Electromechanical Dyssynchrony Is Associated With Right Ventricular Remodeling and Dysfunction Independently of Pulmonary Regurgitation Late After Tetralogy of Fallot Repair.

BACKGROUND: The aim of this study was to investigate the relationship among right ventricular (RV) dilatation, dysfunction, and electromechanical dyssynchrony (EMD) in patients with repaired tetralogy of Fallot (rTOF). METHODS: Data from a prospective rTOF registry of subjects with moderate or greater pulmonary regurgitation (PR) and contemporary imaging were analyzed. Electrocardiograms and echocardiograms were analyzed for EMD (prolonged QRS duration [QRSd], echocardiographic septal flash, and mechanical delay) and mechanical dispersion. The relationship among these, RV measurements on cardiac magnetic resonance, exercise capacity, and incident arrhythmia or death was analyzed with adjustment for PR. RESULTS: In total, 271 patients with rTOF (42% women; median age, 32 years; interquartile range [IQR], 23-34 years) were included. Patients had moderate to severe PR (median PR fraction, 38%; IQR, 30%-47%), moderate to severe RV enlargement (median RV end-diastolic volume index, 161 mL/m2; IQR, 138-186 mL/m2) and mild RV systolic dysfunction (median RV ejection fraction [RVEF], 44%; IQR, 38%-48%). Eleven patients (4%) experienced ventricular arrhythmia or death. Presence of EMD was associated with larger RV size (RV end-diastolic volume index and RV end-systolic volume index, P = .006 and P < .001, respectively) and lower RVEF (P < .001). A sharp inflection in the relation among QRSd, RV size, and RVEF was observed when QRSd exceeded 150 msec (3.1% decrease in RVEF for every 20-msec increase in QRSd between 160 and 200 msec). Similar inflection points were observed for the mechanical delay between the RV basal-lateral and midseptal segments. The mechanical delay was higher in patients with vs without incident atrial arrhythmia (371 vs 276 msec, P = .014). CONCLUSIONS: In adults with rTOF, EMD is independently associated with larger RV size, lower RVEF, and incident atrial arrhythmias.

Tetralogy of Fallot Across the Lifespan: A Focus on the Right Ventricle.

Tetralogy of Fallot is a cyanotic congenital heart disease, for which various surgical techniques allow patients to survive to adulthood. Currently, the natural history of corrected tetralogy of Fallot is underlined by progressive right ventricular (RV) failure due to pulmonic regurgitation and other residual lesions. The underlying cellular mechanisms that lead to RV failure from chronic volume overload are characterized by microvascular and mitochondrial dysfunction through various regulatory molecules. On a clinical level, these cardiac alterations are commonly manifested as exercise intolerance. The degree of exercise intolerance can be objectified and aid in prognostication through cardiopulmonary exercise testing. The timing for reintervention on residual lesions contributing to RV volume overload remains controversial; however, interval assessment of cardiac function and volumes by echocardiography and magnetic resonance imaging may be helpful. In patients who develop clinically important RV failure, clinicians should aim to maintain a euvolemic state through the use of diuretics while paying particular attention to preload and kidney function. In patients who develop signs of cardiogenic shock from right heart failure, stabilization through the use of inotropes and pressor is indicated. In special circumstances, the use of mechanical support may be appropriate. However, cardiologists should pay particular attention to residual lesions that may impact the efficacy of the selected device.

De nombreuses techniques chirurgicales permettent aux patients présentant une tétralogie de Fallot (TF), une forme de cardiopathie congénitale, de survivre jusqu'à l'âge adulte. À l'heure actuelle, l'évolution naturelle de la TF corrigée est caractérisée par une insuffisance ventriculaire droite (VD) progressive attribuable à une régurgitation pulmonaire et à d'autres lésions résiduelles. Les mécanismes cellulaires sous-jacents qui mènent à l'insuffisance VD due à une surcharge volumique chronique sont caractérisés par une dysfonction microvasculaire et mitochondriale faisant intervenir diverses molécules régulatrices. Sur le plan clinique, ces atteintes cardiaques se manifestent par une intolérance à l'effort qui peut être évaluée au moyen d'une épreuve d'effort cardiorespiratoire, ce qui permet de faciliter l'établissement d'un pronostic. Le moment propice pour une réintervention en cas de lésions résiduelles contribuant à la surcharge volumique du ventricule droit demeure controversé; toutefois, il peut être utile d'évaluer régulièrement la fonction et les volumes cardiaques au moyen d'une échocardiographie et de tests d'imagerie par résonance magnétique. En présence d'une insuffisance VD cliniquement importante, les cliniciens doivent tenter de maintenir les patients dans un état euvolémique en utilisant des diurétiques, tout en accordant une attention particulière à la précharge et à la fonction rénale. Si les patients manifestent des signes de choc cardiogénique associé à une insuffisance cardiaque droite, il convient de leur administrer des inotropes et des vasopresseurs pour stabiliser leur état. Dans certains cas, l'utilisation d'un dispositif d'assistance mécanique peut être appropriée. Cependant, les cardiologues doivent être attentifs aux lésions résiduelles, car elles peuvent influencer l'efficacité de ce dispositif.

Pediatric Intraosseous Access Performed by Emergency Department Nurses Using Semiautomatic Devices: A Randomized Crossover Simulation Study.

BACKGROUND: No study has examined the performance of emergency department (ED) nurses in establishing intraosseous access (IO) access. This study aimed to evaluate ED nurses' success rate in establishing pediatric IO access using semiautomatic devices. METHODS: A randomized crossover simulation study was conducted. The success rates of ED nurses were compared with those of paramedics with similar years of experience. The study instruments were the new spring-loaded injector (NIO) and the battery power drill (EZ-IO). Uncooked piglets' bones were used as the study model. All attempts were filmed by a video camera. Successful placement was defined as the visualization of flow from the marrow cavity. Participants recorded their ranking of the "ease of use" of each device. RESULTS: No differences in 1-attempt success rate was found between nurses and paramedics (27/34 [79.4%] vs 25/30 [83.3%], P = 0.68). Nurses and paramedics had similar success rates with the 2 semiautomatic IO devices (12/17 vs 12/15 with the spring-loaded injector, P = 0.69, and 15/17 vs 13/15 with the battery power drill, P = 0.9). The number of failed attempts and the causes for failure were equally distributed between nurses and paramedics. Median ease-of-use Likert-scale scores of the spring-loaded injector and the battery power drill were 4 (interquartile range [IQR] = 3-4) and 5 (IQR = 5-5) (P < 0.04) for the nurses and 5 (IQR = 4-5) and 5 (IQR = 4-5) (P = 0.44) for the paramedics, respectively. CONCLUSIONS: Emergency department nurses and paramedics had a similarly high insertion success rates on a pediatric bone model. This pilot study suggests that ED nurses can successfully perform this procedure.

Methylene Blue Administration for Distributive Shock States in Critically Ill Children.

BACKGROUND: Methylene blue (MB), an inhibitor of nitric oxide synthesis and its effects is a potentially effective treatment against distributive shock states such as septic shock and vasoplegic syndrome. MB has been shown to alleviate vasoplegia and promote an increase in blood pressure. It may reduce mortality. However, in the pediatric population, there are few case reports and only one controlled study on administration of MB use for vasoplegia, sepsis, or shock in general. OBJECTIVES: To summarize the experience of administering MB for vasoplegic shock in a tertiary care pediatric intensive care unit. METHODS: A retrospective chart review of seven pediatric cases treated with MB for vasoplegic shock was conducted. MB was administered as a bolus followed by continuous infusion. The authors measured blood pressure, vasopressor, and inotropic support. Patient outcome was monitored. RESULTS: The authors observed a favorable hemodynamic response with an increase in blood pressure and a reduction in vasopressor and inotropic support needed following MB administration in six patients. No side effects were observed. Three patients eventually died one to two days later, secondary to their underlying disease. CONCLUSIONS: This case series adds to the small body of evidence in the pediatric population supporting the use of MB for distributive shock states and emphasizes the need for larger, randomized trials evaluating its role in vasoplegic shock treatment.

VV extracorporeal life support for the Third Millennium: will we need anticoagulation?

Since the late 1600's medicine and science have entertained the idea of extracorporeal circulation. With this technology to allow for cardiac and pulmonary support came the development of anticoagulation. Although this advanced the technology and capabilities of extracorporeal life support, it was not without complications and risks. The most common complications in extracorporeal life support (ECLS) present day are related to hemorrhage and thrombus due to the need for systemic anticoagulation and the challenges associated with it. This review focuses on present day techniques for anticoagulation for ECLS and what future surface modifications may do to obviate the use of systemic anticoagulation entirely.

Role 1 Pediatric Trauma Care on the Israeli-Syrian Border-First Year of the Humanitarian Effort.

BACKGROUND: This article summarizes the experience with Role 1 care for 135 Syrian children who received medical care during the year 2013 as part of an ongoing humanitarian effort. METHODS: The database included demographic information, point-of-injury assessment and outcome, and was analyzed using SPSS. RESULTS: Trauma casualties were the majority of the group (84 cases), and mostly male. Almost one-third of casualties arrived more than 6 hours after injury, and time of injury was unknown in another third. The most common mechanism of injury was shrapnel (51.2%), followed by gunshot wounds (22.6%). Gunshot wound victims were significantly older than shrapnel and artillery victims (p < 0.01, < 0.05, respectively). Only 14 cases (14.28%) underwent previous interventions in Syria. Most of the casualties (44 cases, 52.4%) underwent at least one procedure during Role 1 treatment with a high overall success rate (93.18%) that was not correlated to Advanced Life Support provider type (physician [MD], emergency medical technician-paramedic, or both). Mortality was low (3 cases). CONCLUSION: The study cohort exhibits several unique features, including a delay in arrival to medical care, paucity of prior care and information, and the specific mechanisms of injury. Our study suggests that Advanced Life Support providers do not differ significantly in Role 1 treatment choices and procedure success.