RESUMO
INTRODUCTION: Dual atrioventricular (AV) nodal physiology, defined as an AH jump > or =50 msec with a 10 msec decrease in A1A2, is the substrate for atrioventricular nodal reentrant tachycardia (AVNRT) and yet it is present in a minority of pediatric patients with AVNRT. Our objective was to characterize dual AV nodal physiology as it pertains to a pediatric population. METHODS/RESULTS: We retrospectively reviewed invasive electrophysiology studies in 92 patients with AVNRT (age12.1 +/- 3.7 yrs) and in 46 controls without AVNRT (age 13.3 +/- 3.7 yrs). Diagnoses in controls: syncope (N = 31), palpitations (N = 6), atrial flutter (N = 3), history of atrial tachycardia with no inducible arrhythmia (N = 3), and ventricular tachycardia (N = 3). General anesthesia was used in 49% of AVNRT and 52% of controls, P = 0.86. There were no differences in PR, AH, HV, or AV block cycle length. With A1A2 atrial stimulation, AVNRT patients had a significantly longer maximum AH achieved (324 +/- 104 msec vs 255 +/- 67 msec, P = 0.001), and a shorter AVNERP (276 +/- 49 msec vs 313 +/- 68 msec P = 0.0005). An AH jump > or =50 msec was found in 42% of AVNRT versus 30% of controls (P = 0.2). Using a ROC graph we found that an AH jump of any size is a poor predictor of AVNRT. With atrial overdrive pacing, PR > or = RR was seen more commonly in AVNRT versus controls, (55/91(60%) vs 6/46 (13%) P = 0.000). CONCLUSIONS: Neither the common definition of dual AV nodes or redefining an AH jump as some value <50 msec are reliable methods to define dual AV nodes or to predict AVNRT in pediatric patients. PR > or = RR is a relatively good predictor of AVNRT.
Assuntos
Nó Atrioventricular/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Taquicardia por Reentrada no Nó Atrioventricular/fisiopatologia , Adolescente , Criança , Técnicas Eletrofisiológicas Cardíacas , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Taquicardia por Reentrada no Nó Atrioventricular/diagnóstico , Fatores de TempoRESUMO
Umbilical artery catheterization is often performed in critically ill neonates. Infection and thromboembolic events are relatively frequent complications, but aneurysm formation is rare. We describe the case of a premature baby who developed a rapidly expanding aneurysm of the descending thoracic aorta, secondary to a highly placed infected umbilical catheter. The rapid progression under medical therapy prompted us to replace the thoracic aorta with an 8-mm polytetrafluoroethylene graft, using extracorporeal circulation and core cooling. The baby had an excellent recovery and was discharged home after a prolonged antibiotic course. He is being followed with repeated imaging studies for a small abdominal aneurysm. We describe a novel approach to this rare and complicated problem and provide a review of the literature on the subject.
Assuntos
Aneurisma da Aorta Torácica/microbiologia , Cateterismo/efeitos adversos , Artérias Umbilicais , Antibacterianos/uso terapêutico , Aneurisma da Aorta Torácica/tratamento farmacológico , Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , MasculinoRESUMO
A large intrapericardial mass was incidentally found in a fetus at 32 weeks gestational age, which was accompanied by a significant pericardial effusion. The baby was delivered by cesarean section and had surgical removal of the tumor on the second day of life. Alpha-fetoprotein was elevated. The pathologic analysis demonstrated a grade I immature teratoma with foci of hepatoid tissue. The patient had an uneventful postoperative recovery. A review of the literature and pathologic implications are discussed.