Physical activity, fitness, and dyspnea perception in children with congenital diaphragmatic hernia.

We assessed whether physical activity could influence the performance and perception of dyspnea in children who were operated on for high risk congenital diaphragmatic hernia (CDH). We hypothesized that CDH children with normal activity would have better lung function and exercise performance level when compared to sedentary CDH subjects. We studied 18 children (11 males and 7 females, mean age 6.6 ± 2.6 years) who were surgically corrected. All children underwent physical examination, ECG at rest, and a maximal exercise stress test on a treadmill to measure the duration of exercise, maximal heart rate and blood pressure, maximal oxygen uptake (VO(2) max and VO(2) ml/kg/min). Lung function testing to measure forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV(1) ), and peak expiratory flow (PEF) was also performed. Following the stress test, the Dalhousie dyspnea and effort scale was shown to children as a pictorial panel with three groups of increasing (from 1 to 7) levels of effort perception, throat discomfort, and chest dyspnea. Children were divided into group A (sedentary) and group B (regular physical participation). There was no difference in CDH severity between the two groups. Group A had a statistically significant lower duration of exercise (P < 0.01), maximal oxygen consumption (VO(2) max P < 0.0001), VO(2) ml/kg/min (P < 0.001), higher throat closing feeling (P < 0.004), chest dyspnea (P < 0.001), and effort perception (P < 0.04) compared to group B. No differences were found in lung function tests. In conclusion, our data may suggest that children with a history of CDH who are active maintain a higher level of performance with less perception of dyspnea and effort.

Usefulness of ambulatory blood pressure monitoring and head-up tilt test in the evaluation of paediatric syncope.

OBJECTIVES: The aim of this study was to investigate the usefulness of ambulatory blood pressure monitoring versus head-up tilt test in the evaluation of children with a history of syncope. STUDY DESIGN: We considered 146 consecutive children with more than one episode of syncope. All patients had a normal electrocardiogram at rest and were otherwise considered to be healthy. Forty-six patients,19 male, with a mean age of 13.6 plus or minus 5.6 years, were studied with a head-up tilt test and 100 patients, 41 male with a mean age of 9.4 plus or minus 5.6 years, were studied with ambulatory blood pressure monitoring. Twelve patients underwent both procedures. Hypotension during ambulatory blood pressure monitoring was defined when mean blood pressure values were lower than the 50th centile and the head-up tilt test was positive when syncope occurred. All patients were followed for 10 plus or minus 2 months. RESULTS: Ambulatory blood pressure monitoring showed postural hypotension in 91% children, while head-up tilt test was positive for 54%. In the group of children having both tests, two of them were negative for both, 10 of 12 children had a positive ambulatory blood pressure monitoring while only five of 10 children had a positive response to head-up tilt test. CONCLUSIONS: When a child with a normal resting electrocardiogram is referred with a typical history of syncope, the use of ambulatory blood pressure monitoring as a non-invasive first step for diagnosis of postural hypotension may be more sensitive than the head-up tilt test. Behavioural adjustments resolved the continued syncope in most cases. If episodes persist then the head-up tilt test is indicated.

Mid-term results, and therapeutic management, for patients suffering hypertension after surgical repair of aortic coarctation.

We designed our study to investigate the efficacy of a new therapeutic approach to late onset hypertension in patients after surgical repair of aortic coarctation. Several studies have shown a higher incidence of hypertension during daily activities, and during exercise, in patients after surgical correction of coarctation. To the best of our knowledge, however, no data exists concerning haemodynamics, the response of arterial pressures, and the effects of medications for lowering blood pressure during exercise or during daily activities.We studied 128 patients, aged 15.6 +/- 4.3 years, to determine the response of blood pressure as we administered treatment in the attempt to achieve a normotensive state. We excluded patient with associated cardiac abnormalities, apart from those with bicuspid aortic valves. We evaluated blood pressure at rest in both the right arm and leg to establish presence of any gradient, as well as the blood pressure in the arm during exercise testing, and by 24-hour ambulatory monitoring.Atenolol was prescribed for those with elevated values of blood pressure but with a normal increment of heart rate during exercise. We prescribed Candesartan for those with elevated levels of blood pressure but with reduced increments of heart rate, specifically maximal heart rates of less than 85% of their predicted value. Both drugs were used when one alone was not effective. We found that, in young patients, candesartan provided better control of blood pressure with no side-effects, especially as demonstrated using 24-hour ambulatory monitoring, while atenolol was less effective, with more side-effects. Our experience suggests that both drugs should be used in patients who are non-responsive to monotherapy.

The influence of different surgical procedures on hypertension after repair of coarctation.

We measured resting and exercise haemodynamics, as well as 24-hour ambulatory blood pressure, so as to study the influence on development of hypertension in children after repair of coarctation by either construction of a subclavian flap or end-to-end anastamosis. The patients in both groups were studied a mean time of 13 years after surgery. Thus, we divided 43 children who had undergone surgical repair of coarctation, and who were not on antihypertensive therapy, into a group of 22 patients who had undergone subclavian flap repair, with a mean age of 14 plus or minus 2.6 years, and another group of 21 patients undergoing end-to-end anastomosis, with a mean age of 13.5 plus or minus 3.9 years. We examined blood pressure at rest and during exercise, along with the measurement of cardiac output using impedance cardiography, and during 24-hour ambulatory monitoring. We recorded systolic and diastolic blood pressures, pulse pressure, cardiac output and total peripheral vascular resistance at rest and at peak exercise. During ambulatory monitoring, we measured mean pressures over 24 hours, in daytime and nighttime, 24-hour pulse pressure, and 24-hour mean arterial pressure. Student's t test was used to judge significance, accepting this when p was less than 0.05. The group repaired using the subclavian flap showed significantly disadvantageous differences for diastolic blood pressure at rest, systolic blood pressure at peak exercise and for 24-hour systolic and diastolic blood pressure, 24-hour mean arterial pressure, and daytime and nighttime systolic blood pressure during ambulatory monitoring. Our findings suggest that, after repair using the subclavian flap in comparison to end-to-end anastomosis, patients show a higher incidence of late hypertension, both during exercise and ambulatory monitoring. The data indicate different residual aortic stiffnesses, these being lower after end-to-end anastomosis, which may be due to the greater resection of the abnormal aortic tissue when coarctation is repaired using the latter technique.

Blood pressure in the long-term follow-up of children with hemolytic uremic syndrome.

The hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure (ARF) in young children. Most patients recover from the acute phase of the illness but they may develop arterial hypertension(AH) after many years, even in the absence of signs of renal impairment during short-term follow-up. In this study, we performed casual blood pressure (BP) measurement, 24-h blood pressure monitoring (ABPM), and a Bruce walking treadmill study (ET) in 24 children (aged 5-15 years, 13 males, 11 females) with a history of HUS and normal renal function during follow-up (median 5.8 years, range 1.8-12.4 years). There were 22 children(91%) with prodromal diarrhea associated with HUS and 20 (83%) underwent dialysis during the acute illness. All children had normal casual BP measurement. Of 13 children (54%) with normal ABPM, 5 patients (38%) had an abnormal BP response during the ET study. There were 4 (58%) of the 7 patients with AH by ABPM (29%)and an abnormal BP response during ET. These findings suggest that ET could be a useful means of identifying children with a history of HUS that could be at risk of future AH even if they had normal renal function, casual BP, and ABPM during long-term follow-up. These results should be confirmed with a large prospective clinical study.

Exercise-induced left bundle branch block in a young female athlete.

An 11-year-old female, in apparent good health, was referred to our Institute because of exercise-induced left bundle branch block detected during a Master's step test performed to obtain the clearance for competitive sport. The tests that we performed to investigate the possible causes were all negative. We suspect, however, that the left bundle branch block is the initial sign of cardiomyopathy. If our suspicions are correct, close follow-up is important to chart the possible progression of the disease.

Exercise blood pressure response, cardiac output and 24-hour ambulatory blood pressure monitoring in children after aortic coarctation repair.

BACKGROUND: The aim of this study was to assess blood pressure at rest, the response to exercise and the 24-hour ambulatory blood pressure monitoring (ABPM) profile in children operated for aortic coarctation. METHODS: Twenty children were operated upon for aortic coarctation. The patients' data were compared with those obtained from 19 healthy controls of the same age. Treadmill exercise testing was performed and cardiac output was determined using the acetylene-rebreathing method and indexed for the body surface area; ABPM was performed only in the patients group. The main outcome measures were the time of exercise, systolic (SBP) and diastolic (DBP) blood pressure both at rest and at peak exercise, maximal heart rate, total peripheral vascular resistance at rest and at peak exercise, and the pulse pressure (PP = SBP-DBP) at rest, at peak exercise and at ABPM. The Mann-Whitney test (non-parametric) and linear regression analysis were used when appropriate. RESULTS: Patients compared with healthy controls showed significant differences in SBP and PP at rest, and in DBP, cardiac index, total peripheral vascular resistance and PP at peak exercise. In the patients group only, linear regression analysis showed a significant correlation between PP and cardiac output, both at rest and at peak exercise, and between the arm-leg gradient at rest and PP at ABPM. CONCLUSIONS: These findings suggest that blood pressure abnormalities could be due both to the altered baroceptor reflex control mechanism, resulting in cardiac output and total peripheral vascular resistance abnormalities, and to the progressive increase in resistance during exercise at the site of the repair, resulting in the higher PP, that may be related to a local loss of the natural aortic elasticity.

Sonographic biometry of liver and spleen size long after closure of abdominal wall defects.

UNLABELLED: Little is known about the fate of the liver and spleen after closure of the abdominal cavity in patients with abdominal wall defects (AWD). Therefore, counselling families for long-term follow-up and in the case of surgery for acute disease, pregnancy or trauma may be difficult. A total of 18 patients ranging in age from 7 to 18 years, with AWD closed at birth, underwent ultrasound evaluation of liver and spleen size by determination of the index of liver size (ILS) and splenic volume (SV). These values were then correlated with some anthropometric parameters such as body mass index (BMI) and weight; correlation was also sought with some clinical features such as type of defect and direct or staged closure. Nearly all subjects exhibited weight above and BMI below the 50th percentile for age. ILS and SV were significantly above normal limits in all cases and no difference was found with regard to the type of defect. CONCLUSION: In patients having undergone surgery for abdominal wall defects, liver and spleen usually regain their normal shape and position even though size and volume appear to be larger than in normal controls.

Total peripheral vascular resistance in pediatric renal transplant patients.

BACKGROUND: Abnormal cardiovascular reactivity at rest and during physical exercise may be a risk factor for left ventricular hypertrophy (LVH) in pediatric renal transplanted (Tx) patients. Data on total peripheral vascular resistance (TPR) are not available. METHODS: Eleven renal Tx patients treated with cyclosporine (7 females and 4 males; mean age 14.6 +/- 3.3 years; mean time since transplantation 43 +/- 35 months) were evaluated for 24-hour blood pressure (BP), TPR and echocardiographic left ventricular mass (LVM). TPR values of patients were compared with data of a group of 11 healthy controls matched for sex and age. RESULTS: Twenty-four-hour ambulatory blood pressure monitoring showed that all but one patient had normal daytime BP values and six patients showed a reduced or inverse nocturnal dip. LVH was found in 72% of the patients. In comparison with healthy controls, patients showed significantly elevated TPR at rest and during exercise suggesting an increased vascular tone. The degree of LVH in these patients is severe and appears disproportionate to the BP values. CONCLUSION: The high incidence of LVH can reflect an augmented cardiovascular reactivity associated with a disturbed circadian pattern. The increase in TPR and the reduction of the nocturnal fall of BP also might contribute to the development of LVH in young renal Tx patients.