Hospital Ramos Mejía

La duración del período refractario anterógrado del haz anómalo es decisiva para determinar la respuesta ventricular y el riesgo potencial de fibrilación ventricular en pacientes con el síndrome de Wolff-Parkinson-White. La exploración exhaustiva de la refractariedad por estimulación auricular programada puede exteriorizar la presencia de conductividad supernormal en vías accesorias AV, durante un lapso breve y precoz del ciclo cardíaco, capaz de generar frecuencias ventriculares elevadas, aun cuando el período refractario del haz anómalo esté prolongado o la conducción anterógrada parezca abolida. En este artículo se analizan ejemplos de conductividad supernormal en haces anómalos para enfatizar su relevancia clínica potencial en pacientes con preexcitación ventricular.

IntroductionThe deep cerebral venous system plays a critical role in surgical approaches to the pineal and posterior third ventricular regions-areas that are particularly challenging in pediatric neurosurgery. While adult venous anatomy is well described, data on normal pediatric venous development remain scarce. Surgical planning in children often relies on extrapolating adult anatomy, which may not reflect age-related anatomical variations that occur during rapid brain growth.MethodsWe retrospectively analyzed high-resolution 3.0 T contrast-enhanced MRIs from 85 pediatric patients (aged 15 days-17 years) performed at a single tertiary center. Key venous angles (ICV-GV, GV-SS, SS-SSS, BV-GV) and distances (BV-BV, ICV-ICV, ICV-BV) were measured using multiplanar reconstruction. Correlations with age were assessed using Pearson correlation and linear regression. Patients were divided into three age groups (0-3 years, 4-12 years, 13-18 years), and group differences were evaluated with ANOVA and Bonferroni correction.ResultsSignificant age-related variations were identified in the conformation of the deep venous system. The ICV-GV, GV-SS, and SS-SSS angles widened with age (p < .001), while BV-GV angles decreased. BV-BV distance increased progressively from infancy to adolescence (p < .001). The ICV-BV relationship remained stable across age groups. Group comparisons confirmed significant differences between the youngest (0-3 years) and oldest (13-18 years) cohorts for most parameters.ConclusionThe venous anatomy of the pineal region evolves significantly with age. Understanding these changes can optimize preoperative planning and surgical strategies in pediatric patients. These data provide age-specific anatomical references that may support neurosurgeons worldwide, including those working in low-resource settings without routine access to neuronavigation.

Single nucleotide polymorphisms (SNPs), as common genetic variations, can influence biological processes. Identifying these variations is crucial for recognizing high-risk subgroups, guiding preventive strategies, and enabling personalized management. Objective: This study aimed to determine the relationship between SNPs and survival, thereby identifying genetic profiles associated with increased risk. Methods: We included seropositive patients with Chagas disease who had a disease duration of >20 years and no comorbidities. DNA was extracted. A SNP panel focusing on genes involved in cardiac structure was created from the GnomAD database. Patients were followed for 8 years to assess survival. The association between SNPs and survival was evaluated, and a genetic risk score was generated. Univariate and multivariate Cox regression models assessed the association between SNPs (coded as ordinal variables) and survival time. SNPs with p < 0.05 were selected to construct a risk score, which was then assessed using Kaplan-Meier curves and median survival times. Results: A total of 182 patients were included, with 96.7% completing follow-up for a median of 5.1 years (interquartile range: 3.4-6.5). The median age was 62 years; 39.6% of patients were male, and 31% had reduced left ventricular ejection fraction. Univariate analysis showed that 3 of the 68 SNPs studied were associated with survival. Variant rs3755863 (PPARGC1A gene) was significantly associated with an increased risk of death (hazard ratio, HR = 1.94; p = 0.022). Conversely, two variants, rs7310615 (SH2B3 gene) and rs7405731 (JUP gene), showed a protective effect with significantly reduced mortality risk (HR = 0.45; p = 0.006 and HR = 0.48; p = 0.006, respectively). In multivariate analysis, rs7310615 and rs7405731 remained significantly associated with survival. A genetic risk score was constructed, assigning 0 points for homozygous wild-type, 1 point for heterozygotes, and 2 points for homozygous alternative alleles. Individual scores were calculated, and survival was estimated for each score category using Kaplan-Meier analysis and median survival times. Conclusions: Two SNPs were identified as significantly associated with survival. These findings require confirmation in larger and more diverse populations. Their validation could enable the identification of a subgroup of patients at particularly high risk.

The efficacy and safety of guideline-recommended treatments for heart failure (HF) are uncertain in patients with Chagas disease. To evaluate the efficacy and safety of the angiotensin receptor-neprilysin inhibitor sacubitril/valsartan in patients with HF with reduced ejection fraction due to Chagas disease. From December 10, 2019, through September 13, 2023, patients with HF, confirmed diagnosis of Chagas disease, left ventricular ejection fraction of 40% or less, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) of 600 pg/mL or greater (or B-type natriuretic peptide [BNP] ≥150 pg/mL) or 400 pg/mL or greater (or BNP ≥100 pg/mL) if hospitalized for HF within the previous 12 months were screened at 83 sites in Argentina, Brazil, Colombia, and Mexico. Statistical analysis was conducted between May and July 2025. Patients were randomized to receive sacubitril/valsartan (target dose, 200 mg twice daily) or enalapril (target dose, 10 mg twice daily), in addition to standard therapy. The primary end point was a hierarchical composite outcome tested, in order, of death from cardiovascular causes, hospitalization for HF, or relative change in NT-proBNP from baseline to 12 weeks. The primary analysis was done using a win ratio approach. Overall, 462 participants were randomized to receive sacubitril/valsartan and 460 to receive enalapril (mean [SD] age, 64.2 [10.8] years; 387 [42.0%] were female). Over a median (IQR) follow-up of 25.2 (18.4-33.2) months, cardiovascular death occurred in 110 patients (23.8% [18.3% wins in the hierarchical comparison]) in the sacubitril/valsartan group and 117 patients (25.4% [17.5% wins]) in the enalapril group. A total of 102 patients (22.1% [7.7% wins]) in the sacubitril/valsartan group and 111 (24.1% [6.9% wins]) in the enalapril group experienced a first hospitalization for HF. Patients in the sacubitril/valsartan group had a median (IQR) decrease in NT-proBNP of 30.6% (−54.3% to −0.9%) at 12 weeks, leading to 22.5% wins, while those in the enalapril group had a 5.5% (−31.9% to 37.5%) decrease (7.2% wins). The resulting stratified win ratio was 1.52 (95% CI, 1.28-1.82; P < .001) for sacubitril/valsartan compared with enalapril. In patients with HF with reduced ejection fraction due to Chagas disease, there was no significant difference in clinical outcomes between sacubitril/valsartan and enalapril, but there was a greater reduction in NT-proBNP at 12 weeks in patients in the sacubitril/valsartan group. ClinicalTrials.gov Identifier: NCT04023227

Introducción El estado epiléptico convulsivo (EEC) constituye una urgencia neurológica de alta morbimortalidad que exige diagnóstico y tratamiento inmediatos. Ante la necesidad de actualizar las estrategias diagnósticas y terapéuticas de acuerdo con la evidencia reciente y los recursos del sistema sanitario argentino, el Grupo de Trabajo de Epilepsia de la Sociedad Neurológica Argentina (SNA) llevó a cabo una revisión narrativa y consensuada. Métodos Se conformó un panel de expertos con reconocida trayectoria clínica y académica, que revisó la literatura publicada en los últimos 10 años, priorizando ensayos clínicos, guías internacionales y revisiones sistemáticas relevantes. Los tópicos abordados incluyeron la definición, la clasificación, la fisiopatogenia, el diagnóstico y el tratamiento del EEC en los adultos, con el objetivo principal de ofrecer recomendaciones actualizadas y contextualizadas a los recursos del sistema de salud argentino, dirigidas a los profesionales involucrados en su diagnóstico y manejo. Desarrollo El documento propone un abordaje operativo y estructurado, desde la fase prehospitalaria hasta el manejo del estado refractario y superrefractario. En cada sección se destacan puntos clave destinados a facilitar la comprensión y la aplicación práctica de los lineamientos. Se enfatiza la importancia del tratamiento precoz con benzodiacepinas en dosis adecuadas, la activación de códigos de alerta y la selección de fármacos de segunda línea —como levetiracetam, ácido valproico o fenitoína— según disponibilidad y comorbilidades. En los casos refractarios, se analizan alternativas anestésicas e inmunomoduladoras. Conclusión Estas recomendaciones, adaptadas a la realidad asistencial nacional, buscan optimizar los tiempos terapéuticos, reducir complicaciones y mejorar el pronóstico de los pacientes. Este consenso constituye una actualización integral para la Argentina sobre el manejo del EEC en los adultos, y aspira a servir como referencia práctica para los profesionales de la salud, así como base para futuras investigaciones locales.