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Reversal of Cardiac Failure in Thalassemia Dr Khawla Belhoul Director Thalassemia Center Interdepartmental meeting November 2008 Cardiomyopathy kills young patients with Thalassemia Heart failure is the leading cause of death in patients with ß-thalassemia major 60%mortality Iron cardiomyopathy is preventable is treatable is reversible Multifactorial aetiology of heart failure in Thalassemia patients – Iron overload – Chronic haemolysis – High cardiac output state – Tissue hypoxia. – Endocrine deficiencies. – Metabolic deficiencies – Myocarditis. – Immunogenic. – Genetic : the ApoE 4 allele Iron Cardiomyopathy Causes of Iron Overload – Transfusion related. – Iron hyperabsorption and maldistribution. – tissue hypoxia ->reduction of hepcidin levels > leads to iron hyperabsorption and maldistribution. – urinary hepcidin was found to be suppressed in TM and TI patients. – down-regulation of hepcidin is proportional to the increase of erythropoietic activity. Iron Cardiomyopathy • Is a restrictive cardiomyopathy that manifests itself as systolic or diastolic dysfunction. • Iron induced oxidative. • Iron induced cardiac fibrosis (Angiotensin II). Chronic Hemolysis Oxidative Stress free heme and the RBC membrane elements A nitric oxide and arginine vasoconstriction. endothelial dysfunction, Other endocrine comorbidities • Hypoparathyroidism can produce hypocalcaemia cardiomyopathy • Severe growth hormone deficiency is associated with cardiomyopathy • Adequate thyroid hormone levels are vital for cardiac function • Good glycemic control lowers oxidative stress Nutritional comorbidities • Carnitine – Single –arm studies suggest improved cardiac systolic/diastolic function • B complex vitamines – Severe deficiency in B1 ,B6 are common – Role in heart failure is unknown. • Vitamin D deficiency – Correlated with cardiac dysfunction /CHF in non thalassaemic cardiac and renal failure patients – Correlated with LVEF in TM • Selenium, zinc?? Multifactorial aetiology of heart failure in Thalassemia patients – Iron overload – Chronic haemolysis – High cardiac output state – Tissue hypoxia. – Endocrine deficiencies. – Metabolic deficiencies – Myocarditis. – Immunogenic. – Genetic : the ApoE 4 allele We are no more powerless to predict WHO is at risk ?? MRI T2* MRI T2* • MRI remains the only non-invasive modality in clinical use with the ability to detect cardiac iron deposition. • Reductions in cardiac iron assessed by MRI correlate with improvements in cardiac function . • In general, the lower the T2* the higher the risk of cardiac dysfunction. • T2* <8 ms suggestive of severe iron overload • MRI T2* is has improved our ability to detect those patients at risk. • MRI T2* has allowed us to compare the cardiac benefits of different Chelation regimens. T2* - CARDIAC RISK RANGING Below a myocardial T2* of 20 ms, there was a progressive and significant decline in LVEF ( P<0·0001) High Intermediate Low HEART T2* IN INCIDENT HEART FAILURE 8 Mean=6.7 +/- 2.4ms 7 n=28 Frequency 6 89% <10ms 5 4 3 2 1 0 2-3 3-4 4-5 5-6 6-7 7-8 8-9 9-10 10-11 11-12 12-13 Heart T2* (ms) All patients T2* >20ms no heart failure, unless congenital heart disease All patients T2* >20ms no heart failure, unless congenital heart disease Reference: Tanner M. ASH Abstracts 2005 Iron cardiomyopathy is preventable is treatable is reversible What is the ideal iron chelator ? The ideal iron chelator DEFERIPRONE INDUCED AGRANULOCYTOSIS • Agranulocytosis remains the major concern for patients receiving deferiprone. • occurs in less than 1% of patients who undergo weekly monitoring of their blood counts . • Milder neutropenia (500–1500/mm3) occurs in about 8% of patients. DEFERIPRONE INDUCED AGRANULOCYTOSIS Three important questions about deferiprone and agranulocytosis remain incompletely answered. – First, does the currently recommended weekly monitoring of blood counts during deferiprone therapy reduce the risk of agranulocytosis ? – Second, should weekly monitoring continue indefinitely? – Third, should patients who develop agranulocytosis be re-treated with deferiprone after their neutrophil counts return to normal? DEFEROXAMINE IN HEART FAILURE • 7 patients presenting with heart failure • All patients given IV deferoxamine for 12 months • CMR of T2* and LV function at 0, 3, 6, and 12 months Reference: Anderson LJ. Br J Haematol 2004;127:348 MYOCARDIAL T2* REPRODUCIBILITY IN TRIAL • 1 patient died – Liver iron 4.1 mg/g dry weight – Myocardial iron 5.9 ms (normal >20 ms) • 6 survivors Reference: Anderson LJ. Br J Haematol 2004;127:348 REVERSAL OF MYOCARDIAL SIDEROSIS T2* ms T2* ms n=6, p=0.003 n=6, p=0.003 Reference: Anderson LJ. Br J Haematol 2004;127:348 CONCOMITANT IMPROVED LV FUNCTION n=6 p=0.03 p=0.02 p=0.02 p=0.03 Reference: Anderson LJ. Br J Haematol 2004;127:348 LA16: MYOCARDIAL T2* Deferiprone Deferoxamine p=0.77 p=0.040 Reference: Pennell DJ et al. Blood 2005 e-pub December 22nd p=0.023 DEFEROXAMINE ALONE VS COMBINATION Rx T2* P<0.001 Combined P=0.074 Heart Deferoxamine Liver Reference: Tanner MA. ASH 2005 abstracts Between groups p=0.017 Management acute congestive Cardiac failure in Thalassemia patients • Try to exclude viral myocarditis and thyroid disorders. Look for history of chest pain and/or flue like. • Perform FBC,U&E,CA, CR, CRP,ESR , autoimmune screen, cardiac enzymes ,T3,T4 ,TSH, ECG, Thrombophilia screen, Echo & • T2* MRI once stable ;if not done recently Management acute congestive Cardiac failure in Thalassemia patients • Conventional heart failure treatment • Give hydrocortisone : under stress these patients are likely to require steroid supplements due to occult adrenal insufficiency. • Once hemodynamically stable start continuous infusion of DFO (Deferoxamine) 40 mg/kg/day. • On day 6 of chelation and if the patient condition is stable add Deferiprone 75 mg/kg/day p.o. • Continue the iv chelation for at least 10days. • Day 11 of chelation shift to subcutaneous DFO 50 mg/kg/day . Continue oral Deferiprone. • day 21 increase Deferiprone dose to 100mg/kg/day and continue Desferal as before . • Keep hemoglobin levels > 9 g/dL. Precautions with parenteral administration of Desferal: • Desferal should be prepared as a 10% solution in water for injections.( 5 mL water+ 500 mg Desferal powder). • The 10% Desferal solution to be further diluted with (sodium chloride, glucose, Ringer's solution). • Rates of infusion should not exceed 15 mg/kg/hr. • Always start Intravenous Desferal slowly as fast initial infusions may lead to severe hypotension and shock (e.g. flushing, tachycardia, urticaria and collapse). Transfusion protocol adjustment for Thalassemia Patients Who Have Cardiac Problem: • Pre transfusion Hb >9.5 g/dl • PRBC transfusion rate 2ml/kg/hr • Give prophylactic Frusemide 20 mg IV if pre Hb level <7 g/dl Risk factors modifications • Hypertension • Serum lipid • Optimizing body weight • Smoking cessation • Alcohol abstinence • Control of blood sugar TREATMENT OF ESTABLISHED CARDIOMYPATHY • Arrhythmias respond more quickly to chelation than cardiac function . • Amiodarone is the drug of choice • Catheter ablation is contraindicated. • ICD’s should be avoided unless there is documented arrhythmia-associated syncope or aborted sudden death. • Treat aggressively and don’t give up early. • Consider even cardiac transplantion if necessary. TREATMENT OF ESTABLISHED CARDIOMYPATHY • Aggressive Chelation; aggressive Chelation • Correction of endocrine deficiencies • Correction of metabolic deficiencies • Arrthymia control • Convential heart failure medications • No blame environment • Start by blaming yourself • Accept open criticism and difficult arguments and discussions it creates strong environment and people • Family environment and team work comes only if you keep sensitivity at home. • Change can start down and propagate to higher authority .