Reversible posterior leukoencephalopathy syndrome associated with left ventricular assist device.

Reversible posterior leukoencephalopathy syndrome (RPLES), previously known as posterior reversible encephalopathy syndrome (PRES), is characterized by the presence of bilateral lesions located within the posterior border zones of the cerebral hemisphere and cerebellum. This condition commonly presents with headache, nausea, vomiting, decreased vision and level of consciousness, and seizures. RPLES has been associated with hypertensive encephalopathy, eclampsia, renal failure, and immunosuppressive therapy following transplant. We report the development of RPLES in a boy following implantation of a left ventricular assist device (LVAD). To our knowledge, this is the first report of RPLES in association with the use of LVAD.

Use of peak Doppler gradient across ventricular septal defects leads to underestimation of right-sided pressures in patients with "sloped" Doppler signals.

In patients with "sloped" appearance of the Doppler signal across a ventricular septal defect (VSD), the peak Doppler velocity seems to overestimate the catheterization-derived peak-to-peak gradient, resulting in underestimation of right-sided heart pressures. In 11 patients with sloped Doppler signals across the VSD, ventricular pressure tracings were compared with simultaneous recordings of the Doppler signal. The average peak Doppler gradient (40.2 +/- 19.2 mm Hg) overestimated the catheterization-derived peak-to-peak gradient (20.2 +/- 13.6 mm Hg) significantly (P < or =.001). Doppler mean gradient (20.2 +/- 11.3 mm Hg; P = ns) and end-systolic gradient (17.0 +/- 12.5 mm Hg; P < or =.05) were closer estimates of the catheterization peak-to-peak gradient. All Doppler gradients showed good correlation to the catheterization peak-to-peak gradient with r2 values of 0.77, 0.73, and 0.91. We conclude that Doppler mean or end-systolic gradients should be used for calculation of right-sided heart pressures in this patient population.

Second-line treatment of fetal supraventricular tachycardia using flecainide acetate.

Digoxin has been an effective treatment for fetal supraventricular tachycardia (SVT), but second-line therapy remains more controversial. Thirty-seven cases of fetal SVT were identified that received digoxin as first-line therapy. Seventeen fetuses (46%) converted to and maintained normal sinus rhythm. Flecainide was used in 13/15 patients requiring second-line therapy; 12/13 (92%) converted to sinus rhythm. Of seven hydropic fetuses, five required second-line therapy and were then successfully converted with flecainide. The improved efficacy of flecainide was statistically significant with a p value <0.01. Complete follow-up was available in 13 digoxin-treated and in 12 second-line therapy infants. Prolonged or multiple drug therapy for postnatal arrhythmia management was required in 3/13 (23%) patients in the digoxin group and in 8/12 (67%) patients requiring second-line therapy. This demonstrated a correlation between the need for second-line fetal therapy and more complex postnatal management with a p value of 0.003. Digoxin remains an effective first-line therapy in the treatment of fetal SVT. Flecainide is an effective second-line therapy, especially in the face of fetal hydrops. Use of second-line therapy in fetal SVT is a predictor of complex postnatal course, and these patients should be followed more closely.

Retrieval of "old" foreign bodies from the cardiovascular system in children.

Several techniques have been developed to retrieve catheter and guide wire fragments that have embolized to the heart and pulmonary vasculature. In most instances, retrieval of the embolized fragments is performed soon after the event has occurred. In this report, we summarize our experience with the removal of these fragments in 3 children after a significant amount of time had elapsed since the time of embolization. The embolized catheter and guide wire fragments were removed without any complications. We also describe the techniques used for their removal, and the problems encountered during the removal of these "old" foreign bodies.

Controlled prospective randomized comparison of high-frequency jet ventilation and conventional ventilation in neonates with respiratory failure and persistent pulmonary hypertension.

OBJECTIVE: The objective of this study was to evaluate the efficacy and safety of high-frequency jet ventilation in near-term and term neonates with persistent pulmonary hypertension. STUDY DESIGN: Subjects for this prospective, randomized, controlled comparison study were recruited from neonates treated in a level-three neonatal intensive care unit that accepts referrals for extracorporeal membrane oxygenation. RESULTS: In patients treated with high-frequency jet ventilation (n = 11) acute improvement in oxygenation (p = 0.008), ventilation (p < 0.001), and oxygen indices (p < or = 0.01) was demonstrated while stable peak and mean airway pressures were maintained. Control group patients receiving high-frequency positive pressure ventilation with a conventional ventilator required increasingly higher peak inspiratory pressures (p = 0.005) to maintain oxygenation, ventilation, and oxygen indices. There were no significant differences in survival without use of extracorporeal membrane oxygenation, nor were there differences in duration of oxygen therapy, ventilation, and hospitalization; need for extracorporeal membrane oxygenation; or incidence of chronic lung disease. CONCLUSIONS: High-frequency jet ventilation acutely improves oxygenation and ventilation without significantly increasing morbidity. Therefore high-frequency jet ventilation may be a useful adjunct for stabilization of the conditions of neonates with severe persistent pulmonary hypertension. Conclusions about the efficacy of high-frequency jet ventilation in improving survival without the need for extracorporeal membrane oxygenation await multicentered, collaborative investigations with large cohorts of patients.

Doppler derivation of complete pulmonary artery pressure curves in patent ductus arteriosus.

Doppler echocardiography can be used in patients with a patent ductus arteriosus to generate complete pulmonary artery pressure curves. This technique provides a dynamic evaluation of changes in pulmonary artery pressures throughout the cardiac cycle and provides more hemodynamic information than single-point Doppler velocity methods of estimating pulmonary artery pressures.

Surgical management of hypoplastic left heart syndrome.

BACKGROUND: The treatment of infants with hypoplastic left heart syndrome has been challenging and controversial. METHODS: To assess the operative management and intermediate-term outcome, we retrospectively analyzed our surgical experience with 50 newborns with hypoplastic left heart syndrome operated on between January 1989 and June 1995. RESULTS: Surgical palliation with a first-stage Norwood operation was offered to 28 patients. The remaining 22 infants were initially listed for heart transplantation, and 15 underwent the operation. Ten of the 15 recipients are alive, and all are in New York Heart Association class I. Seven infants underwent a Norwood procedure after being on the list for transplantation for 12 to 42 days. A total of 34 patients underwent Norwood procedures with one operation aborted because of inoperable anatomy. Two infants who survived the first-stage Norwood operation underwent subsequent heart transplantation and are currently doing well. The 1-year mortality rate for heart transplantation was 18% (3/17) versus 50% (17/34) for the Norwood procedure. Risk factors for early mortality after a Norwood procedure include longer circulatory arrest time (> 50 minutes), preoperative acidosis (pH < 7.20), larger systemic-pulmonary artery shunt (> or = 4 mm), diminutive ascending aorta (< or = 2.0 mm), and anatomic subtype of aortic and mitral atresia. The 1-year survival rate for the Norwood procedure improved from 36% for the patients operated on during 1989 through 1992 to 75% during 1993 to mid-1995 (p = 0.005). Of the 17 survivors of a first-stage Norwood operation, 10 have undergone the second stage (bidirectional Glenn procedure), and 7 have completed a Fontan procedure. Heart transplantation results have also improved, with no deaths since 1992. CONCLUSIONS: Both the Norwood procedure and heart transplantation have encouraging early to intermediate results in infants with hypoplastic left heart syndrome. Hypoplastic left heart syndrome should be managed selectively on the basis of cardiac morphology, donor availability, and family wishes. Development of a flexible program involving the use of both procedures may aid in the successful management of infants with hypoplastic left heart syndrome.

Short-term survivors of pediatric heart transplantation: an autopsy study of their pulmonary vascular disease.

BACKGROUND: The most common indications for heart transplantation in children are congenital heart disease and cardiomyopathy. Intracardiac lesions that vary widely in morphology may have a similar impact on pulmonary vascular morphology; for example, any lesion that increases left-sided intracardiac pressure will affect pulmonary venous pressure and morphology and, if long-standing, may affect pulmonary arteries also. METHODS: The lungs of eight children who died 2 days to 7 months after receiving a heart transplant at ages 8 days to 4 years were examined at autopsy with particular regard to the pulmonary arteries and veins. Arteries were evaluated for medial thickness, intimal proliferation, and peripheral extension of muscle; veins for medial thickness and mural elastic tissue configuration; and lymphatics for degree of dilation. RESULTS: The main pulmonary arteries of the children with congenital heart disease showed an abnormal elastic tissue pattern, similar to the pattern of the aorta, indicating that pulmonary arterial hypertension was present in these children at birth. In contrast, the pulmonary trunk of a child who had myocarditis beginning at age 2 years had a normal pulmonary elastic tissue pattern, consistent with normal neonatal pulmonary pressure. Five children with morphologic evidence of early pulmonary arterial hypertension had a left-to-right atrial shunt before the operation and elevated pulmonary artery pressure immediately after transplantation. The pulmonary arteries of all five patients had medial hypertrophy or peripheral extension of muscle; the most advanced pathologic condition occurred in the arteries of the oldest child, who was 5 months of age, at the time of transplantation who died 2 days after the operation with pulmonary arterial hypertension. In the lungs of all eight patients, pulmonary veins showed medial hypertrophy and excess elastic tissue fibers (arterialization), consistent with venous hypertension. The most impressive venous changes in the lungs of the children with hypoplastic left heart syndrome occurred in the two children who had the smallest left ventricles (4 x 6 mm and 8 x 8 mm), and in another child with hypoplastic and anomalous extrapulmonary pulmonary veins. The most impressive lymphangiectasis occurred in the lungs of the child with hypoplastic left heart syndrome who was oldest at the time of transplantation and in the lungs of a child with obstructed venous drainage. CONCLUSIONS: Pulmonary vasculopathy in children who require heart transplantation because of congenital heart disease or long-standing congestive heart failure may involve arteries, veins, and lymphatics. Among the eight patients in this autopsy study of children who died less than a year after heart transplantation, arterial vasculopathy associated with congenital heart disease appeared more pronounced in the five who survived less than 30 days compared with the two longer survivors. The lack of morphologic progression in short-term survivors of pulmonary arterial vasculopathy after heart transplantation correlates with clinical follow-up of long-term survivors who do not have problematic pulmonary arterial hypertension. Pulmonary venous vasculopathy is determined by the degree of pretransplantation left-sided obstruction caused by congenital or acquired disease and may be more persistent morphologically than arterial vasculopathy. This morphologic study of the pulmonary vasculature of short-term survivors of heart transplantation supports the concept that palliative surgical procedures may benefit children awaiting heart transplantation, especially infants with hypoplastic left heart syndrome for whom suitable donors are scarce.

Rings, slings and such things: diagnosis and management with special emphasis on the role of echocardiography.

Vascular anomalies of the aorta and pulmonary artery that cause tracheal, esophageal, or tracheoesophageal compression form an important group of congenital cardiovascular malformations. The diagnostic approach to the patient with possible vascular ring is variable. This article presents a systematic approach to the evaluation and management of this fascinating group of malformations, with special emphasis on the role and limitations of echocardiography. Using this approach between September 1990 and March 1992, we identified and defined vascular anomalies of aorta and pulmonary artery in eight children.