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.

Real-Time PCR analysis of af4 and dek genes expression in acute promyelocytic leukemiat (15;17)patients

Among several newly identified oncogenes, dek and af4 are attractive targets for researchers interested with leukemia. In this study quantitative Real-Time RT-PCR technique was used to define alterations in expression of dek and af4 genes associated with acute promyelocytic leukaemia (APL) t (15; 17). RNA samples obtained from bone marrow aspirates of fourteen APL patients, cDNA portions were labelled with Syber Green 1 dye and LightCycler analysis have been performed. Expression changes in patients were found not significant in comparison to healthy donors for af4 (P=0.192) and dek (P= 0.0895). We suggest that af4 gene may have a role in leukomogenesis restricted to lymphoblastic lineage; also further studies must carry on with a larger series of patients in order to understand the relationship between the dek gene and APL. Our study was the first attempt for analysing dek and af4 genes in APL t (15; 17) patients by quantitative Real-Time RT-PCR. This rapid and sensitive method could be used to screen these genes in different types of leukaemia.