Marcadores eletrocardiográficos para detecção precoce de doença cardíaca em pacientes com talassemia beta maior / Electrocardiographic markers for the early detection of cardiac disease in patients with beta-thalassemia major

OBJETIVO: Analisar comparativamente a dispersão da onda P (DOP) em pacientes com talassemia beta maior (β-TM) e indivíduos saudáveis (controles) para a detecção precoce do risco de arritmias. MÉTODOS: Oitenta e uma crianças com β-TM, com idades entre 4 e 19 anos, e 74 crianças saudáveis (grupo controle) foram submetidas a exame eletrocardiográfico e ecocardiograma transtorácico de rotina para avaliação cardíaca. A DOP foi calculada como a diferença entre as durações máxima e mínima da onda P. RESULTADOS: Houve uma diferença estatisticamente significativa entre o grupo de estudo e o grupo controle no pico de velocidade do fluxo transmitral no início da diástole (E) e na razão E/fluxo transmitral tardio (A). A duração máxima da onda P e a DOP foram significativamente maiores nos pacientes com β-TM do que nos indivíduos controles. CONCLUSÕES: O aumento da DOP em nossos pacientes com β-TM pode estar relacionado à depressão na condução intra-atrial, devido à dilatação atrial, e ao aumento da atividade simpática. Estes pacientes devem ser acompanhados atentamente devido à possibilidade de ocorrência de arritmias com risco de vida.

OBJECTIVE: To comparatively evaluate P-wave dispersion (PWD) in patients with β-thalassemia major (TM) and healthy control subjects for the early prediction of arrhythmia risk. METHODS: Eighty-one children with β-TM, aged 4-19 years, and 74 healthy children (control group) underwent routine electrocardiography and transthoracic echocardiography for cardiac evaluation. PWD was calculated as the difference between the maximum and the minimum P-wave duration. RESULTS: There was a statistically significant difference between study and control groups in peak early (E) mitral inflow velocity and E/late (A) velocity ratio. Maximum P-wave duration and PWD were found to be significantly higher in β-TM patients than in control subjects. CONCLUSIONS: Increased PWD in our β-TM patients might be related to depression of intra-atrial conduction due to atrial dilatation and increased sympathetic activity. These patients should be closely followed up for risk of life-threatening arrhythmias.

Shunt operations improved thrombocytopenia in a patient with congenital cyanotic heart disease.

Cardiac and vascular intervention in thrombocytopenic congenitally cyanotic patients is more dangerous. Thrombocytopenia in these patients is related to immune thrombocytopenia, polycythemia, hyperviscosity, pseudothrombocytopenia, and drugs. Herein we report on a thrombocytopenic 8-year-old girl with tricuspid valve atresia and pulmonary valve stenosis admitted for catheterization. Thrombocytopenia (21,000/mm3) and shunt occlusion was noticed. Thrombocytopenia did not recover after intravenous immunoglobulin (IVIG) and phlebotomy therapies. During preparation for surgery, she suffered cardiopulmonary arrest. A Gore-tex graft was placed in the right pulmonary artery and truncus brachiocephalicus. After surgery, her platelet count spontaneously increased to within the normal range (178,000/mm3 to 250,000/mm3). After resuscitation, she had right-sided hemiplegia sequelae, though there were no hemorrhagic findings on cranial magnetic resonance imaging (MRI) or computed tomography (CT) scans. Two months after surgery, the Blalock-Taussig (BT) shunt blood flow decreased, thrombocyte count dropped, and peripheral cyanosis reappeared. A Fontan operation was performed without hemorrhagic events, and after surgery the thrombocyte count reached 330,000/mm3. We suggest that if a patient with cyanotic heart disease has thrombocytopenia and there is no apparent cause, hypoxia-related thrombocytopenia must be considered. After reoxygenation by shunt or corrective surgeries, thrombocyte count and functions will recover.

Congenital heart disease in children with Down's syndrome: Turkish experience of 13 years.

BACKGROUND: Down's syndrome (DS) is the most common chromosomal abnormality due to a trisomy of chromosome 21 commonly associated with congenital heart defects (CHDs). This study aimed to evaluate the frequency and types of CHD patterns in Turkish children with DS. METHOD: The data relate to paediatric patients with DS who underwent cardiologic screening between 1994 and 2007 and were reviewed in our Paediatric Cardiology unit. RESULTS: Four hundred and twenty-one out of the 1042 paediatric patients with DS studied over a 13-year period had associated CHD. Of these, 320 (77.6%) had a single cardiac lesion, while the remaining 92 patients (22.4%) had multiple defects. The most common single defect was an atrioventricular septal defect (AVSD) found in 141 patients (34.2%), followed by 69 patients (16.7%) showing secundum type atrial septal defect, and ventricular septal defect in 68 patients (16.5%). AVSDs were the leading type, isolated or combined with other cardiac anomalies with an overall occurrence of 19.8% of paediatric patients with DS, and 49.2% of paediatric patients with both DS and CHD. CONCLUSION: This is the first study concerning the frequency and type of CHD observed in Turkish children with DS. The high frequency of AVSD in Turkish children with DS implied that early screening for CHDs by echocardiography is crucial. The correction of AVSDs in paediatric patients with DS should be performed in the first 6 months of life to avoid irreversible haemodynamic consequences of the defect.

The effects of surgical repair on P-wave dispersion in children with secundum atrial septal defect.

INTRODUCTION: Atrial septal defect (ASD) is one of the most common congenital heart diseases in children. P-wave dispersion has been reported to be associated with non-homogeneous propagation of sinus impulses. The heterogeneity of atrial conduction time may predispose the atria to arrhythmias. The aim of this study was to determine the impact of surgical repair on P-wave indices in children with isolated secundum ASD. METHODS: Children with isolated secundum ASD undergoing surgical repair (n=50; mean age, 7.0+/-3.0 years) and healthy controls (n=51; mean age, 7.6+/-2.7 years) were compared. Maximum P-wave duration (Pmax), shortest duration (Pmin) and P-wave dispersion (Pd) were measured using 12-lead surface electrocardiography. RESULTS: Mean Pmax was found to be significantly higher in children with ASD compared with controls (95.2+/-10.8 vs 84.1+/-9.2 msec; P<0.001), and Pd before surgery was significantly higher compared with controls (47.4+/-12.0 vs 38.8+/-9.7 msec; P<0.001). Both P-wave indices were significantly decreased within the first year after surgical closure - the values decreased to those comparable to healthy controls (Pmax, 86.2+/-9.7 msec; Pd, 39.8+/-10.7 msec; P>0.05). CONCLUSION: Surgical closure of ASD in children decreases Pmax and P-wave conduction time. We speculate that earlier closure of the defect may play an important role in avoiding permanent changes in the atrial myocardium and atrial fibrillation in adulthood.

Does red-man reaction stimulate macrophage activation syndrome in children with systemic juvenile idiopathic arthritis?

Macrophage activation syndrome (MAS) is a major cause of death in patients with systemic juvenile idiopathic arthritis (JIA). We describe 4 patients who developed MAS during or after vancomycin treatment. Vancomycin should be used with great care in patients with systemic JIA.

Fish oil supplementation improves left ventricular function in children with idiopathic dilated cardiomyopathy.

Fish oil has a cardioprotective effect in adults with ischemic heart disease. The authors examined the effects of fish oil in children with idiopathic dilated cardiomyopathy (DCM). Eighteen DCM patients (group I) and 12 healthy children (group III) were given fish oil (10 mL/d). Their cardiac findings were compared with those of 11 patients with DCM who did not receive fish oil (group II). After 6.62+/-1.70 months, left ventricular ejection fraction had increased by 8.44%+/-3.80% (P<.05), in group I; 2.48%+/-3.85% (not statistically significant) in group II; and 0.84%+/-2.34% (not statistically significant) in group III. Left ventricular internal diastolic diameter (mm) was reduced by 4.36+/-4.86 (P=.001) in group I and 1.92+/-5.37 (P=.263) in group II, but increased by 0.22+/-2.54 (not statistically significant) in group III. The results suggest that fish oil leads to accelerated improvement of left ventricular function. The authors believe that if these results are confirmed in larger studies, fish oil should be added to the standard anticongestive therapy of children with DCM.

Crescentic glomerulonephritis in a child with infective endocarditis.

Renal manifestations associated with infective endocarditis (IE) may present with different clinical patterns, and the most common renal histopathological finding is diffuse proliferative and exudative type of glomerulonephritis, leading to hematuria and/or proteinuria. Renal failure due to crescentic glomerulonephritis (CGN) in children with IE is a very rare condition. We report here a 6-year-old boy, who had a history of cardiac surgery for pulmonary atresia and ventricular septal defect, presenting with the clinical findings of IE and hematuria associated with renal failure due to CGN. He was treated with a combination of intravenous (IV) methylprednisolone pulses and appropriate antibiotics, but also received one dose of IV cyclophosphamide. Complete serological, biochemical, and clinical improvement was achieved after 2 months of follow-up. Antibiotic therapy is the essential part of the treatment of IE-associated glomerulonephritis; however, this case also highlights the importance of aggressive immunosuppressive therapy to suppress the immunological process related with infection in this life-threatening condition leading to renal failure.

Childhood mediastinal masses in infants and children.

We reviewed all cases of primary pediatric mediastinal masses diagnosed and treated over a 24-year period. In this study, out of 187 primary mediastinal mass cases diagnosed between 1980 and 2004 in Istanbul University Istanbul Faculty of Medicine, Cardiovascular Surgery Department, 37 pediatric primary mediastinal mass cases were retrospectively evaluated according to age, sex, symptoms, diagnostic procedure, anatomical location, surgical treatment, histopathological evaluation and postoperative adjuvant therapy. The patients ranged in age from 2 months to 15 years at the time of diagnosis, with a mean age of 8 years. There were 24 benign (64.8%) and 13 malignant (35.2%) tumors. The cases were lymphoma (27%), neurogenic tumors (21.6%), cystic lesions (18.9%), germ cell tumors (13.5%), thymic lesions (10.8%) and cardiac tumors (8.1%). Complete and partial resections of the tumor were the surgical procedures performed in 24 patients (64.8%) and 3 patients (8.1%), respectively. The three patients with a malignant tumor, in whom the entire mass could not be removed, received chemotherapy and radiation after surgery. In 10 patients with lymphoma, surgery was not a part of treatment and they received medical and radiation therapy after the establishment of the definitive diagnosis. All patients survived and were discharged from the hospital. Except for the cases with lyphoma, all patients are now free of recurrent disease. Compared to adults, children had more lymphomas and neurogenic tumors. Primary pediatric mediastinal malignancies are relatively common in infants and children. Lymphoma, neurogenic tumors and cystic lesions predominated. These differences between the age groups should also be considered when dealing with a mediastinal mass.

Clinical features of tuberous sclerosis cases.

Tuberous sclerosis (TS) is an autosomal dominant, multisystemic and neurocutaneous disease with high spontaneous mutation rate, and it mostly involves the skin, brain, kidneys, heart and the eyes. This study included 35 patients diagnosed with tuberous sclerosis and aged 6 months to 17 years, with a mean age of 6.5+/-4.8 years. The most frequently observed manifestations were those of the skin (97.1%) and of the central nervous system (seizures 94.2%, mental retardation 51.4%), followed by renal (32.2%), cardiac (25.8%) and ocular (22.5%) manifestations. Among cutaneous manifestations, hypomelanotic macules (94.3%), facial angiofibromas (40%), shagreen spots (20%), fibrous plaques on the forehead (5.7%) and ungula fibromas (5.7%) were observed. Tonic seizures (37.1%) and infantile spasms (21.2%) accounted for majority of seizures. Neurophysiological development was normal in 25.6% of cases, retarded in 51.4% and borderline in 23%. Thirty-four patients had typical pathological findings on magnetic resonance imaging (MRI). In conclusion, the earliest and most frequent complaint is seizure in cases with TS. Careful investigation for hypomelanotic macules and other skin manifestations typical for TS in cases presenting with convulsion makes early diagnosis possible and obviates unnecessary investigations.