Tetralogy of Fallot Repair After Neonatal Right Ventricular Outflow Tract Stenting: Initial Multicenter Experience in Argentina.

Initial management of patients with tetralogy of Fallot, unfavorable anatomy, and reduced pulmonary blood flow is controversial and continues to be a clinical challenge. Pulmonary to systemic shunt anastomosis or primary correction in neonates and small infants is associated with higher morbimortality and increased number of reoperations. Initial right ventricle outflow tract stenting palliation has emerged as an attractive alternative. We report our experience in 14 patients operated on with tetralogy of Fallot and previous right ventricle outflow tract stenting from March 2018 to June 2022. All stented patients had pulmonary annulus and main pulmonary artery Z score ≤ -2.5. Surgical outcomes, complications, and mortality at 30 days were evaluated. Patient's age and weight at surgery were 5.9 months (2-17) and 6.1 kg (3.9-8.9), respectively. Stents were completely removed in 57.1% of patients. A transannular patch was placed in 10 patients, 3 patients required a right ventricle to pulmonary artery conduit due to coronary anomalies and in 1 patient, the pulmonary valve was preserved. Length of stay and ventilation time were 13.6 days (5-27) and 44.8 h (6-44), respectively. Mean time for right ventricle outflow tract stent implantation to surgical correction was 4 months (2-16). There was no mortality, and mean follow-up time of this cohort was 23.1 month (1-41). Surgical correction of severe tetralogy of Fallot after right ventricle outflow tract stenting is an effective alternative achievable without an increase in morbidity and mortality. Difficulty in stent extraction is related to the time since implantation. More number of patients and longer follow-up time are needed to confirm these initial results.

Magnetic resonance lymphangiography in group 1 paediatric pulmonary arterial hypertension.

Pulmonary hypertension could have thoracic lymphatic abnormalities caused by right ventricular failure. Since there is no description of such abnormalities, the purpose of this study was to investigate them with magnetic resonance. Prospective review magnetic resonance T2-weighted lymphangiography was performed between January 2017 and October 2019 through quantitative thoracic duct diameter, diameter index and qualitative lymphatic abnormalities types: 1 - little or none abnormalities, 2 - abnormalities in supraclavicular region, 3 - abnormalities extending into the mediastinum and 4 - abnormalities extending into the lung. Five patients with group 1 pulmonary arterial hypertension participated in this study. The mean age was 12.44 ± 4.92 years, three male and two female. The quantitative analysis yielded the following results: mean thoracic duct diameter of 2.92 ± 0.16 mm and thoracic duct index 2.28 ± 1.03 mm/m2. Qualitative lymphangiography abnormalities were type 1 in three patients, type 2 in one, all with low-risk determinants, and type 3 in one with high-risk determinants and right ventricular failure. Magnetic resonance T2-weighted lymphangiography in group 1 paediatric pulmonary arterial hypertension allowed for the identification of the thoracic duct, which was used to perform both quantitative and qualitative analysis of thoracic lymphatic abnormalities, in particular when increased high-risk determinants and right ventricular failure were present. These features represent an extracardiac finding useful to understand systemic venous congestion impact on lymphatic system.

Efficacy of citrulline supplementation to decrease the risk of pulmonary hypertension after congenital heart disease surgery. A local experience.

Introduction: Pulmonary hypertension (PH) is a major cause of morbi-mortality among patients with congenital heart disease (CHD) and also a potentially severe complication after surgical repair. Oral citrulline, a precursor to NO synthesis, is safe and efficacious for decreasing the risk of postoperative PH. Objective: Objetive: The aim of the present study was to investigate in pediatric patients the changes of plasma citrulline, arginine, homocysteine and nitric oxide (NO) metabolites and pulmonary artery pressures (PAP) pre-post cardiac surgery in order to describe our population status with regard to the risk of pulmonary hypertension and look for potential biomarkers for early detection and treatment. Main results/Discussion: 16 Argentine pediatric patients with CHD undergoing cardiopulmonary bypass were randomized in two groups: (A) with and (B) without perioperative citrulline supplementation. We found that plasma citrulline median levels before surgery were lower in both groups respect to referential values, probably due to the poor nutritional status of our patients; only group A surpassed post-surgery the minimum recommended level to avoid PH. Furthermore, none of the patients in group A showed mean PAP higher than 20 mmHg, whereas in group B, 67% of the measurements were ≥ than the reference level. Conclusions: We reaffirm that citrulline supplementation it is effective in reducing postoperative pulmonary hypertension and biomarkers could evidence patient status as a translational medicine application.

Implante de stent en tracto de salida de ventrículo derecho en tetrología de Fallot grave: alternativa a la anastomosis de Blalock-Taussig / Right Ventricular Outflow Tract Stenting in Severe Tetralogy of Fallot: an Option to the Blalock-Taussig Shunt

RESUMEN Introducción: El manejo inicial de pacientes con tetralogía de Fallot (TOF) asociado a una anatomía desfavorable y flujo vascular pulmonar significativamente reducido es controversial y continúa siendo un desafío clínico. Material y métodos: Estudio multicéntrico, retrospectivo, observacional. Se incluyeron pacientes consecutivos (neonatos y lactantes menores) con diagnóstico de TOF asistidos en cuatro centros diferentes de la ciudad de Córdoba, Argentina, que recibieron stent en tracto de salida de ventrículo derecho (TSVD) como abordaje inicial de su cardiopatía congénita. La indicación de intervención paliativa inicial fue consensuada en reunión del equipo cardiovascular en cada centro participante. Una anatomía compleja (ramas pulmonares con Z score ≤ -2,5), presentación en shock cardiogénico o en crisis de cianosis, bajo peso o comorbilidades significativas (enterocolitis necrotizante, prematurez, insuficiencia renal, convulsiones) inclinaron la decisión hacia un abordaje percutáneo inicial. Resultados: Entre agosto de 2017 hasta mayo de 2018, 6 pacientes con TOF sintomáticos recibieron stent en TSVD. La edad media fue 39,3 días (9-87), el peso medio fue 3,60 kg (2,2-5,4) y el 66% eran de sexo femenino. Los stents utilizados fueron coronarios o periféricos con un diámetro que varió entre 4,0 y 6,0 mm. La saturación periférica previa a la colocación del stent fue de 66,4% (42-77) incrementado a 90,6% (86-96) previo al alta (p < 0,001). No se registraron complicaciones durante la intervención. El tiempo de internación fue de 7 días (1-13) y el tiempo de seguimiento fue de 106,8 días (4-292). No hubo mortalidad a los 30 días. Conclusión: El implante de stent en TSVD en pacientes con TOF y anatomía desfavorable es una opción razonable en neonatos y lactantes menores como alternativa a la realización de una anastomosis de Blalock-Taussig modificada o corrección primaria inicial.

ABSTRACT Background: The initial management of patients with Tetralogy of Fallot (TOF) associated with unfavorable anatomy and significantly reduced pulmonary blood flow is controversial and still a clinical challenge. Methods: We conducted a multicenter, retrospective and observational study in consecutive neonates and young infants with diagnosis of TOF treated at four different centers of the city of Cordoba, Argentina, who underwent RVOT stenting as the first approach to alleviate their congenital heart defect. The indication of a primary palliative intervention was decided by the cardiovascular surgery team in each participating center. An initial percutaneous approach was considered under the following circumstances: complex anatomy (pulmonary branches with Z score ≤-2.5), cardiogenic shock, cyanotic spells, low weight or significant comorbidities (necrotizing enterocolitis, prematurity, kidney dysfunction or convulsions). Results: From August 2017 to May 2018, 6 patients with symptomatic TOF underwent RVOT stenting. Mean age was 39.3 days (9-87), mean weight was 3.60 kg (2.2-5.4) and 66% were girls. Coronary or peripheral stents were used with diameter between 4.0 mm and 6.0 mm. Systemic arterial oxygen saturation was 66.4% (42-77) before the procedure and increased to 90.6% (86-96) before discharge (p<0.001) There were no complications during the procedure. Patients were hospitalized for an average of 7 days (1-13) and mean follow-up was 106.8 days (4-292). There were no deaths at 30 days. Conclusions: Right ventricular outflow tract stenting in patients with TOF and unfavorable anatomy is a reasonable option for neonates and young infants as an alternative to the modified Blalock-Taussig shunt or initial primary corrective surgery.

Cuantificación de resultados en cirugía de cardiopatía congénita 2012-2015: cuatro años de experiencia con el programa colaborativo internacional de mejoría de calidad / Quantification of Outcomes in Surgery for Congenital Heart Diseases in 2012-2015: a Four-Year Experience with the International Quality Improvement Collaborative Program

RESUMEN Introducción: El sistema de salud experimenta un creciente interés en cruzar el abismo de calidad. La cirugía de cardiopatías congénitas ha mejorado en resultados y calidad de vida; no obstante tiene riesgo de mortalidad e infección que requieren cuantificación. El objetivo de este trabajo fue cuantificar sus resultados a través del Programa Colaborativo Internacional para Mejoría de Calidad en cirugía de cardiopatías congénitas para mejorar. Material y métodos: Estudio prospectivo intervencionista, en Hospital Público Terciario de Niños, Córdoba, Argentina. Se incluyeron pacientes con cirugía de cardiopatías congénitas desde el 1 de enero de 2012 al 31 de diciembre de 2015; se cuan-tificó sexo, edad y peso en cirugía de cardiopatías congénitas, riesgo ajustado a complejidad, porcentaje no ajustado e índices estándar de mortalidad intrahospitalaria e infección estándar (índice observado/índice esperado) con intervalos de confianza del 95% y se comparó con el estándar del Programa Colaborativo para Mejoría de Calidad (1,0 = estándar, < 1= mejoría). Como intervención se introdujeron las guías conductoras: prácticas perioperatorias seguras, control de infección y trabajo en equipo. Resultados: Se efectuaron 373 cirugías de cardiopatías congénitas en 203 varones, 170 mujeres con porcentaje con porcentaje de distribución RACHS-1 : I:28,4%, II:44%, III:24,4% y IV-VI 3,2%. El porcentaje semestral de mortalidad no ajustado fue del 6%, 3%, 8%, 9%, 11%, 0%, 0% y 5%, respectivamente (estándar 4-6%). El índice estándar de mortalidad intrahospitalaria y el intervalo de confianza fueron 0,85 (0,23-2,18), 1,82 (0,79-3,59), 1,07 (0,39-2,34), 0,36 (0,04-1,29), respectivamente. El porcentaje semestral de infección no ajustado fue 24%, 23%, 25%, 14%, 13%, 6%, 9% y 16%, respectivamente (estándar 5-7%). El índice de infección estándar y el intervalo de confianza fueron 1,89 (1,12-2,99), 1,87 (1,17-2,83), 2,0 (1,20-3,12), 1,22 (0,61-2,18). Conclusiones: La implementación del Programa Colaborativo para Mejoría de Calidad en cirugía de cardiopatías congénitas del Hospital Público Terciario de Niños, Córdoba, Argentina contribuyó a cuantificar resultados e introducir la implementación de guías conductoras para mejorarlos. Se logró la reducción en mortalidad, en tanto la infección continúa por mejorar.

ABSTRACT Background: The health care system is undergoing an increasing interest in crossing the quality chasm. Surgery for congenital heart defects has improved in terms of outcomes and quality of life; however, the risk of mortality and infection requires to be quantified. The goal of this study was to quantify the outcomes of surgery for congenital heart diseases following the International Quality Improvement Collaborative (IQIC) for Congenital Heart Disease program. Methods: This observational and interventional study was conducted at a tertiary children's hospital in Cordoba, Argentina. Patients undergoing surgery for congenital heart defects between January 1, 2012, and December 31, 2015, were included. The following variables were quantified: sex, age, weight, risk-adjusted congenital heart surgery score, non-adjusted risk, standardized in-hospital mortality ratios and standardized infection ratio (observed rate/expected rate) with their correspond-ing 95% confidence intervals. The results were compared with the IQIC for Congenital Heart Disease program standards (1.0=standardized rates, <1=improvement). The IQIC guidelines based on key drivers -safe perioperative practice, reduction of infections and team-based practice- were implemented as intervention for improvement. Results: A total of 373 surgical procedures for congenital heart defects were performed on 203 male patients and 170 female patients assigned to the following RACHS-1 categories: I: 28.4%, II: 44%, III: 24.4% and IV-VI 3.2%. Non-adjusted mortality rate at 6 months was of 6%, 3%, 8%, 9%, 11%, 0%, 0% and 5%, respectively (standardized rates 4-6%). Standardized in-hospital mortality ratios and their corresponding confidence intervals were 0.85 (0.23-2.18), 1.82 (0.79-3.59), 1.07 (0.39-2.34), and 0.36 (0.04-1.29), respectively. Non-adjusted infection rate at 6 months was of 4%, 23%, 25%, 14%, 13%, 6%, 9% and 16%, respectively (standardized rates 5-7%). Conclusion: The implementation of the International Quality Improvement Collaborative for Congenital Heart Disease program with the use of guidelines based on key drivers in a public tertiary hospital in Cordoba, Argentina, contributed to quantifying and improving the outcomes. While mortality decreased, the rate of infections is still to be improved.

Impresión tridimensional en doble vía de salida del ventrículo derecho para simplificar la reparación intraventricular / Three-Dimensional Printing Model in Double-Outlet Right Ventricle to Simplify Intraventricular Repair

RESUMEN: Introducción: El síndrome de burnout genera impacto negativo en la actuación profesional, la seguridad del paciente y la vida del residente. Esta problemática ha tomado vigencia en las residencias argentinas; sin embargo, no se han evaluado medidas efectivas para prevenir su aparición. Objetivo: Evaluar la prevalencia del síndrome de burnout antes y después de la implementación del descanso postguardia en médicos residentes de cardiología. Material y métodos: Estudio analítico, prospectivo. Se implementó el cuestionario de Maslach en residentes de cardiología de una institución de la Ciudad de Buenos Aires, antes y después de la implementación de un período de descanso de 24 horas (DPG) luego de una guardia de 24h. Resultados: La encuesta fue respondida por 42 residentes (2014: 19; 2015: 23). Hubo una tendencia a menor prevalencia de burnout en el grupo con DPG (26,1% vs. 47,4% p = 0,152) y mejores resultados en la escala de despersonalización (19 11-21 vs. 10 [1-17] p = 0,023). Presentaron menor agotamiento y despersonalización las mujeres y los mudados a Buenos Aires. Conclusiones: La implementación del DPG se asoció a la reducción de la escala de despersonalización, principalmente en mujeres. Se remarca la importancia de crear estrategias de prevención que mejoren las condiciones de trabajo y la calidad de vida del residente.

Clinical findings in 32 patients with 22qll.2 microdeletion attended in the city of Córdoba, Argentina.

The 22q11.2 microdeletion is the most common deletion syndrome, with a prevalence of 1/4000-1/6000 among newborn infants and a wide phenotypic variability. The diagnosis of the 22q11.2 microdeletion is made through cytogenetics or fuorescence in situ hybridization (FISH). The objectives of this article were to describe the clinical features of 32 patients with 22q11.2 microdeletion and the fndings of other chromosomal abnormalities and genetic syndromes in phenotypically similar patients. This series was made up of 268 patients with clinical criteria supporting the diagnostic suspicion attended at the Hospital de Niños and Hospital Privado, of Córdoba, between March 1st, 2004 and August 31st, 2011. The following parameters were analyzed: age at the time of the diagnosis, sex, clinical manifestations, and mortality. Thirty-two patients (19 males and 13 females) had a positive result for this deletion. The diagnosis was made mostly in their frst months and years of life (age range: 7 days old-31 years old). The clinical manifestations were: congenital heart diseases (22/32), thymic hypoplasia-agenesis/ recurrent infections (10/32), velopalatal insuffciency (8/32). Five patients died; four due to a complication associated with their cardiovascular disease and one due to multiple organ failure. The clinical manifestations of the syndrome were varied.

Clinical fndings in 32 patients with 22qll.2 microdeletion attended in the city of Córdoba, Argentina / Hallazgos clínicos en 32 pacientes con microdeleción 22q11.2 asistidos en la ciudad de Córdoba, Argentina

The 22q11.2 microdeletion is the most common deletion syndrome, with a prevalence of 1/4000-1/6000 among newborn infants and a wide phenotypic variability. The diagnosis of the 22q11.2 microdeletion is made through cytogenetics or fuorescence in situ hybridization (FISH). The objectives of this article were to describe the clinical features of 32 patients with 22q11.2 microdeletion and the fndings of other chromosomal abnormalities and genetic syndromes in phenotypically similar patients. This series was made up of 268 patients with clinical criteria supporting the diagnostic suspicion attended at the Hospital de Niños and Hospital Privado, of Córdoba, between March 1st, 2004 and August 31st, 2011. The following parameters were analyzed: age at the time of the diagnosis, sex, clinical manifestations, and mortality. Thirty-two patients (19 males and 13 females) had a positive result for this deletion. The diagnosis was made mostly in their frst months and years of life (age range: 7 days old-31 years old). The clinical manifestations were: congenital heart diseases (22/32), thymic hypoplasia-agenesis/ recurrent infections (10/32), velopalatal insuffciency (8/32). Five patients died; four due to a complication associated with their cardiovascular disease and one due to multiple organ failure. The clinical manifestations of the syndrome were varied.

La microdeleción 22q11.2 es la más frecuente, afecta a 1/4000 a 1/6000 recién nacidos y tiene amplia variabilidad fenotípica. El diagnóstico se realiza por citogenética o hibridación in situ fuorescente (FISH). Los objetivos del presente trabajo fueron describir las características clínicas de 32 pacientes con microdeleción 22q11.2, y los hallazgos de otras anomalías cromosómicas y síndromes genéticos en pacientes fenotípicamente similares. La serie estuvo compuesta por 268 pacientes que tenían criterios clínicos de sospecha diagnóstica asistidos en los hospitales de Niños y Privado de Córdoba, desde el 1 de marzo de 2004 hasta el 31 de agosto de 2011. Se analizaron: edad en el momento del diagnóstico, sexo, manifestaciones clínicas y mortalidad. Resultaron positivos para esta deleción, 32 pacientes (19 varones y 13 mujeres). El diagnóstico se realizó mayoritariamente en los primeros meses y años de vida (rango etario: 7 días a 31 años). Clínica: cardiopatías congénitas (22/32), hipoplasia-agenesia-tímica/ infecciones recurrentes (10/32); hipotonía velopalatina (8/32). Cinco murieron, cuatro por complicación de su patología cardiovascular y uno por falla multisistémica. La expresividad clínica de la enfermedad fue variable.

Clinical fndings in 32 patients with 22qll.2 microdeletion attended in the city of Córdoba, Argentina / Hallazgos clínicos en 32 pacientes con microdeleción 22q11.2 asistidos en la ciudad de Córdoba, Argentina

The 22q11.2 microdeletion is the most common deletion syndrome, with a prevalence of 1/4000-1/6000 among newborn infants and a wide phenotypic variability. The diagnosis of the 22q11.2 microdeletion is made through cytogenetics or fuorescence in situ hybridization (FISH). The objectives of this article were to describe the clinical features of 32 patients with 22q11.2 microdeletion and the fndings of other chromosomal abnormalities and genetic syndromes in phenotypically similar patients. This series was made up of 268 patients with clinical criteria supporting the diagnostic suspicion attended at the Hospital de Niños and Hospital Privado, of Córdoba, between March 1st, 2004 and August 31st, 2011. The following parameters were analyzed: age at the time of the diagnosis, sex, clinical manifestations, and mortality. Thirty-two patients (19 males and 13 females) had a positive result for this deletion. The diagnosis was made mostly in their frst months and years of life (age range: 7 days old-31 years old). The clinical manifestations were: congenital heart diseases (22/32), thymic hypoplasia-agenesis/ recurrent infections (10/32), velopalatal insuffciency (8/32). Five patients died; four due to a complication associated with their cardiovascular disease and one due to multiple organ failure. The clinical manifestations of the syndrome were varied.(AU)

La microdeleción 22q11.2 es la más frecuente, afecta a 1/4000 a 1/6000 recién nacidos y tiene amplia variabilidad fenotípica. El diagnóstico se realiza por citogenética o hibridación in situ fuorescente (FISH). Los objetivos del presente trabajo fueron describir las características clínicas de 32 pacientes con microdeleción 22q11.2, y los hallazgos de otras anomalías cromosómicas y síndromes genéticos en pacientes fenotípicamente similares. La serie estuvo compuesta por 268 pacientes que tenían criterios clínicos de sospecha diagnóstica asistidos en los hospitales de Niños y Privado de Córdoba, desde el 1 de marzo de 2004 hasta el 31 de agosto de 2011. Se analizaron: edad en el momento del diagnóstico, sexo, manifestaciones clínicas y mortalidad. Resultaron positivos para esta deleción, 32 pacientes (19 varones y 13 mujeres). El diagnóstico se realizó mayoritariamente en los primeros meses y años de vida (rango etario: 7 días a 31 años). Clínica: cardiopatías congénitas (22/32), hipoplasia-agenesia-tímica/ infecciones recurrentes (10/32); hipotonía velopalatina (8/32). Cinco murieron, cuatro por complicación de su patología cardiovascular y uno por falla multisistémica. La expresividad clínica de la enfermedad fue variable.(AU)

Clinical findings in 32 patients with 22qll.2 microdeletion attended in the city of Córdoba, Argentina. / Clinical findings in 32 patients with 22qll.2 microdeletion attended in the city of Córdoba, Argentina.

The 22q11.2 microdeletion is the most common deletion syndrome, with a prevalence of 1/4000-1/6000 among newborn infants and a wide phenotypic variability. The diagnosis of the 22q11.2 microdeletion is made through cytogenetics or fuorescence in situ hybridization (FISH). The objectives of this article were to describe the clinical features of 32 patients with 22q11.2 microdeletion and the fndings of other chromosomal abnormalities and genetic syndromes in phenotypically similar patients. This series was made up of 268 patients with clinical criteria supporting the diagnostic suspicion attended at the Hospital de Niños and Hospital Privado, of Córdoba, between March 1st, 2004 and August 31st, 2011. The following parameters were analyzed: age at the time of the diagnosis, sex, clinical manifestations, and mortality. Thirty-two patients (19 males and 13 females) had a positive result for this deletion. The diagnosis was made mostly in their frst months and years of life (age range: 7 days old-31 years old). The clinical manifestations were: congenital heart diseases (22/32), thymic hypoplasia-agenesis/ recurrent infections (10/32), velopalatal insuffciency (8/32). Five patients died; four due to a complication associated with their cardiovascular disease and one due to multiple organ failure. The clinical manifestations of the syndrome were varied.

Percutaneous closure of the patent ductus arteriosus using the Nit-Occlud PDA-R (reverse) device: initial experience reporting immediate and short-term results.

PURPOSE: To review the initial clinical outcomes of patent ductus arteriosus (PDA) closure using the new Nit-Occlud PDA-R device (NOPDA-R). MATERIALS AND METHODS: The NOPDA-R is a self-expandable, nitinol-made, premounted and cone-shaped device with two distinctive features: reverse reconfiguration of the distal disc and a peculiar "snare-like" release mechanism. From May to December 2010, 20 consecutive patients were included. RESULTS: Median age was 4.7 years (range, 6 months to 21 years) and weight was 16.4 kg (range, 6-49 kg). Mean PDA diameter at its narrowest point, usually the pulmonary end, was 2.92 ± 0.61 mm (range, 2.1-4.5 mm), length was 7.05 ± 1.17 mm (range, 4.7-9.2 mm) and diameter of the aortic ampulla was 9.52 ± 1.62 mm (range, 6-13 mm). Pulmonary artery mean pressure was 20.6 ± 4.49 mmHg (range, 14-28 mmHg) and Qp/Qs ratio was 2.0 ± 0.29 (range, 1.6- 2.5). Implantation success rate was 100%. The median cylinder diameter of the device was 6.53 ± 1.05 mm (range, 5.5-8.5 mm) leading to a final selected device 124% larger (cylinder diameter) than the narrowest PDA diameter. Assessed by transthoracic color-Doppler echocardiography at 24 hours, 1 month, and 3 months after implantation, complete closure was achieved in 60%, 90%, and 95% of patients, respectively. There were no complications and all patients were discharged home the next day. CONCLUSION: Percutaneous PDA closure using the new NOPDA-R device was feasible, safe, and effective. Longer follow-up time and a larger number of patients are required to assess long-term performance.

Utilización del "balón con cuchillas" para ampliación de comunicación interauricular restrictiva en lactantes menores de 6 meses: resultados inmediatos y a mediano plazo / Blade Balloon Septostomy to Enlarge a Restrictive Atrial Septal Defect in Infants under 6 Months: Immediate and Medium-Term Outcomes

Los pacientes con cardiopatías congénitas complejas requieren con cierta frecuencia una comunicación interauricular no restrictiva para mantener una saturación de oxígeno arterial y un gasto cardíaco adecuados. En este trabajo se describen seis pacientes menores de 6 meses con cardiopatías congénitas cianóticas graves, en los cuales se realizó dilatación de una comunicación interauricular restrictiva utilizando un balón con cuchillas. Se presentan los resultados inmediatos y a mediano plazo. En todos los pacientes se logró un incremento importante y duradero del tamaño del defecto interauricular y una mejoría clínica sostenida posprocedimiento. Se resalta la utilización de la ecocardiografía intraprocedimiento para guiar y evaluar los resultados. Consideramos que, utilizada con cautela en casos seleccionados, la ampliación de una CIA restrictiva con balón con cuchillas en lactantes menores de 6 meses es una alternativa segura y eficaz, con resultados satisfactorios. La monitorización ecocardiográfica es muy importante para el éxito del procedimiento.

A nonrestrictive atrial septal defect is mandatory in order to maintain adequate arterial oxygen saturation and cardiac output in patients with complex congenital heart defects. We describe six patients under 6 months with severe cyanotic congenital heart defects in whom blade balloon septostomy was performed to enlarge a restrictive atrial septal defect. Immediate and medium-term outcomes are presented. The procedure was successful in all patients, producing a larger and long-lasting atrial septal defect and sustained clinical improvement. The use of intraprocedure echocardiography to guide and evaluate the results is highlighted. We consider that balloon septostomy is a safe and effective option to enlarge a restrictive ASD in carefully selected cases in infants less than 6 months old, with satisfactory outcomes. Echocardiography guidance is very important to warrant success of the procedure.

Systemic hypertension and transient ischemic attack in a 6-year-old girl with fibromuscular dysplasia treated with percutaneous angioplasty.

We describe a 6-year-old girl with arterial hypertension secondary to fibromuscular dysplasia with stenoses of both renal arteries and transient ischemic attack due to extracranial right internal carotid artery subtotal occlusion as well as left internal carotid artery stenosis. She was treated with percutaneous angioplasty of both renal and both carotid arteries.

Some components of the cardiac ß-adrenergic system are altered in the chronic indeterminate form of experimental Trypanosoma cruzi infection.

The chronic indeterminate form of Trypanosoma cruzi infection could be the key to knowing which patients will develop chagasic myocardiopathy. Infected mice present a period in which cardiac functional and structural alterations are different from those described for acute or chronic phases. We studied some components of the cardiac ß-adrenergic system in mouse hearts infected with T. cruzi Tulahuen strain or SGO-Z12 isolate during the chronic indeterminate phase of infection. We determined: (i) the primary messenger (epinephrine and norepinephrine) levels in plasma by reverse-phase-HPLC; (ii) the cardiac ß-adrenergic receptors' (ß-AR) density and affinity by binding with tritiated dihidroalprenolol and by immunofluorescence; (iii) the cardiac concentration of the second messenger (cAMP) (by ELISA) given its importance for the phosphorylation of the proteins involved in cardiac contraction; (iv) the cardiac contractility and functional studies of the ß-ARs as a response to the ligand binding to the receptor; and (v) the left ventricular ejection fraction as a measure of in vivo cardiac function. Plasma catecholamines levels remained similar to those found in uninfected controls. The ß-ARs' affinity decreased in both infected groups compared with the uninfected group (P<0.05) while the receptors' density increased only in the SGO-Z12 group (P<0.01). Cyclic AMP levels were higher in both infected groups (P<0.01) relative to controls, and were higher in SGO-Z12-infected mice compared with those infected with the Tulahuen strain. However, the basal contractile force remained unchanged and the response to catecholamines only increased in the Tulahuen group (P<0.05). The left ventricular ejection fraction, on the other hand, was diminished in SGO-Z12-infected mice. Heterogeneity between T. cruzi strains determine, in the chronic indeterminate form, alterations in the signaling pathways of the ß-adrenergic system at different levels: (i) between catecholamines and the ß(1)-receptors; (ii) between the receptors' activation and the adenylyl-cyclase activation; and/or (iii) between cAMP and the contractile response.

Uso del "balón con cuchillas" para la ampliación de una comunicación interauricular restrictiva / Blade Balloon Atrial Septostomy to Enlarge a Restrictive Atrial Septal Defect

La presencia de una comunicación interauricular no restrictiva es obligatoria para mantener un gasto cardíaco adecuado o para lograr una mezcla de sangre aceptable en algunos pacientes portadores de cardiopatías congénitas complejas. Describimos un paciente en quien luego de un intento fallido de dilatación estática con balón de una comunicación interauricular restrictiva se utilizó un balón con cuchillas con éxito para su ampliación.

A nonrestrictive atrial septal defect is mandatory in order to maintain an adequate cardiac output or to achieve an acceptable blood mixing in some patients with complex congenital heart defects. We successfully performed a blade balloon septostomy in a patient with a restrictive atrial septal defect who had previously undergone a failed static balloon dilation of the atrial septum.

Ligadura quirúrgica del conducto arterioso permeable por miitoracotomía / Surgical ligation of patent ductus arteriosus through a mini-thoracotomy

El propósito de este estudio fue comparar la toracotomía convencional realizada para la ligadura quirúrgica del conducto arterioso permeable con una que llamaremos minitoracotomía, cuya longitud es menor.Población, material y métodos. Desde noviembre de2000 hasta setiembre de 2002 se realizó ligadura quirúrgica de conducto arterioso permeable en 30 pacientes (15 con cada tipo de toracotomía). Los grupos fueron comparables (homogéneos) con respecto a edad, sexo, peso y superficie corporal al momento de la cirugía y distancia desde su domicilio hasta nuestra institución. Luego se procedió acomparar el tamaño de la incisión y la duración dela hospitalización. Valores hallados de p ≤ 0,05 se consideraron significativos. Resultados. La longitud de la incisión y la duración de la hospitalización fueron significativamente menores en los pacientes operados con minitoracotomía(p 0,0001, p < 0,003, respectivamente). Todos los pacientes fueron extubados al concluir el procedimiento y admitidos en la Unidad de Cuidados Intensivos al menos por 24 horas. Se colocaron tubos de drenaje pleural en todos los pacientes excepto en tres que pesaban menos de 5 kg en el grupo de toracotomía convencional y en ningún paciente del grupo operado con minitoracotomía. Conclusiones. Los autores hemos identificado los beneficios en términos de estadía hospitalaria conla utilización de minitoracotomía para la ligadura quirúrgica del conducto arterioso permeable.