Early left ventricular abnormality/dysfunction in obese children affected by NAFLD

BACKGROUND AND AIMS

Although it is generally accepted that non alcoholic fatty liver disease (NAFLD) is linked to increased risk of cardiovascular disease, the presence of abnormalities in cardiac function among NAFLD children is limited and controversial. Aim of the study was to detect cardiac abnormalities/dysfunction in a paediatric population of NAFLD.

METHODS AND RESULTS

Anthropometric, laboratory, cardiovascular fitness, 24 h blood pressure monitoring and Doppler echocardiography parameters were obtained in 50 untreated children (37 males; mean age 12.2 + 2.5) with biopsy-proven NAFLD. Abnormalities in both cardiac function and geometry could be identified in the whole study population: prevalence of about 35% in left ventricular hypertrophy, 14% of concentric remodelling and 16% of left atrial dilatation. Furthermore children with NAFLD (NAS score <5) showed lower cardiac alterations compared to NASH patients (NAS score >5). After adjusting for age, sex and BMI, a positive correlation was found only between LV mass and NAS score (p < 0.001).

CONCLUSION

Our results suggest that cardiac dysfunction can be detectable early in NAFLD children and this is not linked to cardiovascular and metabolic alteration, other than to liver damage. Although as a preliminary stage, we can speculate a possible direct relationship between liver and heart steatosis, already occurring during childhood.

Impaired energy expenditure despite normal cardiovascular capacity in children with type 1 diabetes

BACKGROUND

Benefit of fitness on children with type 1 diabetes mellitus (T1DM) is still debated.

AIM

To evaluate the influence of physical activity on metabolic balance and exercise tolerance in prepubertal children affected by T1DM.

METHODS

We analyzed 35 pre-/peripubertal T1DM children and 31 matched controls using an activity monitor (SenseWear Armbad) and physical activity questionnaire (PAQ) to assess energy expenditure (EE), total and active, sedentary and physical activities (h/day and Mets = metabolic equivalents). The maximal cardiopulmonary exercise test (CPET) was also performed.

RESULTS

Total physical activities and total and active EE (>3 Mets) resulted higher in controls than in T1DM patients and self-reported perception of physical and sedentary activities was altered in T1DM children as well in controls and were different from the measured data. No differences were found in CPET parameters with the exception of a higher maximal blood pressure in T1DM children. In multivariate analysis HbA1c negatively correlated with VO(2).

CONCLUSION

Prepubertal T1DM children seem to have a lower level of physical activity and EE and a probable altered feeling of physical and sedentary activities. On the other hand, T1DM children do not show any alteration of cardiovascular performance, although glycemic control (HbA1c) may play a role in cardiovascular performance.

Energy expenditure and insulin sensitivity evaluation in obese children affected by hepatosteatosis

OBJECTIVES

The aim of our study was to evaluate the physical and sedentary activities and energy expenditure (EE) in a group of children affected by non-alcoholic fatty liver disease (NAFLD), compared with normal and obese subjects, using a physical activity questionnaire (PAQ) and a SenseWear armband (SWA).

METHODS

Forty NAFLD (10 females), 41 lean (NRM; 11 females) and 30 obese (OB; 10 females), age- and pubertal stage-matched, children were included.

RESULTS

Sedentary activity (PAQ) was similar in NAFLD and NRM but less in OB, while SWA showed that NAFLD spent less time in physical activity and more in sedentary activities compared with NRM, but not with OB. Insulin sensitivity index result is related to active EE (cal kg(-1)  d(-1) ) in NAFLD, while homeostatic model assessment index result was negatively related to total EE in OB.

CONCLUSIONS

Regular physical activity must be encouraged in all obese children affected by NAFLD or not, and SWA might be a possible valid tool for evaluating actual EE.

A pilot trial on safety and efficacy of erythrocyte-mediated steroid treatment in CF patients

BACKGROUND

Chronic neutrophil inflammation of the respiratory tract tissues plays a key role in the pathogenesis and in prognosis of cystic fibrosis (CF). It is evident that an anti-inflammatory therapy represents an important step in the treatment of CF patients. Corticosteroids and ibuprofen have been proven to slow down the impairment of the pulmonary function in CF patients but their use is limited by the frequency of adverse events. A novel strategy for delivering low doses of steroids for long periods through the infusion of autologous erythrocytes loaded with dexamethasone has been recently set up. A recent study suggested the feasibility of therapy with low doses of corticosteroids delivered through engineered erythrocytes in CF patients. This study presents a further analysis of safety and efficacy of this therapy.

METHODS

The treatment group was not randomised and the assignment was based on the patient's consent. Patients entered the study if they had a forced expiratory volume in 1 second (FEV1) <70%, puberty development completed, pancreatic insufficiency, and chronic pulmonary infection requiring frequent cycles of intravenous antibiotic therapy. Patients were excluded if they underwent systemic corticosteriod therapy in the three months preceding the experimental treatment or were on therapy with non-steroidal anti inflammatory drugs (NASDs), or if they had liver CF disease, allergic bronchopulmonary aspergillosis, or positive tuberculin test. Controls were patients who followed a standard treatment, who fulfilled the enrollment criteria, and who were matched to the experimental group by gender, age, and severity of the disease.

RESULTS

Nine patients in the experimental group received the treatment once a month for a period of 24 month. Patients did not develop diabetes, cataract, or hypertension, or other typical side effects of steroid treatment during the follow up period. There was a constant improvement of FEV1 in patients undergoing the experimental treatment compared to a gradual decrease of the same parameter in the standard therapy group (P = 0.04). The average of clinic and radiological indexes did not vary. The number of infective relapses that have required antibiotic intravenous therapy was not different in the two groups, although the average of these episodes was slightly higher in the experimental therapy group.

CONCLUSION

Intraerythrocyte corticosteroid treatment may stabilize the respiratory function in CF patients but is often considered too invasive by patients. The results obtained by our study may help planning an experimental, controlled, randomised study. A sample size of 150 patients per group would be sufficient for demonstrating such a difference with a 95% confidence interval and a power of 90%.

Cardiovascular hemodynamics: relationships with insulin resistance in obese children

We investigated blood pressure (BP), cardiac output (CO), and systemic vascular resistance (SVR) and their relationships with insulin and glucose blood levels in a group of 24 obese children (mean age, 11.9 +/- 2.1 years; 19 males). The data were compared to those obtained from a group of 19 healthy controls of the same age (12.4 +/- 2.1 years; p = NS; 13 males). BP at rest was measured and all subjects underwent an exercise testing on the treadmill (Bruce Prot.), time of exercise, maximal heart rate, maximum systolic blood pressure, CO, and SVR at rest and at peak exercise were considered. Only in the OC group were an oral glucose tolerance test were performed to calculate insulin sensitivity index (ISI) and echocardiography performed to determine the left ventricular mass (LVM). The relationships between cardiovascular and metabolic parameters were investigated. Student's t-test and linear regression analysis were used when appropriate. OC had a significant reduction in TE and higher BP, and linear regression analysis showed significant correlations between BP, ISI, and LVM. We speculate that OC need a regular cardiovascular and metabolic screening to prevent the development of early cardiovascular damage.

Cardiopulmonary performances in young children and adolescents born with large abdominal wall defects

BACKGROUND/PURPOSE

As long as the survival rate of patients with abdominal wall defects (AWD) increases, information about long-term follow-up is becoming necessary. Even though quality of life in these patients, in absence of associated anomalies, appears to be unaffected, respiratory impairment soon after birth has been documented; therefore, participation in sports rarely is addressed.

METHODS

Eighteen patients, ranging in age from 7 to 18 years, operated on at birth for large abdominal wall defects (> 4 cm for gastroschisis; >6 cm for omphalocele) were asked to come for a stress test on a treadmill, with measurements of time of exercise (TE), maximal oxygen consumption (VO2 max) and continuous recording of vital parameters. Respiratory function also was assessed by Forced Vital Capacity (FVC).

RESULTS

Ergometric data were compared with those of a normal pediatric population. All patients were able to perform the stress test with no cardiovascular abnormalities detected at rest or on exertion. Maximum heart rate was reached after a significantly shorter TE, and VO2 max was significantly reduced when comparing normal subjects with AWD subjects and AWD subjects in sports with those sedentary. FVC was only slightly reduced in AWD patients without reaching statistical significance.

CONCLUSIONS

These findings indicate that patients operated on for AWD at birth exhibit a normal cardiorespiratory function; decreased TE and VO2 max are likely to reflect a lack of physical activity with a lower degree of fitness. Therefore, no limitations to motor performances should exist for these patients. Well-being may be greatly improved by regular exercise.

Does chronic pacing affect exercise capacity after Mustard operation for transposition of the great arteries?

Late survival after Mustard repair of transposition of the great arteries is generally good but is often characterized by progressive deterioration of ventricular function and by late postsurgical arrhythmias, thus imposing the need for permanent pacing. To evaluate how chronic pacing affects long-term exercise capacity, we compared two groups of these patients: group 1, comprising 12 patients, aged 9.0 +/- 2.6 years, without pacemaker; and group 2, comprising 18 patients, aged 9.3 +/- 2.0 years, with pacemaker. Patient evaluation included history, physical examination electrocardiograph, Holter monitoring, and echocardiography. Pacing modes were as follows: AAI (6 patients), AAIR (9 patients), VVI (2 patients), and VVIR (1 patient). At exercise test we evaluated exercise tolerance, maximum heart rate, blood pressure, oxygen consumption, and cardiac output at rest and at peak exercise. The two groups were comparable for all variables examinated. All pacemakers showed normal function. During the exercise, 11 of 12 patients in group 1 showed sinus rhythm, and in group 2, 11 patients showed sinus rhythm, 5 junctional rhythm, and 2 continuous pacing. There were no significant differences between groups. Chronically paced Mustard patients but with restoration of spontaneous rhythm during the exercise test do not show reduced exercise tolerance in comparison with nonpaced Mustard patients.

Cardiorespiratory functional assessment after pediatric heart transplantation

Limited data are available on the exercise capacity of young heart transplant recipients. The aim of this study was therefore to assess cardiorespiratory responses to exercise in this group of patients. Fourteen consecutive heart transplant recipients (six girls and eight boys, age-range 5-15 yr) and 14 healthy matched controls underwent a Bruce treadmill test to determine: duration of test; resting and maximum heart rates; maximum systolic blood pressure; peak oxygen consumption (VO2 peak); and cardiac output. Duration of test and heart rate increase were then compared with: time since transplantation, rejections per year, and immunosuppressive drugs received. The recipients also underwent the following lung function tests: forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). When compared with healthy controls, transplant recipients had tachycardia at rest (126 +/- 3.7 beats/min; p < 0.001); significantly reduced tolerance (9.3 +/- 0.4 min; p < 0.001), a maximum heart rate of 169 +/- 5.4 beats/min (p < 0.05); a cardiac output of 5.65 +/- 0.6 L/min (p < 0.05); and a lower heart-rate increase from rest to peak exercise (p < 0.001) but a similar VO2 peak. The heart-rate increase correlated significantly with time post-transplant (r = 0.55; p < 0.05), number of rejection episodes per year (r = - 0.63; p < 0.05), and number of immunosuppressive drugs (r = - 0.60; p < 0.05). The recipients had normal FVC and FEV1 values. After surgery, few heart transplant recipients undertake physical activity, possibly owing to over-protective parents and teachers and to a lack of suitable supervised facilities. The authors stress the importance of a cardiorespiratory functional evaluation for assessment of health status and to encourage recipients, if possible, to undertake regular physical activity.

Exercise testing and 24-hour ambulatory blood pressure monitoring in children with Williams syndrome

The aim of the study was to assess workload capacity and blood pressure (BP) response to treadmill exercise and 24-hour BP monitoring in children with Williams syndrome. Seventeen children were examined (8 males and 9 females) whose mean age was 13.8 +/- 3.6 years. Six patients were on antihypertensive therapy. Each patient underwent clinical examination and measurement of BP at rest, during exercise, and during 24-hour monitoring. Two-dimensional echocardiogram and echo-Doppler of renal arteries were performed. The test was stopped for muscular fatigue or reduced cooperation. The patients, when compared to a population of healthy children, had reduced total time of exercise (7.3 +/- 1.9 vs 14.3 +/- 2.6 min, p < 0.001) and, at the same workload, increased heart rate (167 +/- 19 vs 145 +/- 16 beats/min, p < 0.001) and increased maximum systolic BP (146 +/- 27 vs 128 +/- 12 mmHg, p = 0.01). Ambulatory blood pressure measurement values showed higher systolic blood pressure both during daytime and nighttime. Our study confirms that children and adolescents with Williams syndrome are at high risk for hypertension, probably related to the alterations of large arteries. The data relating to the synthesis of elastin may have a direct relationship to the compliance of the arterial system, leading to hypertension.

Exercise and sports participation after surgery for congenital heart disease: the European perspective

The success of surgery for congenital heart disease which has been performed since many years has created a population of patients who require careful follow-up in order to determine their clinical progress and to establish the type and intensity of physical activity which they can safely perform. The authors illustrate the opinion of the European Community regarding children, sport and organizational aspects and also problems concerning the management of pediatric cardiac patients in Europe and Italy. Cardiological and surgical aspects are considered together with the practice of physical activity, with emphasis upon the differences between the various countries. Particular attention is paid to the Italian legislation regarding the certification to participate in competitive or non-competitive sport in such a population of patients. Great importance is given to pediatric cardiac rehabilitation programs which aim at improving the aerobic fitness of patients operated upon for complex congenital heart disease and at illustrating their own cardiovascular limitations so that they can perform physical exercise with the utmost safety.

Neuroregulation of growth hormone during exercise in children

Physical exercise is an important physiological stimulus to growth hormone (GH) release in man. Many neurotransmitters are involved in GH regulation. We studied the effect of the cholinergic pathway on GH secretion induced by physical exercise. Particularly, we studied the effect of a cholinergic muscarinic agonist on GH-induced physical exercise, both in children and adults. Moreover, we investigated the refractoriness of GH secretion after a second physical exercise stimulus. Three different protocols were performed: 1) GH response to physical exercise in children and adults; 2) effect of pyridostigmine on exercise-induced GH secretion in children and adults; 3) GH response to two consecutive exercises in children and adults. Our data show that in children GH peak after physical exercise is higher than in adults. Pyridostigmine enhances GH release in children and in adults. Exercise stimulus was able to release GH in the second test only in children, while the refractory phase did not permit a new GH release in adults. The shift to a modality of neural control of GH secretion peculiar of adults is likely due to neuroregulatory mechanisms which may be partly dependent on long-term variation in hormonal milieu.

Ambulatory blood pressure monitoring in children with aortic coarctation and kidney transplantation

BACKGROUND

Ambulatory blood pressure monitoring (ABPM) has been found to be of significant importance in clinical practice because numerous blood pressure (BP) measurements may be made throughout the 24-hour period.

OBJECTIVE

To assess the clinical utility of ABPM in children with secondary hypertension.

METHODS

We studied 37 patients (21 boys and 16 girls), with a mean age of 16.4 +/- 4.1 years, after kidney transplantation and 38 patients (27 boys and 11 girls), with a mean age of 10.2 +/- 2.1 years, after surgical correction of aortic coarctation. Data, expressed as mean +/- SD, were analyzed after dividing the patients into 4 groups. Group A consisted of 25 patients receiving antihypertensive therapy; group B included 12 patients not receiving antihypertensive therapy. Group C included 25 patients operated on before 3 years of age (8 +/- 7 months of age); group D included 13 patients operated on after 3 years of age (74 +/- 29 months of age).

RESULTS

In groups A and B, casual BP measurement showed that 16 of 37 patients (43%) were hypertensive; 24-hour ABPM detected a larger number of patients who were hypertensive (23 of 37, 62%); there were 18 in group A and 5 in group B. In groups C and D, casual BP measurement identified 6 of 38 (15%) patients as hypertensive, whereas 24-hour ABPM again identified a higher number (13 of 38, 34%).

CONCLUSIONS

Our findings confirm that 24-hour ABPM is more sensitive than casual BP in detecting abnormal BP in patients at high risk for secondary hypertension.

Clinical and cardiorespiratory assessment in children with Down syndrome without congenital heart disease

OBJECTIVE

To assess the clinical and functional status of a young Down syndrome (DS) population without congenital heart disease.

DESIGN

Prospective study of children with DS and control subjects.

SETTING

Bambino Gesù Children's Hospital, Rome, Italy.

PARTICIPANTS AND METHODS

Forty-two children with DS (mean +/- SD age, 9.8 +/- 3.6 years) underwent genetic, clinical, neuropsychological (IQ), and cardiorespiratory evaluation. Cardiorespiratory fitness was assessed with a treadmill test and a lung function test to determine forced vital capacity, first-second forced expiratory volume, and peak expiratory flow. Data were expressed as a percentage of the predicted values for control children. To assess cooperation during exercise testing, we devised a compliance scale assigning a score according to the subjects' ability to understand instructions, ability to walk and run as required, and need for vocal encouragement.

RESULTS

Eighteen (43%) of 42 children with DS were obese, 10 (24%) were short, and 17 (40%) had microcephaly. On the Leiter International Performance Scale, 2 of 35 subjects had a normal IQ score (80-120); all others had low IQ scores (79 to <40). Five subjects did not undergo cardiorespiratory assessment. Eighteen of 37 subjects completed lung function tests: the results for 10 were unremarkable, and results from 8 revealed reduced forced vital capacity because of poor compliance. The subjects tested had low exercise tolerance (mean +/- SD tolerance percentage, 61% +/- 12%), mild tachycardia (maximal heart rate, 91% +/- 4%), and a mild hypertensive response (maximal blood pressure, 89% +/- 8%). Compliance scores correlated significantly with exercise time and age but not with IQ.

CONCLUSIONS

Clinical and cardiorespiratory assessment is feasible in subjects with DS without congenital heart disease and should be useful in gauging their fitness level for safe physical activity.

Left ventricular hypertrophy, treadmill tests, and 24-hour blood pressure in pediatric transplant patients

BACKGROUND

Hypertension and left ventricular hypertrophy (LVH) are possible complications in pediatric patients after renal transplantation.

METHODS

We performed left ventricular echocardiography, 24-hour ambulatory blood pressure monitoring (24-hr ABPM), and treadmill tests in 28 pediatric renal transplant patients (mean age 16.1 +/- 3.7; time since transplantation 36 +/- 23 months). Left ventricular mass (LVM) was indexed for height 2.7.

RESULTS

LVH was found in 82% of the patients. Seven of these patients were normotensive by 24-hour ABPM, but five patients showed a hypertensive systolic BP response during the treadmill test. LVM/height 2.7 correlated significantly with the mean 24-hour systolic BP (P = 0.002) and with the maximal exercise systolic BP (P = 0.002).

CONCLUSION

LVH is frequent in pediatric renal transplant patients. More information is needed with respect to the risk for LVH, including data from 24-hour ABPM and treadmill testing.

Exercise tolerance and blood pressure response to exercise testing in children and adolescents after renal transplantation

The aim of the study was to assess exercise tolerance and blood pressure (BP) response to treadmill exercise in children after renal transplantation. Forty-five children were selected (29 males and 16 females) whose mean age was 14.3 +/- 4.2 years. All children had Hb >/= 10 g/dl and creatinine clearance >/=40 ml/min/1.73 m2. They were at least 6 months posttransplantation and were on triple immunosuppressive therapy. Twenty-seven were also on various antihypertensive medications. Each underwent clinical examination and measurement of BP, both at rest and during exercise testing on treadmill. The test was stopped on muscular fatigue or exhaustion. The patients were divided into two groups: those off (A) or on (B) antihypertensive therapy. When compared to a population of healthy children the patients had reduced exercise tolerance (10.1 +/- 2.1 vs 15.1 +/- 1.7 min, p < 0.001) (67 +/- 16%), increased heart rate (174 +/- 19 vs 161 +/- 19 beats/min, p < 0.001) (109 +/- 15%), and increased maximum systolic BP (150 +/- 26 vs 134 +/- 13 mmHg, p < 0. 001) (113 +/- 19%) at comparable workloads. Within the two patient groups, significant differences were observed during exercise testing for maximum heart rate, which was lower in group B (p = 0.03), and maximum systolic BP, which was higher in group A (p = 0.04). Our study confirms that children and adolescents on immunosuppressive therapy after renal transplantation have a hypertensive response during exercise, probably related to medication-induced peripheral vascular tone.

Hypertension in young patients after renal transplantation: ambulatory blood pressure monitoring versus casual blood pressure

The results of ambulatory blood pressure monitoring (ABPM) in children after kidney transplant were analyzed to ascertain any alteration in circadian BP profile, degree of hypertension, and efficacy of therapy. The data were also compared with casual BP data and left ventricular mass index (LVMI). We have examined 30 patients (17 male, 13 female), mean age 16.1+/-3.6 years after kidney transplant. All patients were receiving triple immune-suppressive therapy and 20 of them were also taking antihypertensive therapy. They underwent clinical examination with measurement of BP at rest, echocardiogram mono-2D, and ABPM. The following ABPM parameters were recorded: systolic (S) and diastolic (D) BP at rest; mean 24-h SBP and DBP; mean daytime SBP and DBP; mean nighttime SBP and DBP; nocturnal fall in SBP and DBP; and mean daytime and nighttime heart rate (HR). The patients were divided in two groups. Group A consisted of 20 patients taking antihypertensive treatment; group B consisted of 10 patients not taking antihypertensive treatment. Casual and ABPM data for the two groups were compared using the Student t test for unpaired data. Blood pressure at rest and LVMI were not statistically different between the two patient groups. The ABPM data showed statistical differences between the two groups for mean 24-h SBP and DBP, daytime and nighttime SBP, nighttime DBP, fall in nocturnal DBP, and nighttime HR. Mean 24-h SBP and DBP, mean daytime SBP and DBP, and mean nighttime SBP and DBP were significantly correlated to LVMI (respectively, P = .009, P = .005, P = .008, P = .007, P = .05, and P = .01). Twenty-four-hour ABPM was more useful in the diagnosis and management of hypertension than was casual BP at rest.

Exercise tolerance and behavior of blood pressure in children and adolescents after renal transplant

OBJECTIVE

The purpose of the study was to evaluate the exercise tolerance and the behaviour of blood pressure during a maximal exercise testing on treadmill for a group of patients with renal transplant carried out at least 6 months earlier. EXPERIMENTAL DESIGN, SETTING AND PATIENTS: In a retrospective study, nineteen patients were examined in our laboratory: 13 boys and 6 girls, mean age 15.8 years (range 10.5-22).

INTERVENTIONS

All patients were given a clinical examination, an ECG at rest, a maximal exercise testing on treadmill (Bruce protocol), a mono-2D echo, a lung function test and 24-hour Holter monitoring. The results of the exercise test were compared with those of two control groups of same age and body surface area.

RESULTS

The clinical examination of their cardiovascular apparatus gave normal results. The echo revealed anatomical and heart function anomalies related to the original disease. Exercise testing on treadmill showed a reduction in exercise tolerance (p < 0.001) and the maximal heart rate showed a statistically significant difference (p < 0.001) in comparison to control groups. Maximal systolic blood pressure was higher than in patients with same body surface area (p < 0.001) and higher than in peers (p = 0.133).

CONCLUSIONS

In view of this hypertensive response, strenuous physical activity should be undertaken with caution and indeed submaximal aerobic activity is more suitable for this population of patients.

Reciprocating supraventricular tachycardia in children: low rate at rest as a major factor related to propensity to syncope during exercise

Reciprocating supraventricular tachycardia may have several clinical presentations, with symptoms often more severe during exercise or emotional stress. This study shows by using transesophageal atrial pacing, the factors related to syncope during exercise. Between May 1989 and June 1994, transesophageal atrial pacing was performed at rest and during exercise in 75 children aged > 6 years with suspected or documented episodes of paroxysmal supraventricular tachycardia. Reciprocating supraventricular tachycardia could be induced both at rest and during exercise in 22 patients (8 girls, 14 boys; mean age 10.6 +/- 2.7 years, range 7 to 15 years) with ventriculoatrial interval < 70 msec in 11 patients and > 70 msec in 11. At rest, all patients had palpitations caused by the induction of tachycardia. After conversion to sinus rhythm, when tachycardia was induced during exercise, symptoms did not change in 14 patients (group A), whereas symptoms worsened (presyncope) in eight (group B). The statistical analysis showed a significant difference of mean reciprocating supraventricular tachycardia rate at rest between the two groups (group A, 211 +/- 23 beats/min; group B, 173 +/- 33 beats/min; p = 0.0057) and reciprocating supraventricular tachycardia rate variation from rest to exercise (group A, 62 +/- 18 beats/min; group B, 105 +/- 24 beats/min; p = 0.0001). These data suggest that children with low tachycardia rate during normal activities may have syncope more frequently, independently of the tachycardia rate during exercise or emotional stress.

Maximal oxygen consumption and stress performance in children operated on for congenital diaphragmatic hernia

The long-term follow-up of patients operated on for congenital diaphragmatic hernia (CDH) at birth has been extensively evaluated, both clinically and with respect to respiratory function. However, little is known about the sports practice and stress performance of these subjects. Fifteen of 107 patients operated on for CDH underwent exercise stress testing with a stepwise increase in workload. A questionnaire was provided, which requested information on sports practice and lifestyle. Maximal oxygen consumption [Vo2 max] was measured along with dynamic lung volumes. Clinical examination included a whole-body assessment (height, weight, skinfolds) and vital parameters (heart rate and blood pressure). Fifteen healthy children who practiced regular physical activity (2 to 4 hours/week) served as controls. All the CDH patients experienced a good lifestyle, but only 8 of them were participating in sports. Exercise duration and Vo2 max were significantly lower for the CDH patients, and were lowest for the sedentary patients. Therefore, the reduced Vo2 max of these otherwise healthy children most likely represents a lower degree of physical fitness rather than decreased respiratory function. Fitness is an expression of well-being; thus, there is evidence that these patients could safely participate in competitive motor activities.

[Functional evaluation by treadmill in children and adolescent following correction of Tetralogy of Fallot]

AIM OF THE STUDY

The Authors have examined 22 children (16m and 6f), mean age 9.64 +/- 2.63 years, range 5-15, after total correction for Tetralogy of Fallot, to evaluate the response of their cardiovascular apparatus during an exercise testing on treadmill (Bruce protocol).

METHODS

Parameters examined: exercise duration, maximal heart rate (HR), maximal systolic blood pressure (max BP), non invasive cardiac output at rest and at the peak of exercise (CO), arterial oxygen saturation; lung function test at rest, echocardiogram and 24 hours Holter monitoring.

CONTROL GROUP

22 healthy peers, same gender, height and weight, not practising competitive sports.

RESULTS

The exercise duration was significantly lower in the first group (77.8 +/- 11.8%; 86.5 +/- 8.2%; P = 0.006). Also max HR and max BP were significantly lower (max HR: 162 +/- 12 b/m'; 187 +/- 8 b/m'; P = 0.000), (max BP: 119 +/- 9 mm Hg; 126 +/- 12 mm Hg; P = 0.042). There were no differences for CO at rest (3.70 +/- 1.09 l/m'; 3.95 +/- 1.07 l/m'). In the first group, CO at peak of exercise was lower but not significantly (6.51 +/- 2.56 l/m'; 7.95 +/- 2.77 l/m'; NS).

CONCLUSIONS

These results make more complete the not invasive functional evaluation for a better follow-up of these patients and a better choice for their physical activity.

Abnormal hypertensive response during exercise test in normotensive transplanted children and adolescents

We investigated the cardiovascular and respiratory conditions, at rest and in response to stress testing, in 10 children and adolescents with successful renal transplantation, to release certifications for participation in sports. Our patients were aged more than 6 years, transplanted 6 months or more before the study, with creatinine clearance > 40 ml/min/1.73 m2, without hypertension at rest. All but 1 were on cyclosporine A, prednisone and azathioprine. Two control study groups with the same chronological age and body surface area were paired with our patients. They underwent a graded exercise tread-mill test, during which maximal blood pressure and heart rate were recorded. Resting electrocardiogram, dynamic 24-hour electrocardiogram Holter monitoring and mono- and bidimensional echocardiograms were obtained before the test. Spirometry was performed to study lung flow and volume. A questionnaire collected information about physical activity patterns. Four categories, according to practice, frequency and duration of exercise, were identified: nonactive, starters, experienced and very experienced. Most children and adolescents were sedentary or mildly interested in sports and during treadmill test we observed reduced exercise capacity and systolic hypertensive response to increasing exercise testing.

Physical fitness testing in children operated on for tracheoesophageal fistula

The maximal physical activity capacity of children operated on for tracheoesophageal fistula (TEF) has not been clearly defined. Eight patients (average age, 12 years) successfully operated on for TEF at birth underwent maximal exercise stress testing on a treadmill, according to the Bruce protocol, to test physical work capacity. Heart rate (HR), oxygen consumption (VO2), and pulmonary ventilation (VE) were measured by a portable lightweight telemetric device. Nine healthy children served as controls. Exercise duration was significantly lower for TEF subjects than for controls (11.6 +/- 1.7 minutes v 15.1 +/- 2.3 minutes; P < .01). Mean HR at rest and during exercise did not differ between the groups. All children reached the maximum HR according to their age; however, for the majority of TEF patients, this occurred at an earlier stage than in the controls. No differences were seen in mean VO2 at rest and on exertion between TEF and control children. However, maximal VO2, as measured at the end of exercise, was significantly different when normalized per kilogram of body weight (VO2/kg = 52.3 +/- 5.8 v 33.3 +/- 6.6; P < .005). The physical rehabilitation of TEF children usually takes into account only respiratory and nutritional factors. However, complete assessment of their cardiac and respiratory function, at rest and on exertion, also should be performed, because this may show that some patients have reduced motor performance; evidence is now accumulating that these children can safely participate in the same physical activities of their healthy peers.

[Transesophageal atrial stimulation in the oral treatment of supraventricular reciprocal paroxysmal tachycardia in infants]

INTRODUCTION

The aim of the study was the evaluation of the usefulness of transesophageal atrial pacing in predicting chronic oral treatment efficacy of symptomatic reciprocating supraventricular tachycardia in infants and in avoiding the risk of very dangerous recurrences at home.

METHODS

We studied 13 infants (11 males, 2 females, mean age 43 +/- 31 days) with symptomatic reciprocating supraventricular tachycardia and no structural heart disease. All patients had chronic oral therapy, using the drug effective in acute i.v. somministration. Each patient was discharged when supraventricular tachycardia was not inducible with transesophageal atrial pacing after 5 half-lives of the drug used in chronic oral treatment. All patients, every 6 months, were retested with transesophageal atrial pacing alternatively during chronic oral therapy and after complete wash out. Oral therapy was stopped in each patient when supraventricular tachycardia was not inducible after the wash out.

RESULTS

The number of oral treatments tested for each patient were 2 +/- 1 (range 1-5). The number of transesophageal studies performed for each patient were 4 +/- 2 (range 3-7). No patient had symptomatic episodes of supraventricular tachycardia or needed to change therapy during the follow-up. The oral treatment was stopped after the twelfth month of life in 8 patients and after the twenty-fourth in 2 others without recurrences.

CONCLUSION

Transesophageal atrial pacing seems to be useful in predicting accurately and rapidly the oral treatment efficacy of supraventricular tachycardia in infants. Our protocol seems to be effective to avoid dangerous recurrences of tachycardia and to decide when we can stop therapy without risk.

Efficacy and safety of ventricular rate responsive pacing in children with complete atrioventricular block

Single chamber rate responsive pacing offers many potential advantages over the more complex dual chamber atrial tracking pacing mode in children, and the preservation of atrioventricular synchrony could be unnecessary in selected groups of pediatric patients. Twenty-two pediatric patients (age range 9 months to 12 years; mean 6.5 years) had implantation of ventricular rate responsive (VVIR) pacemakers over a 2-year period. All patients had chronic third-degree atrioventricular block, and a normal ventricular function at rest. During the follow-up each patient underwent a 24-hour Holter monitoring, and ten performed a graded treadmill test in both ventricular fixed rate (VVI) and rate responsive (VVIR) pacing mode. Paced ventricular rates were found to be normal for age in all 22 patients; maximum rate did not reach the higher programmed rate during daily activities in any patient. Comparing the mean paced ventricular rate to the mean rates of blocked P waves, six patients showed a difference of more than 20 beats/min, which induced the pacemaker parameters to be reprogrammed. In all patients a significant correlation was found between variations of paced ventricular rate and variations of spontaneous blocked atrial rhythm (P < 0.05); this correlation persisted in the subsequent Holter controls in the ten patients with longer follow-up. Exercise tolerance resulted normal in the ten patients who performed a treadmill test either in VVIR or VVI mode, with increased maximal heart rates and maximal systolic blood pressure in VVIR mode (P < 0.0013). Rate responsive ventricular pacemakers seem to adequately respond to the physiological needs of daily life of this selected group of children requiring permanent pacing.

[Treatment of parapneumonic empyema in children]

A 31 case series of pleuropneumonia is presented, in a 7 year period. All patients were treated following same standards consisting of a pleural catheter insertion. Results support conservative treatment: short hospitalization and absence of psychological or physical traumas was achieved. Follow up is very good for all patients and none had invalidating consequences.

Early identification of patients at risk for sinus node dysfunction after Mustard operation

We studied 60 patients who had survived the Mustard procedure for transposition of the great arteries, performed between the ages of 2 days and 24 months (mean 4.51 +/- 3.79). All patients were given a postoperative 24-hour dynamic electrocardiogram at 15 days, 1 year and 3 years and then every 2 years. Those who were found to have sinus node dysfunction during follow-up, were given a dynamic electrocardiogram every 3-6 months. The average follow-up period was 38.7 +/- 19.8 months, median 36. Sinus node dysfunction was detected during follow-up in 20 patients (33.3% of the total), 8 of whom had had a pacemaker inserted. Risk factors for late development of sinus node dysfunction were found to include prolonged cross-clamping of the aorta during surgery (P = 0.003), especially over 50 minutes (relative risk 3.5:1), and the presence of even transient sinus node dysfunction after surgery (P = 0.006). These observations suggest, first, that sinus node dysfunction may develop after the Mustard operation as a combined effect of extensive atrial surgery and a long period of myocardial ischemia and, second, that the presence of the disease immediately after the operation sometimes indicates that it will recur or persist during follow-up.

[The life style and physical activity of the child operated on for congenital cardiopathy]

The parents of 151 children operated on for congenital heart disease have answered some questions about the scholastic, extrascholastic and physical activity of their children. Approximately 94% of the children are at the correct school level for their age. Extrascholastic activities of the city children is the same as children living in the country. During their free time 22% of the child population engages in physical activity, whereas 78% of the child population engages in physical activity at school. Among the parents, 61% think the activity of their children is normal, and 27% think it is too active. Our results demonstrate that the children operated on for congenital heart disease have a normal life during scholastic and free time, whereas, the introduction of these children to sport activities is anomalous and insufficient.

Rehabilitation of children after total correction of tetralogy of Fallot

Nine children who had undergone total correction of tetralogy of Fallot were studied with the purpose of observing the physical changes that might be produced by a period of rehabilitation in hospital and comparing these results with those of a control group having the same pathology but which had not followed a protocol for physical activity. Precise criteria were used in the selection of the patients. Careful clinical examinations and exercise tests were conducted before and after the programme, in particular maximal stress testing on the bicycle ergometer and submaximal exercise on the treadmill. The sessions were held three times weekly in a gymnasium over three months, gradually increasing the duration of each session to a maximum of one hour. During the session, heart rate was monitored with a Sport-tester 3000 so as not to exceed 60%, then 70%, of the maximal heart rate recorded during the stress test. Testing at the end of the programme demonstrated an improvement in tolerance under maximal stress in 7 of the 9 patients. As for submaximal performance, 8 out of 9 children covered a greater distance using the same parameters as for initial testing. At the end of the programme, the children all showed increased independence and initiative and more self-confidence in establishing social relations. The programme has proven to be a comprehensive method for safely improving physical fitness in these patients and represents an important starting point for a better future.

[Cycloergometric exercise test in normal children: comparison of an Italian and a North American population]

The need for a more complete protocol for bicycle ergometer exercise testing in children in our country, induced the Authors to apply the F.W. James protocol to healthy Italian children and then compare the results with a study on a similar american sample population. A total of 102 children, 67 males and 35 females, age range 4.4 - 17 years (mean 10.3 yrs), were examined following the F.W. James protocol. The Authors report the anthropometric and ergometric data obtained, the comparison with James' results and the linear correlation coefficients. Normal reference data were obtained. There were no significant differences between the results obtained from the Italian and American groups, and the correlation coefficients were satisfactory. The results will enable us to benefit from a simple and complete protocol which can be applied to healthy and sick children alike in our country.

[Diagnostic usefulness of Holter monitoring in pediatric fainting and syncope]

The aim of the study was to assess the diagnostic efficacy of ambulatory electrocardiographic monitoring in children with a previous history of fainting and/or syncope. Sixty-one children, from 2 months to 17 years of age, all at the time undergoing different physical examinations because of previous syncopal episodes were examined. All the children had a normal electrocardiogram at rest and all underwent 24 hour electrocardiographic monitoring (Holter). The ECG was normal in 48 patients. Eight children had several dysrhythmias, classified as "borderline" and five children showed a clearly pathological trend. These results are even more significant considering that standard electrocardiogram results are negative. These data underline the diagnostic importance of the dynamic electrocardiogram particularly in cases of very frequently repeated symptoms.

[Monitoring cardiac rhythm after the Mustard intervention for transposition of the great arteries]

Before Mustard's operation 27 children, from 2 days to 11 months old, with simple or complex transposition of the great vessels, underwent an electrocardiogram at rest. After operation, all the children underwent a standard electrocardiogram and 24 hours continuous Holter monitoring. Successive electrocardiograms at rest were recorded in all patients, and eleven children were successfully examined by dynamic electrocardiogram. The electrocardiogram at rest showed a sinusal rhythm in 66.7 of the patients; during the follow-up, in 33.3% non sinusal rhythm was recorded. The continuous 24 hours dynamic electrocardiogram, immediately after surgery, revealed 25.9% of the patients with non-sinusal rhythm. After 7 months, the Holter monitoring showed, in one case, a severe sinus node disfunction. Our data and those of the literature confirm the importance to follow these patients during a long period of time, because it was found that, even bedately, can develop serious arrhythmias.