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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cardiac disease remains the major cause of death in thalassaemia major. This review deals with the mechanisms involved in heart failure development, the peculiar clinical presentation of congestive heart failure and provides guidelines for diagnosis and management of the acute phase of cardiac failure. It emphasizes the need for intensive medical--cardiac care and aggressive iron chelating management as, with such approaches, today, the patients outcomes can be favourable in the long term. It covers advances in the assessment of cardiac iron overload with the use of magnetic resonance imaging and makes recommendations for preventing the onset of cardiac problems by tailoring iron chelation therapy appropriate to the degree of cardiac iron loading found.
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PMID:The heart in transfusion dependent homozygous thalassaemia today--prediction, prevention and management. 1808 19

Cardiac damage caused by iron overload toxicity is the main cause of death in thalassemia patients. Biopsy samples of poorly chelated thalassemia patients who suffered congestive cardiac failure (CCF) show extensive iron deposition in the myocardium. In one patient who survived CCF, a cardiac biopsy was performed during the removal of a thrombus caused by a port-a-cath, which was used for the administration of intravenous (iv) deferoxamine (DFO). Ultrastructural pathology studies of the cardiac biopsy indicated extensive iron deposition in myocytes with accumulation of iron mainly in lysosomes, leading in some cases to their disruption. Damage to other intracellular components of the myocytes and loss of myofibers was also observed. The patient became intolerant to iv and subcutaneous (sc) DFO 2 years after the CCF, and was then treated with deferiprone (L1) for 7 years. Within 1 year of L1 treatment at 75-80 mg/kg/day, serum ferritin levels were reduced to <0.45 mg/L and she became asymptomatic, needing no further drugs for her cardiomyopathy. Lowering the L1 dose to 50-70 mg/kg/day caused an increase in serum ferritin levels. Maintenance of normal iron stores during the last 3 years as detected by cardiac and liver magnetic resonance imaging (MRI) T2 and T2* and normalization of serum ferritin levels (<0.15 mg/L) was observed following L1 therapy at 80-85 mg/kg/day. Deferiprone (>80 mg/kg/day) appears to be effective in the rapid clearance of cardiac iron, in the reversal of iron overload related cardiomyopathy, in the maintenance of normal iron stores and the overall long-term survival of thalassemia patients.
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PMID:Myocyte damage and loss of myofibers is the potential mechanism of iron overload toxicity in congestive cardiac failure in thalassemia. Complete reversal of the cardiomyopathy and normalization of iron load by deferiprone. 1827 79

The iron chelators deferoxamine (DFO) and deferiprone (L1) have demonstrated their ability to normalize cardiac function in patients with iron overload-induced cardiac disease. However, conventional chelation with subcutaneous DFO fails to prevent iron deposition in two-thirds of thalassemia major patients, placing them at risk of heart failure and its complications. Deferiprone appears to be more effective in cardiac iron removal. The detection and management of heart complications have improved dramatically over the last 7 years. Non invasive techniques of quantifying iron burden via magnetic resonance imaging (MRI) have been validated. A better understanding of cardiac pathophysiology and improved ability to detect at-risk populations are yielding better outcomes and reduced morbidity. We continue to appraise readily available bedside tools for monitoring thalassemia patients with heart complications, and here we summarize studies from the literature and our own findings. Deferiprone chelation was found to be of statistically significant benefit in upgrading cardiac function and reducing iron accumulation. The use of echocardiography and MRI to closely monitor cardiac functions associated with iron overload complications and mortality has proved quite practical.
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PMID:Effects of chelation therapy on cardiac function improvement in thalassemia patients: literature review and the Taiwanese experience. 1827 83

Hypocalcemia due to hypoparathyroidism (HPT) is a late complication of iron-overloaded patients with b-thalassaemia major (TM). The majority of patients have mild disease with parasthesias, while in the more severe form tetany, seizures or cardiac failure may occur. In the last 20 years we observed heart failure in 2 out of 38 (5.2%) TM patients (aged 18 and 22 years) with hypocalcemia secondary to HPT associated to iron overload. Calcium supplementation and vitamin D induced correction of hypocalcemia and resulted in an improvement of cardiac function. Calcium plays a key role in the maintenance and regulation of normal cardiac function. Extra-cellular calcium is indispensable for the contractile process since the sarcoplasmatic reticulum is unable to maintain a sufficient amount of calcium to trigger myocardial contraction. In conclusion, our observations stress the importance of a regular iron chelation therapy, adherence to treatment of endocrine complication and regular follow-up of TM patients with hypocalcemia.
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PMID:A rare cause of heart failure in iron-overload thalassaemic patients-primary hypoparathyroidism. 1840 23

Thalassemia is an inherited blood disorder due to an imbalanced globin chain synthesis leading to anaemia that requires regular blood transfusions and iron-chelating therapy. Of all organ failures secondary to iron deposit, and all the complications, heart failure still represents the first cause of death. Osteopenia and osteoporosis can be considered important causes of morbidity in a population whose lifespan is getting longer, with a strong impact on their quality of life. Authors have reported mainly bone, oral and maxillofacial abnormalities and relative complications, especially in terms of traumatic risk, in patients affected by thalassemia. As examples, this study reports bone modifications in three clinical cases; one of these was also complicated with a femoral fracture, surgically treated with the same criteria of metastatic femoral bone disease. More research on this topic is necessary for the prevention of several complications caused by this disease, and to carefully plan dental or traumatologic operations.
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PMID:Bone and maxillofacial abnormalities in thalassemia: a review of the literature. 1903 22

Cardiovascular involvement is a leading cause of mortality and morbidity in patients with inherited hemoglobinopathies, but it has not been adequately assessed in sickle beta-thalassemia. We evaluated 115 sickle beta-thalassemia patients, aged 34 +/- 14 years, along with 50 healthy controls, by resting echocardiography. Patients with systolic left ventricular (LV) dysfunction or severe pulmonary hypertension (PHT) also underwent left and right cardiac catheterization and cardiac magnetic resonance imaging (CMR). Left and right chamber dimensions, LV mass, and cardiac index were significantly higher in patients compared to controls (p < 0.001 in most cases). Three patients (2.9%) had reduced LV ejection fraction (<55%); mean LV ejection fraction was significantly lower in patients (p < 0.001). Left and right ventricular systolic tissue Doppler indices and LV diastolic tissue Doppler indices were also impaired in patients. All three patients with systolic LV dysfunction had normal coronary arteries and mild myocardial iron load (CMR T2* values, 18-25 ms). Systolic pulmonary artery pressure was significantly higher in patients compared to controls (p = 0.002); PHT was present in 28 patients (27%), while severe PHT in three (2.9%). In three patients with severe PHT, only one had impaired LV ejection fraction and increased pulmonary wedge pressure. Overall, three patients (2.9%) had a history of heart failure, two with systolic LV dysfunction, and one with severe PHT. Cardiac involvement in sickle beta-thalassemia concerns biventricular dilatation and dysfunction along with PHT, leading to congestive heart failure.
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PMID:Cardiac involvement in sickle beta-thalassemia. 1910 83

Data concerning electrocardiographic (ECG) abnormalities in thalassemic cardiomyopathy are scanty. Current techniques to detect early findings of myocardial involvement in thalassemia (Magnetic Resonance, Stress Echo, Tissue Doppler Imaging) are not widely available. We sought to determine whether new ECG abnormalities emerge in thalassemia patients when heart failure due to cardiomyopathy occurs. ECG and Echo Doppler examinations of 28 consecutive adult thalassemia patients with heart failure observed at our hospital were compared with ECG and Echo Doppler examinations performed before the onset of heart dysfunction and with those of 60 age and sex-matched patients with thalassemia without evidence of cardiac involvement. All the patients with heart failure had new ECG abnormalities. New onset supraventricular arrhythmias, T wave inversion, low voltages, right QRS axis deviation and S1Q3 pattern developed respectively in 46%, 79%, 43%, 18% and 15% of thalassemic patients with heart failure. None of the patients without heart failure showed any ECG abnormality (P<0.001). In conclusion this study suggests that new onset ECG abnormalities are always evident in patients with and always absent in patients without heart failure due to thalassemic cardiomyopathy.
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PMID:Electrocardiographic abnormalities in thalassemia patients with heart failure. 1927 75

From 1990 to 1991, the Pediatric and Adolescent Endocrine Outpatient Clinic of Arcispedale S. Anna admitted 97 thalassaemia major (TM) patients for endocrine evaluation. Their mean age was 14.2+/-5.7 years (range 5-28 years). Sixty-eight (70%) had normal thyroid function and twenty-one (21.6%) were discharged with a diagnosis of hypothyroidism of different degrees of severity. Thirteen patients out of 21 (61.9%) were females. Twelve patients (57.1%) fulfilled the criteria for subclinical hypothyroidism (SH). Their mean age was 15.7+/-3.5 years (range 9-22 years). A positive direct correlation was observed between the following variables: TSH and serum ferritin, TG and basal TSH, basal TSH and peak levels after TRH stimulation test. In 6 out of 12 TM patients (50%) with SH type a, the basal ejection fraction assessed by MUGA scan was normal; 1 TM patient (8.3%) showed mild abnormality and 5 TM patients (41.6%) showed severe abnormalities. A normal response during exercise (increase in LVEF greater than 5 percentage units) occurred in 10 patients (83.3%). Global or segmental left ventricular dysfunction at rest and during exercise were found in 8 patients (66.6%) and 10 patients (83.3%), respectively. These cardiac abnormalities were more common in TM patients with severe iron overload and poor compliance to DFX treatment (group A: serum ferritin above 2500 ng/ml) compared to TM patients with mild-moderate iron overload (group B: serum ferritin below 2500 ng/ml). In the control group of TM patients (group C) with normal thyroid function the assessment of MUGA scan was normal in all subjects at rest and after exercise. Global or segmental left ventricular dysfunction was observed only during exercise in 50% of TM patients with normal thyroid function (group C). Our patients with SH exhibited three different thyroid function patterns during follow-up: a. 3 (25%) of 12 studied TM patients showed a normalization of serum TSH levels b. 2 patients (16.6%) showed intermittent elevation of serum TSH with normal serum FT4 concentrations c. 3 patients (25%) had a persistent mild elevation of serum TSH concentration (from 6.3 to 7.6 microU/ml) with serum FT4 concentrations within the normal range. Two TM patients (16.6%) were treated with L-thyroxine. The reason for starting therapy was an abnormality of basal LVEF in the presence of mild iron overload (serum ferritin levels 665 ng/ml and 523 ng/ml). One TM patient with persistent SH type a developed a papillary carcinoma, and another, a multinodular goiter. The serum ferritin levels at diagnosis were 4739 ng/ml and 744 ng/ml,respectively. The thyroid function in TM patients from group C remained normal during the follow-up period. Two patients (Group A: patients no. 1 and 2) with severe iron overload and poor compliance to chelation therapy died during the follow-up, due to heart failure and arrhythmia. The time intervals between the first abnormal LVEF value and the development of symptomatic heart failure were 3.8 and 4.3 years. An improvement of LVEF was observed in three TM patients from group A after 24 months of intensive subcutaneous chelation therapy with DFX, and in two patients from Group B after 12-14 months of L-thyroxine replacement therapy in association with regular iron chelation therapy. In those two TM patients the basal LVEF increased from 37% to 45% and from 45% to 49%. In conclusion, although the findings are limited to a small group of TM patients with SH type a, our results show a high prevalence of primary hypothyroidism with the predominance of its mildest form, its stable course over years in most patients, and the presence of cardiac involvement in patients with severe-moderate iron overload. Regular iron chelation therapy should be advised for these patients to prevent thyroid dysfunction and the development of clinically significant myocardial dysfunction. In addition, therapy with L-thyroxine should be considered in iron overloaded TM patients with SH and a poor response to chelation therapy and in patients with SH and mild iron overload.
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PMID:Mild subclinical hypothyroidism in thalassaemia major: prevalence, multigated radionuclide test, clinical and laboratory long-term follow-up study. 1933 74

In b-thalassemia, myocardial iron overload contributes to heart failure, despite chelation treatment. We hypothesized that myocardial T2*, an index of iron overload, influences patients' physical activity. We assessed a thalassemic population by both cardiovascular magnetic resonance imaging (CMR) and ergospirometry test. Sixty-six thalassemic patients aged 27 (19-40) years, 30 without (NHF) and 36 with heart failure (HF), were studied. Cardiac T2* and left ventricular ejection fraction (LVEF) were evaluated using a 1.5 T system. VO(2max), AT, Mets and duration of exercise by ergospirometry were also assessed. Myocardial T2* was lower in HF compared to NHF patients (14.7 +/- 6.6 vs. 39 +/- 2 ms, P < 0.001). LVEDV and LVESV were higher in HF group compared to NHF patients (139.9 +/- 16.3 vs. 124.6 +/- 20.86 ml, P < 0.01 and 94.9 +/- 24 vs. 38.3 +/- 10.1 ml, P < 0.001, respectively). Additionally, LVEF in HF was lower compared to NHF patients (21.3 +/- 6.1% vs. 69.6 +/- 3.7, P < 0.001, respectively). All exercise parameters were lower in HF compared to NHF patients (P < 0.001). Patients within the HF group were additionally analyzed according to T2* values (<10 ms). HF patients with T2* < 10 ms (n = 13) were considered as high iron overloaded (HF-H) and the rest of them (n = 23) as (HF-L). Although LVEDV, LVESV, LVEF were similar in the two subgroups, the exercise parameters were significantly lower in the HF-H group (P < 0.001). Heart T2* correlated with all exercise parameters (P < 0.001). HF thalassemic patients have reduced exercise indexes compared to non HF. Myocardial iron overload, expressed as T2*, has a direct influence on exercise capacity, independent of LV ejection fraction and functional class.
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PMID:Effect of iron overload on exercise capacity in thalassemic patients with heart failure. 1993 25

We present a 57-year old male patient with thalassemia intermedia and right heart failure. He had a 30-year history of anemia and short-term iron therapy without blood transfusion. Hemoglobin level was 7.1 g/dl and hematocrit was 22.7%. White blood-cell and platelet counts, and serum ferritin level were normal. Electrocardiography showed irregular narrow QRS bradyarrhythmia, suggesting slow atrial fibrillation at a mean rate of 35 beats/min. Echocardiographic examination revealed dilatation of the right atrium and ventricle, depressed systolic right ventricular function, advanced tricuspid regurgitation, and mild pericardial effusion. In the electrophysiologic study, no electrical activity was recorded in the right atrium. It was inexcitable at multiple sites and no retrograde conduction to the right atrium could be elicited by ventricular pacing. His bundle (HB) recording showed fixed retrograde HB activation with ventricular rhythm originating from different foci. Retrograde V-H conduction time during ventricular rhythm was 95 msec and did not change. There was no retrograde nodal conduction. A VVIR pacemaker was implanted. During a six-month follow-up, he felt well, his functional capacity was NYHA class II, and his basic rhythm was widened QRS arrhythmia with a rate of 20 beats/min. To the best of our knowledge, atrial electrical inactivity together with right-heart failure and pericarditis confined to the right heart chambers has hitherto not been reported in thalassemic disorders.
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PMID:Persistent atrial standstill and idioventricular rhythm in a patient with thalassemia intermedia. 1971 59


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