Taquiarritmias supraventriculares no feto. Experiência de uma unidade de referência em cardiologia fetal

OBJETIVO: Avaliar a forma de apresentação, diagnóstico e tratamento das taquiarritmias supraventriculares fetais, através do relato de uma série de casos acompanhados em um centro terciário de cardiologia fetal. MÉTODOS: São descritos 25 casos de taquiarritmia supraventricular diagnosticados intra-útero, no período de janeiro/89 a outubro/97, em uma população compreendendo 3117 gestantes. RESULTADOS: Foram diagnosticados 17 casos de taquiarritmia supraventricular e 8 casos de flutter atrial fetal. As idades gestacionais variaram de 26 a 40 semanas. Doze fetos apresentavam hidropisia no momento do diagnóstico (6 com taquicardia supraventricular (TSV) e 6 com flutter atrial). Quatro fetos com TSV apresentavam cardiopatias estruturais (dois casos de anomalia de Ebstein e dois com comunicação interventricular). Todos os fetos foram internados na Unidade de Cardiologia Fetal para monitorização e tratamento. Entre os 17 fetos com TSV, 12 apresentaram reversão da arritmia após administração de digoxina, mas esta medida não foi eficaz em nenhum paciente com flutter. Dois pacientes com TSV e seis com flutter necessitaram interrupção da gestação para cardioversão elétrica pós-natal. A mortalidade foi de 3/17 no grupo da TSV (incluindo dois pacientes com anomalia de Ebstein) e de 0/8 no grupo com flutter. CONCLUSÃO: As taquiarritmias supraventriculares fetais são eventos raros na população geral. Entretanto, podem provocar insuficiência cardíaca e óbito intra-uterino. Como a resposta ao tratamento é satisfatória, tornam-se de extrema importância o diagnóstico precoce e o tratamento adequado.

Comparison between right and left ventricular myocardia during the human fetal period. Stereological evaluation

PURPOSE: To develop a stereological comparison between right (RV) and left ventricle (LV) myocardium during the third human gestational trimester. METHODS: Five human fetal hearts of the third trimester provided representative samples of 5 RV myocardium and 4 LV myocardium. The material was fixed in 10% buffered formaldehyde, and processed through routine methods. Fifteen microscopic fields were randomly chosen and counted in each ventricular myocardium using an "M-42" test system. The following stereological parameters were assessed: Vv (%), Lv (µm²), Sv (µm²/µm³), Vp (µm³), Nv (1/mm³) and total N. RESULTS: No significant difference between the stereological parameters of the myocardial structures assessed was evidenced, when comparing RV and LV. CONCLUSION: Right and left human ventricular myocardium are very similar during the fetal period at least in regard to their structural aspects.

Detection of functional changes of the fetal heart in the first trimester of gestation

The authors consider the possibility of using color Doppler of the ductus venosus and the measurement of nuchal translucency as a screening test for alterations in fetal cardiac functions in the first trimester of gestation. Review of the literature suggests that the combination of the ultrasonographic measurement of nuchal translucency and Doppler at 10 and 14 weeks of gestation can be effective in detecting certain cardiac abnormalities. This conclusion, however, is preliminary and needs to be further investigated.

Critical aortic stenosis in the neonate. Clinical assessment and surgical outcome in 18 patients

OBJECTIVE - To assess neonates with aortic stenosis with early decompensation operated upon. (LCO) (CHF). METHODS - A and retrospective study analyzing 6 neonates with LCO, group I (GI), and 12 neonates with CHF, group II (GII). Clinical radiographic, electrocardiographic and echocardiographic findings also provided comparative bases for the study, as did surgical and evolutional findings. RESULTS - The mean ages at hospitalization and surgery (p = 0.0031) were 14.3 and 14.8 days in GI and 35.4 and 42.8 days in GII, respectively. Cardiac murmurs were more intense in GII (p = 0.0220). The aortic ring was smaller in GI (8.0 ± 2.5mm) as compared to GII (11.4±1.4mm) (p = 0.2882). Ventricular function was reduced to 18±5.5% and 33.3±7.6% in GI and GII, respectively (p = 0.0162). Aortic atresia, however, was present only in 2 neonates in GI. Five of 6 patients in GI died but all patients in GII survived (p=0.0007). In the latter group, 84.6% of the patients were in functional class I (FC-I) in the long-term follow-up, with moderate residual lesions in 6 neonates, discrete residual lesions in 4, and reoperation in 2. CONCLUSION - Aortic stenosis is a severe anomaly of the neonate, whose immediate evolution depends on the pre-operative anatomic and functional findings, and the late evolution essentially depends on the anatomic features of the valve.

The Brugada syndrome. Outcome of one case

The Brugada syndrome is a rare condition, and due to its mutating manner of presentation it may be difficult to diagnose. We report one case and discuss the diagnostic aspects and the clinical outcome of one patient with characteristic findings of this syndrome. These findings are especially defined by J-ST elevation in the right leads of serial electrocardiographic records, wide oscillations of J points and ST segments during 24-hour Holter monitoring, and nocturnal sudden death. We stress the importance of the Holter monitor findings for diagnostic complementation. Through this method it is possible to establish a correlation between vigil activities and sleep and the variability of the degree of impairment in ventricular repolarization.

Clinical outcome of patients with familial hypercholesterolemia and coronary artery disease undergoing partial ileal bypass surgery

Familial hypercholesterolemia is characterized by high serum levels of total cholesterol and LDL-cholesterol. It may be homozygous or heterozygous. In homozygous patients, LDL-cholesterol levels range from 500 to 1000mg/dL and coronary artery disease is precocious, usually manifesting itself between the 2nd and 3rd decades of life. The diagnosis is often made by the presence of xanthoma tuberosum and tendinous xanthomas that appear between the 1st and 2nd decades of life. The use of high doses of statins or even unusual procedures (apheresis, partial ileal bypass surgery, liver transplantation, gene therapy), or both, is necessary for increasing survival and improving quality of life, because a reduction in cholesterol levels is essential for stabilizing the coronary artery disease and reducing xanthomas. We report our experience with 3 patients with xanthomatous familial hypercholesterolemia and coronary artery disease, who underwent partial ileal bypass surgery. Their follow-up over the years (approximately 8 years) showed a mean 30% reduction in total cholesterol, with a significant reduction in the xanthomas and stabilization of the coronary artery disease.

Fetal tachyarrhythmia with 1:1 atrioventricular conduction. Adenosine infusion in the umbilical vein as a diagnostic test

This is the report of a case of fetal tachyarrhythmia with 1:1 atrioventricular conduction detected by pre-natal echocardiography in a fetus at 25-weeks gestation. Adenosine infusion via cordocentesis was performed as a diagnostic test to differentiate between atrioventricular nodal reentrant supraventricular tachyarrhythmia and atrial flutter. After infusion, transient 2:1 atrioventricular dissociation was obtained and the diagnosis of atrial flutter was made. Transplacental therapy with digoxin and amiodarone was then successfully used.

Outcome of acute renal failure associated with cardiac surgery in infants

OBJECTIVE: To analyze the impact of acute renal failure (ARF) on the evolution of infants undergoing cardiac surgery. METHODS: We assessed 15 infants undergoing cardiac surgery who developed (ARF). Their demographic, clinical and surgical data, and evolution were analyzed. RESULTS: Their mean age was 4.4±4.0 months (8 days to 24 months). Twelve infants were males, and 4 patients already had ARF at surgery. The primary cause of ARF was immediate acute cardiac dysfunction in 10 infants, cardiac dysfunction associated with sepsis in 2 infants, and isolated sepsis in 3 infants. All children depended on mechanical ventilation during their postoperative period, 14 infants used vasoactive drugs, and 11 had an infectious process associated with ARF. Thirteen infants required dialytic treatment. Eleven infants developed oluguric ARF, and all had to undergo peritoneal dialysis; of the 4 patients with non-oliguric, 2 required dialysis, the main indication being hypervolemia. Of these 13 dialyzed infants, 4 died in the first 24 hours because of the severity of the underlying cardiac disease (mean urea level of 49±20 mg/dl). The mortality rate for the entire group was 60% , and it was higher among the patients with oliguria ARF (73% vs 25%, p<0.001). The cause of death was acute cardiac dysfunction in 6 infants (early type-1ARF) and sepsis in the 3 remaining infants (late type-2 ARF). CONCLUSION: The mortality rate of ARF associated with cardiac surgery in infants was hight, being higher among children with oliguria; peritoneal dialysis was indicated due to clinically uncontrolled hypervolemia and not to the uremic hypercatabolic state.

Influence of the echocardiographic score and not of the previous surgical mitral commissurotomy on the outcome of percutaneous mitral balloon valvuloplasty

OBJECTIVE: To evaluate prior mitral surgical commissurotomy and echocardiographic score influence on the outcomes and complications of percutaneous mitral balloon valvuloplasty. METHODS: We performed 459 complete mitral valvuloplasty procedures. Four hundred thirteen were primary valvuloplasty and 46 were in patients who had undergone prior surgical commissurotomy. The prior commissurotomy group was older, had higher echo scores, and a tendency toward a higher percentage of atrial fibrillation. RESULTS: When the groups were compared with each other, no differences were found in pre- and postprocedure mean pulmonary artery pressure, mean mitral gradient, mitral valve area, and mitral regurgitation . Because we found no significant differences, we subdivided the entire group based on echo scores, those with echo scores <=8 and those with echo scores >8 the mitral valve area being higher in the <=8 echo score group 2.06±0.42 versus 1.90±0.40cm² (p=0.0090) in the >8 echo score group. CONCLUSION: Dividing the groups based on echo score revealed that the higher echo score group had smaller mitral valve areas postvalvuloplasty.

A relação entre família e escola e a perspectiva de minimização das dificuldades comportamentais e cognitivas apresentadas por adolescentes com Síndrome do Alcoolismo Fetal (SAF): estudos de casos na cidade de Manaus

Dissertação de mestrado em Educação Especial (área de especialização em Dificuldades de Aprendizagem Específicas)

Sex differences in the fetal heart rate variability indices of twins

Aims: To evaluate the differences in linear and complex heart rate dynamics in twin pairs according to fetal sex combination [male-female (MF), male-male (MM), and female-female (FF)]. Methods: Fourteen twin pairs (6 MF, 3 MM, and 5 FF) were monitored between 31 and 36.4 weeks of gestation. Twenty-six fetal heart rate (FHR) recordings of both twins were simultaneously acquired and analyzed with a system for computerized analysis of cardiotocograms. Linear and nonlinear FHR indices were calculated. Results: Overall, MM twins presented higher intrapair average in linear indices than the other pairs, whereas FF twins showed higher sympathetic-vagal balance. MF twins exhibited higher intrapair average in entropy indices and MM twins presented lower entropy values than FF twins considering the (automatically selected) threshold rLu. MM twin pairs showed higher intrapair differences in linear heart rate indices than MF and FF twins, whereas FF twins exhibited lower intrapair differences in entropy indices. Conclusions: The results of this exploratory study suggest that twins have sex-specific differences in linear and nonlinear indices of FHR. MM twins expressed signs of a more active autonomic nervous system and MF twins showed the most active complexity control system. These results suggest that fetal sex combination should be taken into consideration when performing detailed evaluation of the FHR in twins.

Fetal behavior and heart rate in twin pregnancy: a review

Fetal movements and fetal heart rate (FHR) are well-established markers of fetal well-being and maturation of the fetal central nervous system. The purpose of this paper is to review and discuss the available knowledge on fetal movements and heart rate patterns in twin pregnancies. There is some evidence for an association or similarity in fetal movement incidences or FHR patterns between both members of twin pairs. However, the temporal occurrence of these patterns seems to be for the most part asynchronous, especially when stricter criteria are used to define synchrony. The available data suggest that fetal behavior is largely independent of sex combination, fetal position, and presentation. Conversely, chorionicity appears to have some influence on fetal behavior, mainly before 30 weeks of gestation. There is preliminary evidence for the continuity of inter-individual differences in fetal activity and FHR patterns over pregnancy. Comparisons between studies are limited by large methodological differences and absence of uniform concepts and definitions. Future studies with high methodological quality are needed to provide a more comprehensive knowledge of normal fetal behavior in twin pregnancy.