Sustitución segura de la lactancia materna para prevenir la transmisión vertical del VIH en la Provincia Central de Kenia / Safe replacement of breast milk to prevent VIH vertical transmission in the Central Province of Kenia

Introducción: la lactancia materna es responsable de hasta un 40% de los contagios perinatales del virus de la inmunodeficiencia humana (VIH) en el África subsahariana. La OMS aconseja evitar por completo la lactancia materna solo si la lactancia artificial es aceptable, factible, asequible, segura y sostenible (AFASS). Material y métodos: se analizaron datos de tres programas del Ministerio de Salud para la prevención de la transmisión vertical (PTV) del VIH, en la Provincia Central de Kenia. Las gestantes VIH+ recibieron información y consejo sobre cómo proteger al bebé durante el embarazo, el parto y el periodo de lactancia. Se administró zidovudina (AZT) desde la vigésimo octava semana, más nevirapina –dosis única– (SD-NVP) intraparto si los linfocitos CD4 eran mayores de 350 cel/mm3, o tratamiento antirretroviral de gran actividad (TARGA) si eran menores de 350 cel/mm3. Los neonatos expuestos recibieron AZT + NVP. Se suministró lactancia artificial (LA), filtros de agua y termos a las madres que optaron por no lactar a sus hijos. Se realizó reacción en cadena de la polimerasa (PCR) para ADN-VIH-1 a las seis semanas de vida. Las madres incluidas en el programa recibían apoyo psicológico individualizado y a través de terapias de grupo. Resultados: la mayoría de las madres (66-96%) se decidieron por la LA; 881 lactantes recibieron leche artificial bien desde el nacimiento o tras un periodo inicial con lactancia materna o con leche de vaca; 515 (58%) fueron dados de alta a los seis meses de edad; 272 (31%) permanecían en el programa (niños < 6 meses) en el momento del análisis de datos. Hubo 59 (6,7%) pérdidas de seguimiento y 12 (1,4%) traslados a otros programas. Un total de 23 (2,6%) lactantes fallecieron. Los neonatos infectados por VIH tuvieron diez veces más probabilidades de morir antes de cumplir seis meses que los no infectados (odds ratio [OR]: 10,55; IC 95% [intervalo de confianza del 95%]: 2,51-41,5), p < 0,001). La morbilidad fue baja; la incidencia de diarrea y de infecciones respiratorias fue de 15,3 y de 42,4 por cada 100 personas/año, respectivamente. Conclusiones: es factible y seguro apoyar la lactancia artificial para madres seropositivas y sus bebés en entornos con escasos recursos en programas integrados en instituciones sanitarias del sector público (AU)

Background: breast feeding accounts for up to 40% of perinatally acquired HIV infection in sub-Saharan Africa. HIV infected mothers are advised by World Health Organization (WHO) to completely avoid breast feeding only if replacement feeding is acceptable, feasible, affordable, safe and sustainable (AFASS). Methods: data were obtained from 3 Ministry of Health PMTCT programs in Central Province, Kenya. HIV positive pregnant women received AZT starting at 28 weeks + intrapartum SD-NVP if CD4>350 or TARGA if CD4<350. HIV exposed infants received AZT + NVP. Infant formula, water filters and thermos flasks were provided to women opting not to breast-feed their infants. ADN-PCR for HIV was obtained at 6 weeks of age. Results: most mothers (66-96%) opted for replacement feeding (RF). Eight hundred and eighty one infants received RF either from birth or after initial breast feeding or cow’s milk. Five hundred and fifteen infants (58%) were discharged after reaching 6 months of age; 272 (31%) were still active (<6 months). There were 59 defaulters (6.7%) and 12 relocations (1.4%). Twenty three infants died (2.6%). HIV-infected infants were more than 10 times more likely to die before 6 months of age than HIV-uninfected infants [OR 10.55 (2.51-41.5) P < 0.001]. Morbidity was low; the incidence of diarrhoea and respiratory tract infection was 15.3 and 42.4 per 100 person-years respectively. Interpretation: it is possible to support safe replacement feeding in resource-limited contexts under routine program conditions within public sector health facilities by employing a feeding methodology that is feasible for mothers and safe for infants (AU)

[Anterograde decremental conduction by left free wall accessory pathway in the permanent form of junctional reciprocating tachycardia]. / Conducción anterógrada decremental por una vía accesoria de pared libre izquierda en la taquicardia incesante tipo Coumel.

We present the case of a 2-month-old infant, diagnosed prenatally with tachycardia. The characteristics of the surface electrocardiogram were consistent with the diagnosis of the permanent form of junctional reciprocating tachycardia: narrow-complex tachycardia at 200 beats/min, negative P' wave in inferior leads (II, III, aVF), I, aVL and from V4 to V6. The tachycardia was incessant despite medical treatment with digoxin, quinidine, amiodarone and flecainide. The electrophysiological study confirmed that the mechanism of the tachycardia was a left posterolateral pathway with long conduction time and decremental properties. The ablation procedure was tried by transseptal approach. During transseptal puncture complete atrioventricular block and interruption of the tachycardia were produced. Decremental ventricular preexcitation was evident during isoproterenol infusion. After recovery of the atrioventricular conduction and incessant tachycardia, radiofrequency ablation of the pathway was performed twelve months later by retrograde approach.

[Radiofrequency ablation of idiopathic left ventricular tachycardia in children]. / Ablación con radiofrecuencia de la taquicardia ventricular izquierda idiopática en niños.

INTRODUCTION: Nowadays radiofrequency catheter ablation is an alternative to medical treatment in adult patients with idiopathic left ventricular tachycardia. AIM: To asses indications, results and long term follow-up of using this technique in children. : Radiofrequency catheter ablation was performed in five consecutive patients without structural heart disease, mean age 8.6+/-7.1 years (range, 1.3 to 17) and suffering from resistance to medical treatment left ventricular tachycardia (2.4+/-0.9 antiarrhythmic drugs per patient). Palpitations and syncope were the clinical manifestations in four patients while congestive heart failure in the other one. Six types of tachycardia were identified in the five-patient group. All of them responded to intravenous verapamil. There were 3 incessant tachycardias and the other three were paroxysmal ones. The ablation site was selected using activation mapping during tachycardia and pace-mapping. The Tachycardia cycle length was 275+/-123 ms and showed right bundle branch block with superior axis (left in 4 and right in 2 cases). The ablation target was located in the mid-septal region of the left ventricle in 3 cases, in the apical and inferior septal region in 2 other cases and in the anterior free wall in the other one. Local activation times preceded in 33+/-13 ms at QRS beginning and with a 12/12 agreement pattern in 5 cases and 9/12 in 1, in whom ablation was unsuccessful. At follow-up, the 4 patients with effective ablation have been tachycardia-free for 35.8+/-17 months. CONCLUSIONS: Radiofrequency catheter ablation is a useful method of treatment in children with idiopathic left ventricular tachycardia, including those under two years old.

[Catheter ablation of accessory pathways in patients with congenital cardiopathies]. / Ablación con catéter de vías accesorias en pacientes con cardiopatías congénitas.

The catheter ablation procedure in patients with accessory pathways and congenital heart defects can potentially become complicated because of abnormal anatomy and atypical conduction system. Eight patients ranging in age from 4.5 months to 18 years with accessory pathways and congenital heart defects underwent radiofrequency ablation. The cardiac diseases were diagnosed as Ebstein anomaly (n = 3), cardiac rhabdomyomas (n = 1), double outlet right ventricle (n = 1), endocardial cushion defect, partial form (n = 1), repaired Fallot's tetralogy (n = 1) and interventricular septal defect (n = 1). Six patients had manifest Wolff-Parkinson-White syndrome and 2 had concealed pathways. One patient with Ebstein anomaly had multiple accessory pathways. Radiofrequency ablation was initially successful in eight of the nine accessory pathways (89%). Two procedures were performed in one patient for pathway recurrence. Procedure was unsuccessful in 1 patient with Ebstein anomaly who later had surgical interruption of the accessory pathway. After a mean follow-up of 30.9 +/- 16.4 months, six of the 7 patients in which pathways were successfully ablated are tachycardia-free. One patient had late recurrence of tachycardia and is well controlled by propafenone.

[Percutaneous valvotomy in critical neonatal pulmonary stenosis. Results and mid-term follow up]. / Valvulotomía percutánea de la estenosis pulmonar crítica neonatal. Resultados y seguimiento a medio plazo.

INTRODUCTION: Catheter-balloon valvotomy has been proposed as an alternative to surgical valvotomy in the critical pulmonary stenosis in newborns. OBJECTIVES: The present report describes the results, complications and follow-up of this technique at our center. METHODS AND RESULTS: From May 1993 to June 1998, fourteen consecutive patients with critical pulmonary stenosis underwent balloon valvotomy. Their mean ages were 8.7 +/- 5.8 days. Each of them was cyanotic and ten of the fourteen were on prostaglandin E1 therapy and three of them required endotracheal intubation and ventilation. The diameters of balloons were 9.6 +/- 2.1 mm (range, 5 to 12 mm) and the balloon/annulus diameter ratio was 1.3 +/- 0.2 (range, 0.8 to 1.5). By means of this technique, right ventricle systolic pressure decreased from 95.2 +/- 22.4 mmHg to 51 +/- 23.2 mmHg (p < 0.001) and the right ventricle/aortic pressure ratio decreased from 1.5 +/- 0.4 to 0.8 +/- 0.3 (p < 0.001). Surgical valvotomy was performed in two patients (cases 1 and 8) at 5-months and 3 days, respectively, from the balloon valvotomy. One patient (case 4) required a blalock-taussig shunt. Complications included cardiac tamponade in one patient. One patient died seven days after successful valvotomy by extracardiac complications. All eleven patients are currently symptom free 26.6 +/- 17.1 months later (range, 5 to 56) and Doppler residual gradient ranges from 0 to 29 mmHg (11.1 +/- 10.4 mmHg). CONCLUSIONS: Balloon pulmonary valvotomy is an effective and relatively safe technique for treatment of critical pulmonary stenosis in newborns with low index complication and mid-term relief of valvular obstruction.