %, and only one patient had heart failure (T2* of 4.3 ms and LVEF of 55 %). LIC and serum ferritin results were 29.8 ± 17.0 mg/g and 7,200 ± 6,950 ng/ml, respectively. In this group of severe cardiac siderosis, T2* was also not correlated to age (P = 0.5), LVEF (P = 0.14), LIC (P = 0.97), or serum ferritin (P = 0.82). There was a low prevalence of myocardial siderosis in the Egyptian thalassemia patients in spite of very high serum ferritin and high LIC. T2* is the best test that can identify at-risk patients who can be managed with optimization of their chelation therapy. The possibility of a genetic component for the resistance to cardiac iron loading in our population should be considered.

Predicted costs of iron-chelators in myelodysplastic syndromes: a 10-year analysis based on actual prevalence and red cell transfusion rates.

Consideration of iron-chelation (IC) in transfusion-dependent patients is recommended in most clinical-practice guidelines on myelodysplastic syndromes (MDS). The financial impact of IC on health-care systems is predicted through economic modeling, but an analysis based on actual prevalence is lacking. Here, we have investigated the potential drug-costs and need for IC in a cohort of 189 United Kingdom-based MDS patients diagnosed from 2000 to 2010. Patients with low or intermediate-1 IPSS scores were identified as eligible for IC if ≥24 red cell units (RCU) had been transfused over 12 consecutive months or the transfusion-intensity averaged ≥2 RCU per month. Drug-costs were calculated from the time patients qualified for IC until death or last follow-up. In 159 patients with low/intermediate-1 MDS, survival was superior with a low IPSS score (P = 0.014), age <70 years (P = 0.043), transfusion-independence at diagnosis (P = 0.0056) and transfusion-intensity of <2 RCU per month (P = 0.009). Reflecting the time elapsed since diagnosis, longer survival was observed with a cumulative red cell load of ≥75 U (P = 0.046). By logistic-regression analysis, transfusion-intensity independently predicted survival (P = 0.0035) in low and intermediate-1 risk MDS patients. Forty-one patients fulfilled criteria for consideration of IC. Of these, 6 patients died within 1 month; 35 patients survived for a median of 16 months (range 1-61). Had patients commenced IC, the anticipated drug-costs alone would have been ~$526,880-$2,064,800 over 10 years. The lack of association between cumulative transfusion-load and survival calls for a prospective evaluation of the cost-utility of IC in patients surviving long-term, to enable evidence-based recommendations in MDS management.

Grape seed extract alleviates high-fat diet-induced obesity and heart dysfunction by preventing cardiac siderosis.

Obesity is a tremendous public health problem, characterized by ectopic accumulation of fat into non-adipose tissues, leading to oxidative stress and chronic inflammation, in which the heart is the most severely affected organ. We used an experimental model of high-fat-diet (HFD)-induced obesity to analyze the link between oxidative stress and heart dysfunction. We also studied the cardioprotective effect of a grape seed and skin extract (GSE). Exposure of rats to HFD during 45 days induced heart hypertrophy, inflammation as assessed by plasma CRP elevation and contractile dysfunction as revealed after ischemia/reperfusion of Langendorff-perfused hearts. HFD also induced cardiac steatosis and lipotoxicity, which are linked to an oxidative stress status, worsened by increased siderosis and resulting in Ca(2+) overload. Importantly, GSE alleviated all the deleterious effects of HFD treatment. These studies suggest that GSE is a safe anti-obesity and cardioprotective agent that should also find potential applications in other inflammatory damaging conditions as stroke.

Transfusional hemosiderosis and combined chelation therapy in sickle thalassemia.

Although the indications for transfusions in sickle cell syndromes are well listed, and chronic transfusion has become practicable since the recent advances in chelation therapy have essentially eliminated the risk of secondary iron overload, multi-transfused, non-compliant to long-term chelation therapy patients confront the complication of iron overload and secondary hemosiderosis. In thalassemia major patients, combined therapy with desferrioxamine and deferiprone has maximized tissue iron removal and may reduce the overall occurrence of hemosiderotic heart failure. Despite this, safety and contradictions of chelating agents are still controversial. The aim of this report is to present the results of this combination in a long-term transfused sickle beta-thalassemic patient suffering from severe heart failure and liver dysfunction.

Effective use of tea to limit dietary iron available to starlings (Sturnus vulgaris).

Wild-caught starlings (Sturnus vulgaris) were fed an iron-enriched diet, with or without supplemental black tea leaves, to determine whether tea-derived tannins would prevent intestinal iron absorption. Hepatic biopsies were obtained to determine hepatic iron concentrations by atomic absorption spectroscopy. Hepatic iron concentrations increased significantly (P = 0.04) in 21 birds that consumed only the iron-enriched diet for 6 mo but not in the 20 birds that consumed the iron-enriched diet with tea leaf supplementation for the same time period.

Pancreatic sonography in thalassemia major.

Four patients with thalassemia major and well documented transfusional anamnesis were investigated sonographically. Beside the fibrous reaction of iron overload in the liver the outstanding finding was the grossly increased echogenicity of the normal sized fibrotic pancreas in transfusional hemosiderosis. Upper abdominal sonography may be an useful - noninvasive - method for the assessment of iron load in regularly transfused patients. Moreover, pancreatic sonography may be helpful as follow-up method of chelation therapy.

Effect of subcutaneous deferoxamine and oral vitamin C on iron excretion in congenital hypoplastic anemia and refractory anemia associated with the 5q-syndrome.

Chronic refractory anemia associated with congenital hypoplastic anemia (CHA, Blackfan-Diamond syndrome) and with the 5q-syndrome may require chronic transfusion therapy to sustain life. Hemosiderosis and death from chronic iron overload may result from such a program. The effect of subcutaneous (SC) deferoxamine (DF) and supplemental oral vitamin C (vit. C) on urinary iron excretion was studied in two patients with congenital hypoplastic anemia and one patient with 5q-syndrome. In the two patients with CHA, urinary iron excretion in response to DF given SC over 24 hours was comparable to the results following intravenous (I.V.) administration. Both of these cases had low levels of plasma ascorbate on initial evaluation and excreted more iron in response to two different doses of DF after they had received supplemental vit C and their stores were repleted. Significant iron excretion occurred in all three patients for 12 hours during the SC infusion of DF and for 12 hours after the end of the infusion. In all three patients, increasing the dose of DF up to 3-4 g given SC over 12 hours resulted in a linear increase in iron excretion. Once normal body stores of ascorbate were achieved by oral supplementation, increasing doses of vit C did not appear to cause a further increment in iron excretion. DF administered by a slow SC infusion appears to be an effective approach to iron overload in patients with refractory anemia and hemosiderosis secondary to chronic transfusions. Only small amounts of supplemental vit. C necessary to sustain adequate body stores are required for optimal iron excretion.

Intravenous and subcutaneous desferrioxamine therapy in children with severe iron overload.

Ten children with transfusion dependent anemias (thalassemia, sideroblastic anemia, congenital pure red cell aplasia) received either intravenous desferrioxamine (DF) in increasing doses up to 450 mg/kg at the time of transfusion or daily subcutaneous DF up to 110 mg/kg on an outpatient basis. No patient on intravenous DF reached a negative iron balance. All children with a subcutaneous DF dose of more than 60 mg/kg obtained a negative iron balance with a net iron excretion (transfusion iron already substracted) between 206 to 810 mg (mean 496 mg) monthly. The effectiveness of regular subcutaneous DF on liver storage iron could be confirmed in 4 patients by liver biopsy, showing a decrease between 40-60% iron after 12-14 months of chelation therapy. So far the daily iron excretion has remained constant with a given dose of DF over a period up to 15 months. Even if poor compliance in some patients is taken into account, it is possible with this method of treatment to prevent further accumulation of iron in chronically transfused children.