Showing papers in "Pediatric Cardiology in 1999"

Congenital heart disease among 815,569 children born between 1980 and 1990 and their 15-year survival: a prospective Bohemia survival study.

Abstract: The objective of this study was to ascertain the prevalence and survival rate of children born with a heart defect. A total of 816,569 children live-born between 1980 and 1990 in Bohemia (52,478 km2, population 6.314 million, western Czech Republic) were followed up and those with suspected heart disease referred to a center. Echocardiography was done in all of them. All dead children were autopsied. Congenital heart disease was found in 5030 of 816,569 children (6.16 per 1000 live births). The most frequent conditions were ventricular septal defect (41.59%), atrial septal defect (8.67%), aortic (7.77%) and pulmonary (5.81%) stenoses, transposition of the great arteries (5.39%), coarctation of the aorta (5.29%) and persistent ductus arteriosus (5.07%). The first week was survived by 92.46%, the first month by 89.14%, 6 months by 82.42%, and the first year of life by 80.02%, and 77.11% (95% CI 75.91–78.31%) survived to age 15 years. The best prognosis was found in pulmonary stenosis (15-year survival 95.55%), atrial septal defect (92.04%), persistent ductus arteriosus (90.59%), ventricular septal defect (89.37%) and aortic stenosis (88.39%). The worst results were attained in hypoplastic left heart, truncus arteriosus and pulmonary atresia with intact ventricular septum. In conclusion, the prevalence of congenital heart disease was 6.16 per 1000 live births; 77.11% of patients survived to age 15 years.

Dentists are innocent! "Everyday" bacteremia is the real culprit: a review and assessment of the evidence that dental surgical procedures are a principal cause of bacterial endocarditis in children

Abstract: The literature related to three aspects of dental bacteremia has been reviewed in regard to postprocedure bleeding and bacteremia, intensity of bacteremia, and cumulative exposure to bacteremia from ``everyday'' events. The data on postprocedure bleeding and bacteremia show that there is no relationship between bleeding and bacteremia. Significant bacteremia can occur in the absence of clinically discernible bleeding. The intensity of bacteremia in humans is significantly less than that used in experimental endocarditis models. It is unlikely that the intensity of bacteremia following dental procedures in children could readily lead to endocarditis. The cumulative exposure to bacteremia is significantly greater from everyday procedures when compared to dental operative procedures. It is far more likely that such everyday procedures are the cause of bacterial endocarditis because the cumulative exposure is often hundreds, thousands, or even millions of times greater than that occurring following surgical procedures such as extraction of teeth. The value of antibiotic prophylaxis prior to dental treatment is questioned.

Aortic Arch Anomalies Associated with Chromosome 22q11 Deletion (CATCH 22)

Abstract: Chromosome 22q11 deletion or CATCH 22 is associated with DiGeorge syndrome, conotruncal anomaly face syndrome, and velocardiofacial syndrome. Associated congenital heart diseases include tetralogy of Fallot, truncus arteriosus, and ventricular septal defect. Associated anomalies of the aortic arch, aortic branches, ductus arteriosus, and pulmonary arteries are more frequent in patients with the deletion than in those without the deletion. Associated anomalies include right aortic arch, cervical aorta, aberrant origin or isolation of the subclavian artery, the absence of the ductus arteriosus, major aortopulmonary collateral arteries, isolation of the left pulmonary artery, and vascular ring formed by the right aortic arch, retroesophageal aortic arch, and left descending aorta.

Complement Activation, Cytokines, and Adhesion Molecules in Children Undergoing Cardiac Surgery with or without Cardiopulmonary Bypass

Abstract: The effect of cardiopulmonary bypass (CPB) on various blood parameters in children undergoing major cardiovascular surgery was investigated in a prospective clinical study. Blood samples of children with CPB (CPB group, n = 18) or without CPB (control, n = 12) were collected before, during, and after surgery. The concentration of routine laboratory parameters, components of the complement system (C3, C4, C5, C1 inhibitor, total hemolytic complement, C3d, and C5a), circulating interleukins (IL-6 and IL-8) and soluble adhesion molecules (sICAM-1 and sE-selectin) were determined. In both groups of patients the serum concentrations of C3, C4, C5, and C1 inhibitor were significantly affected by the treatments (p < 0.001), decreased immediately after onset of anesthesia, were minimal during surgery, and increased thereafter. No significant differences in the kinetics of these parameters were detectable between CPB and control group. In the CPB group the activation of the alternative pathway (increased C3d) was found to be a specific response (p = 0.005), but also in the control group C3d and C5a concentration increased significantly (p < 0.022), indicating complement activation. None of the effects that would be expected after activation of the complement system were specific for the CPB group. In both groups the serum levels of IL-6 increased dramatically during and/or after surgery (p = 0.001), and IL-8 was detectable after surgery in 10/12 control patients. The concentration of sICAM-1 and sE-selectin decreased during surgery (p < 0.04) and later did not increase above baseline. Our data suggest that increased serum levels of inflammation mediators and increased consumption of complement and adhesion molecules occur during cardiovascular surgery. Although complement activation and ICAM-1 consumption are more pronounced in the CPB patients, none of these changes occurs exclusively in the CPB group. We conclude, therefore, that these changes are the combined effect of anesthesia, surgical trauma, and endothelial lesions. Additional, undefined CPB-induced reactions may also contribute the postoperative morbidity.

Cardiac functions in children with vitamin D deficiency rickets.

Abstract: Nutritional deficiency of vitamin D is common in developing countries as a result of both inadequate diet and exposure to ultraviolet light. The most striking biochemical finding in this illness is hypocalcemia. Reduction in serum calcium level may affect ventricular contraction. The purpose of this study was to evaluate prospectively left ventricular function in a group of 27 infants diagnosed as having rickets. Electrocardiograms and echocardiographic studies were undertaken in all patients. A group of ten healthy infants was used as a control for the echocardiographic examinations. Patients were divided into three groups according to the biochemical classification of rickets. There were eight patients in group I, nine in group II, and ten in group III. Abnormal electrocardiographic findings were noted in four infants in group I, three in group II, and six in group III before treatment of the rickets. These changes resolved following treatment. Echocardiographic studies revealed left ventricular dysfunction in the pretreatment stage. The most striking echocardiographic finding is the increase in the ratio of interventricular septal thickness to left ventricular posterior wall thickness in eight patients from group III. This returned to normal after treatment of the rickets. This study has demonstrated echocardiographic evidence of left ventricular dysfunction in children with rickets. These abnormalities were not, however, sufficiently severe to be associated with clinical signs of cardiac failure. Cardiomyopathy may develop in rickets, especially in the third stage of the disease, and this finding may return to normal following adequate treatment of the rickets.

Exercise Studies in Tetralogy of Fallot: A Review

Abstract: Exercise evaluation of patients with congenital heart disease in general and tetralogy of Fallot in particular has had much less impact on clinical care than that of adults with coronary heart disease. Of over 4000 references on tetralogy of Fallot in the literature since 1965, only 87 involve exercise. These studies were reported from 56 institutions, with 39 originating from the United States and Canada, 40 from Europe, and 8 from Japan. They involved 3157 patients, studied mostly after intracardiac repair (ICR). In reviewing these data one is struck by the wide range of different approaches to exercise testing. This is in part related to the different purposes of each exercise study, but it also relates to the lack of uniform standards for exercise testing in patients with congenital heart disease. The studies involved maximal treadmill exercise and maximal or submaximal cycle ergometer work, in the upright or supine position, utilizing 52 different work protocols, the most common being the Bruce treadmill protocol (employed 27 times). Despite this lack of standardization exercise evaluation has significantly contributed understanding of the natural history and pathophysiology of surgically corrected tetralogy of Fallot.

Turner's syndrome: cardiologic profile according to the different chromosomal patterns and long-term clinical follow-up of 136 nonpreselected patients

Abstract: The preferential association between Turner's syndrome and congenital heart defects (CHD) have been well known since the first description by Morgagni. There are few studies about the different cardiologic problems stemming from different chromosomal patterns of X monosomies. We reviewed a large series of 136 patients with Turner syndrome without cardiologic preselection, 29 of whom had some kind of CHD (21.5%). Partial anomalous pulmonary venous drainage (PAPVD; 2.9%), aortic valve disease (stenosis and/or incompetence) (AoVD; 5.1%), aortic coarctation (AoCo; 4.4%), and bicuspid aortic valve (BicAo; 14.7%) are much more frequent in Turner's syndrome than in the normal population, with the difference being statistically highly significant. In our cases, only the 45, X subjects showed severe CHD and multiple lesions, whereas the X-ring pattern was associated with an elevated prevalence of BicAo. Patients with X-deletion showed no signs of congenital heart malformations. Eleven patients, all with 45, X pattern, and significant CHD, underwent cardiac surgery at a mean age of 7.7 ± 5.3 years (range 7 days–18 years) without complications. At follow-up of 3–18 years (8.6 ± 5.2), we were unable to observe any type of evolution of the remaining untreated cardiovascular anomalies.

Results of Surgical Treatment of Congenital Heart Defects in Children with Down's Syndrome

Abstract: We analyzed early and late results of surgical treatment of 100 consecutive children with Down's syndrome (DS) and congenital heart defect (CHD) who were operated on between 1990 and 1997. Fifty had common atrioventricular canal (CAVC), 24 ventricular septal defect, 8 the ostium primum atrial septal defect, 8 tetralogy of Fallot (TOF), 3 patent ductus arteriosus, 3 the ostium secundum atrial septal defect, and 4 CAVC coexisting with TOF. In 93 patients total correction was performed. The total death rate was 6%. Death in the CAVC group was 8%, but it decreased to 2.7% during the past 3 years. The children who were followed up (from 7 months to 6 years; mean, 39 months) are in NYHA class I or II. There were no reoperations. The postoperative course was complicated by pulmonary infections in 38% of patients, which converted to generalized infection in 10% and was the cause of death in 8% of patients. These results indicate that CHD in DS children can be repaired with a low death rate and low incidence of severe mitral atrioventricular valve regurgitation in the CAVC group. A high incidence of severe infections can influence the final results. Repair of CHD in infancy helps to eliminate problems connected with congestive heart failure and pulmonary hypertension.

Exercise studies in patients with transposition of the great arteries after atrial repair operations (Mustard/Senning): a review.

Abstract: Exercise evaluation studies of patients after atrial repair surgery for transposition of the great arteries, as in tetralogy of Fallot, represent only a small fraction of the 3970 Medline references (1966 to mid-1997) concerning this congenital heart lesion. We have abstracted data from 27 studies from 20 institutions reporting on measurements during exercise on work capacity, heart rate response, respiratory gas exchange, or radionuclide/radiographic systemic ventricular ejection fraction measurements in addition to resting pulmonary function measurements. These studies provide almost uniform general conclusions that even after 20 or more years of follow-up (1) most patients ``report'' that they are asymptomatic in performing usual levels of physical activities; (2) significant abnormalities are present, often in more than half of the patients studied, in one or more of the exercise measurements when compared to control subjects; and (3) the diminished exercise performance is related to a diminished cardiac output, results from diminished stroke volume but is also related to a blunted heart rate response.

Spontaneous closure of atrial septal defects.

Abstract: Atrial septal defects (ASDs) are found more frequently in the pediatric population than in adults, and improved diagnostic techniques with echocardiography (2DE) and Doppler facilitate diagnosis so that repair is possible at an optimal time. The purpose of our investigation was to study the size of ASDs at diagnosis, how size changes during follow-up, and to explore the relationship between size at diagnosis and need for surgery. We reviewed the medical records of all patients in Iceland with the diagnosis of ASD born between 1984 and 1993. ASD was confirmed by 2DE in all patients and defects smaller than 4 mm were excluded. ASD size was measured by 2DE from subxyphoid long and short axis views. There were 91 patients-29 males and 62 females. Four patients died from causes other than the heart defect and had not been operated upon. Seven patients with ASD primum and sinus venosus defects were excluded from analysis. There were 29 patients with a 4 mm defect, 17 patients with 5 or 6 mm defects, 8 patients with 7 or 8 mm defects, and 26 patients had defects >8 mm. In the 4 mm group, in 26 patients (89%) the ASD closed spontaneously or decreased in size, and 1 patient had been operated upon. In the 5 or 6 mm group, 15 of 19 ASDs (79%) had closed spontaneously, and 2 patients (9.5%) had been operated upon. In the 7 or 8 mm group, 1 of 6 ASDs (16.6%) had closed spontaneously and 3 had been closed surgically. In the >8 mm group, 1 of 24 ASDs had closed spontaneously and 20 (91%) had been closed surgically. We conclude that defects smaller than 6 mm in diameter are very likely to close spontaneously although follow-up is necessary. Defects larger than 8 mm have a high probability requiring operative closure.

Epidemiology, Etiology, and Management of Kawasaki Disease: State of the Art

Abstract: Since its first description in Japan 30 years ago, Kawasaki disease has been reported worldwide. Although an infectious etiology is suspected based on the epidemiology and clinical features, a causative agent has not been identified. The majority of the morbidity and mortality associated with this condition is attributable to the development of coronary artery aneurysms. Treatment during the acute phase with intravenous immunoglobulin and acetylsalicylic acid results in significant reductions in coronary complications. The long-term management of patients with persistent coronary abnormalities is less well-defined. This article reviews the epidemiology, possible etiologies, and management of Kawasaki disease.

Increased Arterial Stiffness in Children with a Parental History of Hypertension

Abstract: The vascular dynamics of children with a parental history of hypertension has not been defined. The purpose of the current study was to determine whether or not these children have different arterial stiffness compared to the offspring of normotensive parents. One hundred healthy, nonobese subjects (ages 10–21 years) were divided into two groups of 50. Group A included the offspring of hypertensive patients and group B the offspring of normotensive parents. The variables studied were body surface area, blood pressure, and systolic and diastolic diameters of the aortic and carotid arteries as well as maximum velocity flow of these vessels. Carotid and aortic stiffness were calculated. Children and adolescents with a parental history of hypertension had higher carotid stiffness and smaller carotid diameters. These differences continued to be significant when correcting for body surface area. A higher blood pressure and a greater body surface area were also found.

Exercise testing after the Fontan operation.

Abstract: In 1971 Fontan and Baudet described an operation to separate the systemic and venous return in patients with tricuspid atresia. Subsequently, numerous modifications of the original technique have been reported and applied to patients with a variety of types of single ventricle. The eponym ‘‘Fontan’’ or ‘‘modified Fontan’’ operation is applied to the numerous operations in which systemic venous return is directed to the pulmonary arteries without passing through a ventricle and the single ventricle is used to propel pulmonary venous return to the aorta. Because of the relatively passive nature of pulmonary blood flow with this anatomic arrangement, one might expect abnormal aerobic capacity and cardiorespiratory responses to exercise.

Elevation of Cardiac Troponin I in the Acute Stage of Kawasaki Disease

Abstract: The study was performed to investigate the level of serum cardiac troponin I (cTnI), a marker specific for myocardial damage, using a chemiluminescent immunoassay in the acute febrile stage of Kawasaki disease (KD). The study population consisted of 45 KD patients before intravenous gamma-globulin (IVGG) therapy and a control group of 20 patients without KD. Among KD patients the results from measurements of the level of cTnI were positive in 18 cases (40%) and the creatine kinase (CK)-MB was positive in 11 cases (24%), but in the control group both the cTnI and CK-MB results were negative. Seven KD patients (15.6%) showed increases in both cTnI and CK-MB that were significantly correlated with each other (p < 0.05); however, CK-MB is not heart-specific. A significant increase in the level of cTnI in the acute stage of KD suggests that acute myocarditis or myocardial cell injury begins in the early phase of the disease (p < 0.05). The serologic test for cTnI can thus be a useful method for the early diagnosis of acute myocarditis and may enable early treatment with IVGG to reduce the cardiovascular abnormalities in KD patients.

Exercise testing in children with primary pulmonary hypertension.

Abstract: Cardiopulmonary exercise testing is a useful noninvasive tool to assess physiological changes associated with exercise. Developing noninvasive methods to assess the severity of cardiopulmonary disorders, as well as the response to therapeutic interventions, is useful in conditions, such as primary pulmonary hypertension, in which invasive procedures carry significant risks. The 6-minute walk test is a simple measure of exercise endurance. Exercise studies that measure both hemodynamic and ventilatory responses provide additional information regarding the interaction of the circulatory and pulmonary systems. Subtle changes in exercise capacity may suggest deterioration prior to clinical manifestations. This may lead to an earlier reevaluation, including repeat cardiac catheterization, and subsequently changes in medical and/or surgical therapy.

Cardiovascular involvement in a boy with Sweet's syndrome.

Abstract: Acute febrile neutrophilic dermatosis (Sweet's syndrome) is a rare disease in infancy. It may present in an isolated manner or be associated with diverse conditions. Only two children with postinflammatory slack skin who developed cardiovascular disease have been described to date, both of whom died from coronary artery occlusion. We report a boy with Sweet's syndrome and diffuse vascular disease involving the aorta and the supraaortic vessels, the pulmonary trunk, and the right coronary artery but without signs of coronary obstruction.

Left ventricular diastolic filling patterns associated with progressive anthracycline-induced myocardial damage: A prospective study.

Abstract: The objective of this study was to examine changes in diastolic function associated with progressive myocardial damage and their implications. We used prospective sequential Doppler echocardiographic studies of left ventricular (LV) function. The study included 125 consecutive children (median age 6.3 years) receiving anthracyclines to cumulative doses between 45 and 1150 mg/m2 (median 270 mg/m2). We measured peak early (E) and atrial (A) phase filling velocities, EA ratio, deceleration and isovolumic relaxation times (EDecT and IVRT), heart rate, and fractional shortening (SF). Results were compared serially and with individually paired control data matched for body surface area. Progressive myocardial damage was evidenced by a mean SF decrease of 1 absolute %/100 mg/m2 of anthracycline. Six patients developed cardiac failure. After 1–100 mg/m2 of anthracyclines, the EA ratio decreased (mean 1.54–1.40, p= 0.02) and IVRT became prolonged (54 vs 52 msec in controls, p= 0.03). EA ratio increased again with the next dose, usually normalizing thereafter. Twelve patients ended treatment with an EA ratio 2 (2 cardiac deaths). Diastolic abnormalities were not strongly predictive of reduced SF. Modest changes in left ventricular diastolic filling patterns occur during anthracycline treatment of childhood malignancies. Although 20% of patients have significant abnormalities of diastolic filling by the end of treatment, considerable individual variability renders the pathophysiological and clinical implications of the early changes uncertain.

The relation between right ventricular function and left ventricular morphology in hypoplastic left heart syndrome: angiographic and pathological studies.

Abstract: Cases of hypoplastic left heart syndrome (HLHS) were studied angiographically in 18 patients and pathologically in 22 patients. They were divided into three subgroups according to the morphological features of the left heart: mitral atresia with aortic atresia (MA/AA), mitral stenosis with aortic atresia (MS/AA) and mitral stenosis with severe aortic stenosis (MS/AS). Patients with MS/AA had a significantly lower right ventricular end-diastolic volume index and more hypokinesis of the right ventricular posterior wall than those with MA/AA. MS/AA not only increased the thickness of the left ventricular posterior wall and interventricular septum but also increased endocardial thickness compared with MA/AA. Myocardial histology revealed more frequent abnormal findings such as myocardial necrosis, calcification and interstitial fibrosis in the mitral stenosis groups (i.e., MS/AA and MS/AS) than in MA/AA. Right ventricular function appeared to be greatly influenced by left heart structure. The presence of larger left ventricular muscle bulk and frequent myocardial damage seen in MS/AA seems disadvantageous to right ventricular end-diastolic volume and right ventricular wall motion.

Elastin mutation and cardiac disease.

Abstract: Characterization of the molecular basis of structural cardiac disease includes elucidating the pathogenesis of certain vascular disease by demonstrating mutations of the Elastin gene as the cause of familial supravalvular aortic stenosis (SVAS) and Williams' syndrome (WS). Defining the etiology of SVAS has clinical implications in terms of prenatal and presymptomatic diagnosis and possible earlier intervention with medical therapy. This review considers the evidence relating Elastin mutations to SVAS and WS and outlines the possible mechanisms by which these mutations give rise to cardiac disease. Finally, the implications which Elastin mutation identification has on current clinical practice and future research directions are considered.

Electrophysiological follow-up of tetralogy of fallot.

Abstract: Arrhythmias and sudden death are well-recognized complications that occur late after correction of tetralogy of Fallot. This study, based on the literature and personal work, reviews the numerous investigations prompted by these complications and provides recommendations regarding follow-up. Conduction disturbances and ventricular arrhythmias are both common; although mostly asymptomatic, they are the likely cause of syncopy and sudden death. Supraventricular arrhythmias are less common but cause symptoms more frequently. Detecting patients at risk for life-threatening arrhythmias is an important task. The simple surface electrocardiogram (ECG) gives a host of information regarding patients at risk. Holter recordings, signal-averaged ECG, and invasive electrophysiological studies may all be helpful; the indications to perform these investigations are discussed and propositions are made for the follow-up of the postoperative patient. There is hope that a systematic approach along these lines, together with surgery done at an earlier age, will decrease the incidence of severe arrhythmias and sudden death in the future.

Normative Cardiovascular Responses to Exercise in Children

Abstract: The ‘‘typical’’ cardiovascular responses to dynamic exercise in normal children and adolescents are summarized. The term ‘‘normative data’’ is somewhat of a misnomer because of variability in exercise protocols, subject populations, and measurement methodology [15]. Although pediatric cardiovascular responses to exercise are in many ways similar to those in adults, differences are found in many areas. These are noted, as are the effects of gender, ethnicity, protocol, position, and training on cardiovascular responses to dynamic exercise.

Exercise Testing of the Child with Obesity

Abstract: As the prevalence of childhood obesity increases, exercise testing of obese children is likely to increase as well. This article discusses the implications of pediatric obesity for exercise testing and provides some recommendations for conducting tests and evaluating results. Studies comparing obese and nonobese children during exercise testing indicate that obese children are capable of meeting the challenges of exercise testing to nearly the same extent as their nonobese peers. Their physiologic responses, at least for the levels of obesity reported in the literature, are not sufficiently different from their nonobese counterparts to necessitate major changes in test protocols. Laboratory staff should pay special attention to fostering confidence in the obese child during the pretest routine.

Effects of gamma-globulin on the cardiac sequelae of Kawasaki disease.

Abstract: Our aim was to delineate the effect of various factors, such as sex, age, serum albumin levels, and the timing of gamma-globulin (GG) therapy, on cardiac sequelae of Kawasaki disease. The patients with Kawasaki disease who were reported at the 1995-1996 nationwide survey and received 2000 mg/kg at specified hospitals were selected as the subjects of the study. A total of 2221 patients actually received the basic dose. The relationships of the GG therapy with the cardiac sequelae, sex, age, timing of GG administration (the date of initiation and duration of the regimen following disease onset), and serum albumin levels were examined by using logistic regression analysis. The odds ratios for the cardiac sequelae in patients with Kawasaki disease were high in males (1.63), in those under the age of 1 year (1.54), and in those with a serum albumin level <3.2 g/dl (2.64). The odds ratio was low in those who received GG before day 8 of the illness (0.69) or in those for whom the administration period was for 2 days or less (0.67). To prevent cardiac sequelae of Kawasaki disease it is desirable that GG therapy be started as soon as possible and completed within 2 days.

Percutaneous transluminal angioplasty for stenosis of the aorta due to aortic arteritis in children.

Abstract: Percutaneous transluminal balloon angioplasty for stenosis of the aorta due to aortic arteritis was attempted on 45 lesions in 41 children (age range, 4–14 years; mean, 9.9±4.2 years) presenting with symptoms of hypertension, severe congestive heart failure, and lower limb claudication. Balloon dilatation was technically successful in 38 (92.7%) patients for 41 stenotic lesions (91.1%). The mean peak systolic pressure gradient (PSG) decreased from 71.7 ± 23.9 mmHg to 23.2 ± 17.5 mmHg (p 50%, and 1 for recurrent restenosis. There was marked hemodynamic and angiographic improvement in these 4 patients. Hemodynamic and angiographic restudy in 21 of the 41 patients at mean follow-up period of 6.2 ± 4.2 months (range, 3–24 months) showed restenosis in 4 (19%) patients. Restenosis was more common in patients with long-segment stenosis than those with short-segment stenosis (30% vs 9.1%). Late restudy in 8 patients, done at 3–7 years after first restudy, showed no recurrence of aortic narrowing. On clinical follow-up of 38 patients for a mean of 58.8 ± 36.0 months (range, 8–146 months) there was marked improvement in symptoms. Hypertension was cured in 11 (29%), improved in 24 (63%), and persisted in 3 (8%). Six patients with associated severe renal artery stenosis showed further improvement in hypertension after successful renal angioplasty. Severe congestive heart failure improved in 21 (95.4%) of 22 patients. Mean left ventricular ejection fraction improved from 0.32 ± 0.08 to 0.48 ± 0.10 (p < 0.001) at a mean follow-up of 28.7 ± 8.4 months in these patients. Hemodynamic restudy in 10 of these patients showed improvements in left ventricular end-diastolic pressure from a mean 37 ± 9 mmHg (range, 25–55 mmHg) to 16.4 ± 6.2 mmHg (range, 6–25 mmHg) (p < 0.001). Lower limb claudication improved in all 4 patients. Our results suggest that percutaneous transluminal balloon angioplasty in children is safe and highly effective in relieving stenosis of the aorta due to aortic arteritis, with marked clinical improvement, and should be the treatment of choice particularly for discrete stenosis.

Autonomic Changes and Heart Rate Variability in Children with Neurocardiac Syncope

Abstract: This study evaluated resting autonomic function and autonomic responses to head-up tilt-table testing in children who experienced neurocardiac syncope to determine whether predictable differences existed between these patients and normal volunteers. Neurocardiac syncope is a common cause of syncope in children. The mechanism, though related to abnormalities in autonomic function, has not been fully elucidated, particularly in pediatric patients. This study evaluated resting autonomic tone using noninvasive autonomic function tests (i.e., Valsalva, handgrip, and deep breathing) and 24-hour heart rate variability (HRV). In addition, heart rate and blood pressure were evaluated during head-up tilt examination. Values from patients who experienced neurocardiac syncope were compared to those from age-matched normal volunteers. No significant differences were noted during noninvasive testing. Some time domain HRV variables demonstrated a trend toward significant difference (p < 0.10). Tilt testing data were significantly different in sinus beat to sinus beat (RR) intervals between controls and syncope patients at 2, 5, and 10 minutes after tilting. In addition, significant differences were noted in RR interval and the standard deviation of RR interval 1 or 2 minutes prior to syncope when compared to controls at 5 and 10 minutes after tilting. Children with syncope exhibited abnormalities during tilt testing indicating an increased sympathetic or decreased parasympathetic tone, particularly prior to syncope. Some measures of HRV might constitute noninvasive parameters that correlate with the positive tilt table test.

Double-Lumen Aortic Arch by Persistence of Fifth Aortic Arch: A New Case Associated with Coarctation

Abstract: A coarctation of aorta with double-lumen aortic arch due to persistence of an embryonic fifth aortic arch was recognized in a 13-day-old girl and successfully repaired using enlargement of the aorta by side-to-side anastomosis of the fourth and fifth aortic arches.

Neurally mediated syncope in children: results of tilt testing, treatment, and long-term follow-up.

Abstract: Despite a great deal of literature concerning children with neurally mediated syncope (NMS) there is no clear standard of diagnosis or consistent approach to therapy. This report reviews our experience with tilt testing all patients who presented with syncope during a 3-year period. All patients referred for evaluation of syncope who underwent tilt testing were retrospectively reviewed. Follow-up was obtained at return visits or by telephone interview. Sixty patients were identified. The average age was 13.5 ± 3.0 years. Twenty-six patients (43%) had positive tilt tests. Follow-up was available for 56 patients. Twelve of these patients had causes other than NMS found for their symptoms. The remaining 44 patients all had histories consistent with NMS. Nineteen of these patients had positive tilt tests. All 44 patients reported either a decrease or no recurrence of syncope, and 41 patients reported a decrease or no recurrence of presyncopal symptoms. Recurrence of syncope or symptoms was not related to the results of the tilt test. Twenty-five of the 44 patients used conservative measures (extra fluids or supplemental salt) and only 3 patients were taking medications. The use of conservative measures or medications was not related to the tilt test results. Tilt testing has a high false-negative and false-positive rate and should not be used as the standard for identifying patients with NMS. The long-term follow-up of patients with NMS demonstrates that regardless of the results of the tilt test, almost all have improved or resolved symptoms with simple interventions.

Acute Inferior Cardiac Inflow Obstruction Resulting from Inadvertent Surgical Closure of a Prominent Eustachian Valve Mistaken for an Atrial Septal Defect

Abstract: A 5-month-old boy with a VACTERL syndrome underwent cardiac surgery for correction of a common arterial trunk and closure of an atrial septal defect. A prominent Eustachian valve was mistaken for the atrial septum and surgically closed. Thirty months later, after gradual shrinking of the foramen ovale with associated reduction of the right-to-left shunt, the boy presented with acute symptoms of a lower inflow obstruction, characterized by hepatomegaly and engorged abdominal vein pattern (Medusa's head). The boy was reoperated successfully after the condition had been recognized.

Secondary cardiac tumor in children.

Abstract: We describe our clinical experience of eight cases of secondary cardiac tumor. The pathology of the tumors were lymphoma (three), Wilms' tumor (two), malignant teratoma (one), neuroblastoma (one), and pleuropulmonary blastoma (one). Metastatic sites were the right atrium in Wilms' tumor and neuroblastoma, the left atrium in pleuropulmonary blastoma and malignant teratoma, and multiple sites in lymphoma. Primary masses in the mediastinum extended directly to the heart (three lymphoma, malignant teratoma, pleuropulmonary blastoma). Wilms' tumor and neuroblastoma showed cardiac metastases through the inferior vena cava. Many cases revealed vague abnormal cardiovascular findings (symptoms in six; physical signs in five). In five cases surgery was performed to relieve the possible obstruction to flow and to identify the pathology (lymphoma in three, Wilms' tumor in one, and malignant teratoma in one). Chemotherapy prior to operation resulted in the disappearance of the intracardiac masses in each case of Wilms' tumor and pleuropulmonary blastoma. All three patients with lymphoma died immediately after operation. Four died of multiple metastases or Pneumocystis pneumonia several months after operation. This study indicates that suspicion of a secondary cardiac tumor is crucial to early diagnosis. Because of the poor postoperative outcome, surgery for secondary cardiac tumors should be done cautiously only in cases with definite hemodynamic decompensation.

Cardiorespiratory Testing: Anaerobic Threshold/Respiratory Threshold

Abstract: Complete exercise testing is more than simply running on a treadmill or riding on a cycle ergometer. These simple measures may be used to evaluate endurance, peak heart rate, blood pressure, and the presence or absence of dysrhythmias during exercise. With the use of rapid gas analyzers and microcomputers, information about ventilation, oxygen supply and use, and the metabolism at the muscle level may be obtained noninvasively. The concept of the ventilatory anaerobic threshold and the transition from aerobic to anaerobic metabolism during a graded exercise test are discussed. Tests that evaluate only anaerobic performance (i.e., the Wingate test) will not be discussed.