Speech and language in Simpson-Golabi-Behmel syndrome: a case report.

Simpson-Golabi-Behmel syndrome (SGBS) is an X-linked disorder caused by a mutation of the glypican-3 gene. The physical characteristics associated with SGBS have been documented in several papers, but information on the behavioral phenotype is scarce. We report on the speech and language characteristics in an 8 year-old-boy with SGBS. The boy performed very well on formal language tests but he also demonstrated poor pragmatic skills. Speech was characterized by a distorted articulation, distorted resonance, fluency failures, and a stereotype prosody. Many more case descriptions are necessary to delineate the full range of the behavioral phenotype of SGBS.

The influence of low afterload on the nature of the stress-velocity relationship.

OBJECTIVES: Correct assessment of contractility by conventional methods during manipulation of afterload is often disappointing. To this purpose, the stress-velocity relationship offers assessment of contractility at different levels of afterload. We decided to study the influence of afterload on the nature of the stress-velocity relation. BACKGROUND: Although linear at baseline conditions in a population older than two years, data in newborns or after administration of low-dose dobutamine suggest a different nature of this relationship at low afterload. METHODS: Ten healthy piglets (five to six weeks; 11 to 13 kg) were studied. End-systolic meridional wall stress (ESWS) and rate-corrected velocity of circumferential fiber shortening (VcFc) were measured in these piglets at baseline, after balloon occlusion of the descending aorta, and at nitroprusside infusion rates of 1, 2 and 5 microg/kg/min. To eliminate inotropic influences mediated by reflex tachycardia, we subsequently studied five piglets and six adult pigs after bilateral cervical vagotomy. RESULTS: The ESWS changed from a baseline mean of 50 g/cm2 to 137 g/cm2 after balloon occlusion and to 19 g/cm2 at 5 microg/kg/min of nitroprusside. The VcFc changed from 1.19 c/s (circumference/second) to values of 0.9 c/s and 1.73 c/s, respectively. The ensuing stress-velocity regression line proved to be curvilinear instead of linear. The steeper slope at low afterload could suggest enhanced contractility compared to expected values had the relationship been linear. CONCLUSIONS: Data from young piglets and adult pigs suggest a curvilinear relationship of the stress-velocity relationship. This could probably explain some of the "hypercontractile states" encountered in conditions with low afterload.

Reduced decrease of peripheral vascular resistance during exercise in young type I diabetic patients.

OBJECTIVE: In normal subjects, peripheral vascular resistance decreases during dynamic exercise. We studied blood pressure and peripheral vascular resistance responses to dynamic exercise in young normotensive type I diabetic patients. RESEARCH DESIGN AND METHODS: Thirty adolescent diabetic patients (9-19 years of age) underwent a maximal exercise test on a cycle ergometer. In a subset of 14 patients, cardiac output was measured by a CO2 rebreathing method and peripheral vascular resistance was calculated. Twenty-four normal individuals, age and sex matched, served as control subjects. RESULTS: Diastolic blood pressure was significantly higher in diabetic patients at intermediate workload (77 +/- 2 vs. 71 +/- 1 mmHg) and peak exercise (86 +/- 2 vs. 73 +/- 2 mmHg). Peripheral vascular resistance was significantly higher in diabetic patients at intermediate workload (17.0 +/- 1.1 vs. 12.6 +/- 0.5 mmHg.l-1.min-1.m-2) and peak exercise (16.3 +/- 1.3 vs. 11.4 +/- 0.5 mmHg.l-1.min-1.m-2). There were no significant correlations with the patient's age, diabetes duration, or diabetes control. CONCLUSIONS: We observed the decrease of vasodilator response during dynamic exercise in normotensive young type I diabetic patients.

Lack of increase in stroke volume during exercise in asymptomatic adolescents in sinus rhythm after intraatrial repair for simple transposition of the great arteries.

We studied stroke volume during exercise in 12 male asymptomatic patients in sinus rhythm after intraatrial repair for d-transposition of the great arteries. Data indicate that during exercise, stroke volume did not increase in the patient group, while in control subjects stroke volume increased.

Low-dose dobutamine stress echocardiography in children and young adults.

Dobutamine stress echocardiography has become widely accepted in the evaluation of adult patients with coronary heart disease. We wanted to assess the feasibility and the physiologic responses of stress echocardiography at low doses of dobutamine in a population of normal children and adults. Once achieved, we submitted a group of post-anthracycline patients to the test to assess the sensitivity of low-dose dobutamine stress echocardiography in the detection of cardiac dysfunction. Thirty-two healthy children and young adults (19 male and 13 female subjects, median age 15 years [range 6 to 26]) were studied. After the initial study of normal subjects, we submitted a cohort of 39 patients (18 female and 21 male, aged 6 to 25 years), who completed anthracycline chemotherapy, to the same protocol. Dobutamine was infused at rates of 0.5 to 2.5 and 5 microg/kg/min and echocardiographic measurements were obtained at rest and at the end of each stage. The test could be completed in 100% of the subjects without major complications. Statistically significant differences between resting echocardiographic values of systolic and diastolic function and values at 2.5 and 5 microg/kg/min of dobutamine were found. Moreover, dobutamine revealed or enhanced differences between normal subjects and the post-anthracycline patients. Thus, low-dose dobutamine stress echocardiography is feasible and safe in older children. The test is very sensitive for the detection of subclinical cardiac dysfunction in post-anthracycline patients and could possibly assess functional myocardial reserve.

Bivariate genetic analysis of left ventricular mass and weight in pubertal twins (the Medical College of Virginia twin study).

Left ventricular (LV) hypertrophy in adults is a recognized risk factor for the subsequent development of cardiovascular morbidity. To make informed preventive health decisions it is important to understand the interaction of genes and environment on LV mass. In both children and adults, weight is a strong correlate of LV mass. We hypothesized that genetic influences common to both of these variables could in part explain the strong relation between weight and LV mass in children. In a population of 341 twins (11 years old), these questions were asked: (1) How much of the total variance of LV mass is under genetic control? (2) After accounting for weight and weight adjusted for sexual maturity, how much of the remaining variance is genetic? (3) Of the total genetic variance, what proportion is specific for LV mass and what proportion is common to both weight and LV mass? (4) How much of the correlation between these 2 variables is explained by genes common to both LV mass and weight? Univariate genetic analyses documented that genes operating at different magnitudes in boys (63%) and girls (71%) explain a significant proportion of the variance of LV mass. After removing the effect of weight and sexual maturity by regression methods, genes remain an important influence. Bivariate genetic analyses confirmed that genes common to LV mass and weight significantly influence the covariation of these variables and that greater than 90% of the correlation of LV mass and weight is due to common genes.

Cardiovascular reactivity in isometric exercise and mental arithmetic in children.

In children, we studied noninvasively the cardiovascular stress responses, including changes over time of systolic blood pressure (SBP), heart rate (HR), and stroke volume (SV) in isometric handgrip (IHG) and mental arithmetic. Specifically, we asked whether 1) these cardiovascular stress responses were different for the two stress conditions in children, 2) these responses differed in boys and girls, and 3) the anthropometric variables related to these stress responses. SV differed significantly between IHG and mental arithmetic over the entire stress period. This may reflect higher systemic vascular resistance during IHG. HR in boys was lower than in girls over the entire period of stress in both stress tests. This observation cannot be attributed to differences in conditioning, because this should not influence responses to isometric or mental stress. A larger left ventricular mass was related to higher SVs. A marked relationship was found between HR and SBP and between HR and SV. No relationship was found between SBP and SV.

Delayed elimination of digoxin antidotum determined by radioimmunoassay.

An observation of a treatment with digitalis antibodies (Fab-fragments) in a young child is presented. The elimination of this antidotum proved to be much slower than normally expected. In the patient's history, the disappearance of the Fab-fragments out of the blood lasted 142 days with a half-life of 15.6 days, whereas an elimination with a T1/2 of 28 hours is accepted. Probably there has been intracellular penetration of the antibodies into the liver, caused by concomitant diseases (Hepatitis A and B infections). An "in vitro" experiment is reported. It demonstrates the equimolar binding of the Fab-fragments for digoxin and shows that the elimination of the Fab-fragments can be established by a routine radioimmunoassay of digoxin, in an indirect way.

Simultaneous delivery of two patent arterial duct coils via one venous sheath.

A female child, 10 months of age, weighing 7.2 kg, was catheterised for closure of a patent arterial duct. Aortography was performed in the lateral projection and the minimum diameter of the arterial duct was assessed by comparing it to the size of the catheter. The duct size was estimated between 3 and 3.5 mm at the narrowest point, therefore, it was decided to deliver two 5 mm patent arterial duct coils to avoid placement of an 8 mm coil in this small child. Similar operations were subsequently performed in two further children. Simultaneous delivery of two coils via a single long venous sheath is easy, fast, and safe. This simple and inexpensive procedure can reduce irradiation and anaesthesia time.

Fixed region of nondistensibility after coarctation repair: in vitro validation of its influence on Doppler peak velocities.

After coarctectomy, local loss of distensibility is noted in addition to mild anatomic narrowing. We hypothesize that the increased Doppler peak velocities measured at the aortic isthmus in these patients partly reflect obstruction secondary to the stiff surgical scar. The hypothesis was studied in a pulsatile hydraulic model. Thirty-one patients (13.0 +/- 4.0 years of age), 10.5 +/- 4.7 years after coarctectomy by end-to-end anastomosis, were studied clinically and echocardiographically. Indexes of distensibility were calculated. The effect of isolated increased stiffness was studied in vitro with a stiff and a compliant 1:1 scale latex model of the aorta mounted in a pulsatile full-scale circulation loop. Local stiffening was obtained by a rigid ring mounted around the aorta, fitted to the dimension of the unloaded aorta. For different pressure and flow regimens, pressures and Doppler velocities were measured across the ring. Mean peak velocities at the surgical scar were 2.2 +/- 0.4 m/s. Mild anatomic stenosis was present. All distensibility indexes indicated locally increased stiffness (P <.001). In the stiff latex model, Doppler peak velocities increased from 1.89 +/- 0.04 m/s to 2.32 +/- 0.06 m/s (P <.03); in the compliant model, from 1.15 +/- 0.03 m/s to 1.79 +/- 0.05 m/s (P <.001). The increase of Doppler peak velocities depends on model compliance only and is independent of flow rate, length of the noncompliant segment, and viscosity of the perfusion fluid. Velocities do not change when semicircular stiffening is applied. We have demonstrated in vitro that isolated local nondistensibility leads to vessel narrowing during vascular distension. The relative contribution of local scar stiffness in the increase of Doppler peak velocities after coarctectomy was hereby assessed.

Exercise-induced bradycardia after Mustard repair for complete transposition.

Impairment of sinus rhythm has been reported after the Mustard procedure for complete transposition. We observed two patients who developed severe bradycardia during or after exercise. The first had a 2.8 s sinus pause in the recovery period, the second had a drop in heart rate during exercise. Both eventually had a pacemaker implanted. Exercise testing can be helpful in detecting sick sinus syndrome.

Membranous subvalvar pulmonary stenosis in complete transposition; advantage of biplane transoesophageal echocardiography for the diagnosis in a young adult.

A young adult who had previously undergone a Mustard repair for complete transposition developed symptomatic left ventricular outflow tract obstruction. Biplane transoesophageal echocardiography allowed an optimal preoperative assessment. In the longitudinal plane, a discrete calcified membrane was imaged. Consequently, a pulmonary arteriotomy was chosen for the relief of the malformation.

Endocarditis from a dental focus. Importance of oral hygiene in valvar heart disease.

Fastidiously growing bacteria more and more are recognised as a source of infectious endocarditis. Over recent years, three new cases of endocarditis caused by Actinobacillus actinomycetemcomitans were diagnosed in our institution. The rise in frequency is possibly secondary to better laboratory skills. Two patients with Actinobacillus (Haemophilus) actinomycetemcomitans endocarditis presented the classical history of preexisting valvar disease together with poor dental hygiene. The third patient had no congenital or rheumatic preexisting lesion to the valves. The distal part of a ventriculo-atrial drainage device had caused microtrauma to the tricuspid valve. The right-sided endocarditis in this patient was complicated by pulmonary septic emboli. Dental origin of the infection was very likely in this patient too. No dental procedure had been performed in the months preceding the endocarditis of our three patients. They presented endocarditis with an oral microorganism in the absence of any dental manipulation. All three had very poor dental hygiene. Better dental care could possibly have prevented this serious complication.

Limitations of Doppler echocardiography for the post-operative evaluation of aortic coarctation.

Doppler blood flow measurements and derived pressure differences, through the Bernoulli equation, are used in the diagnosis of aortic coarctation, a congenital stenosis distal to the left subclavian artery. Doppler velocities remain elevated at the coarctation site after successful repair of coarctation, leading to high Doppler derived pressure differences without significant arm-leg pressure differences. We studied this apparent contradiction of two diagnostic methods, in vivo using patient and control data, and in vitro using a hydraulic model. Clinical and echocardiographic data from 31 patients, aged 13.0 +/- 4.0, 10.5 +/- 4.7 yr after coarctectomy by end-to-end anastomosis, and 18 age-matched healthy subjects were reviewed. Doppler peak velocities at the aortic isthmus were elevated in patients (2.2 +/- 0.4 vs. 1.2 +/- 0.2m/s, P < 0.001), corresponding to significant Doppler differences (20 +/- 7 mmHg), however, without significant arm-leg pressure differences. In all patients, a mild anatomic stenosis could still be observed. Local stiffness was increased. The hypothesis that the less distensible surgical scar in post-coarctectomy patients leads to a significant dynamic obstruction in systole was validated in a latex model of the aorta. Rigid rings (0.5-1.5 cm), matching the unloaded aortic diameter, were mounted around the aorta. Under loading conditions, Doppler peak velocities increased by 40 +/-7%, yielding Doppler differences of 21 +/- 3 mmHg, without a significant pressure drop. An alternative expression to calculate pressure differences, using both velocity and geometric information, was validated in the model. In conclusion, post-operatively, Doppler velocities remain elevated due to a mild anatomical and significant dynamic narrowing, but the specific geometry, resembling a tubular hypoplasia rather than an abrupt stenosis, permits an almost complete pressure recovery explaining the occurrence of Doppler differences in disagreement with the negligible arm-leg pressure difference.

Membranous subvalvular pulmonary stenosis in complete transposition of the great arteries: usefulness of serial exercise testing.

A 22-year-old male who had Mustard repair for complete transposition presented with progressive exercise intolerance, documented by a gradual decrease in exercise capacity on cycle ergometer. Cardiac catheterization and angiography demonstrated subvalvular pulmonary stenosis. After surgical relief of the obstruction, exercise capacity returned to previous level.

Cardiorespiratory variables during a continuous ramp exercise protocol in normal young adults.

The purpose of the present study was to determine whether the cardiorespiratory variables measured during an exercise test with a continuously increasing workload (ramp) protocol are reproducible and to compare them to the values obtained with a step-wise incremental (James) protocol. Twenty normal adolescents and young adults performed two exercise tests on a cycle-ergometer, one with each protocol, and twelve of these subjects additionally performed a second identical ramp test. The results show that the cardiorespiratory variables measured during exercise with ramp protocol are reproducible and that peak values are not different from those obtained with step-wise incremental exercise protocol, except for a higher peak power. At intermediate equivalent workloads, there were significant correlations between cardiorespiratory variables measured in steady-state conditions with the incremental protocol and those obtained in non-steady-state conditions with the ramp protocol.

Entrapment of a guide wire during percutaneous occlusion of a coronary artery fistula.

Coronary artery fistulas are extremely rare and coil occlusion by intervention techniques seems to be the therapy of choice. We describe the case of a 3-month-old infant with a coronary artery fistula. During occlusion of the fistula a coronary guide wire got entrapped in a small coronary branch, but could be successfully retrieved with a microsnare without damage to the heart. The microsnare technique prevented rupture of the guide wire.

[Exercise hypertension in children after surgical repair of treated ventricular and atrial septal defects]. / Hypertension artérielle à l'effort chez les enfants opérés de communication interventriculaire et de communication interauriculaire.

The blood pressure profile during exercise of children who have undergone surgery for left-to-right intracardiac shunt is not well documented. The aim of this study was to measure the peak blood pressure during dynamic exercise stress testing in children operated on for atrial or ventricular septal defects and to compare the results with those of normal children and children operated on for tetralogy of Fallot. Forty eight cases of atrial septal defect, 53 cases of ventricular septal defect and 33 cases of tetralogy of Fallot aged 5 to 14 years underwent maximal exercise stress testing on a treadmill using a modified Bruce protocol, one to ten years after the surgical repair. The heart rate, blood pressure and electrocardiogram were recorded. The duration of the test was used to judge effort tolerance. In order to compare children of different ages and sizes, the relative values were calculated using the following formula: patient value minus the mean value of the control group of the same age divided by the standard deviation of this group. At rest before exercise, there was no difference between the blood pressure of patients operated on for a left-to-right shunt and of the control group of normal children. However, the maximum systolic blood pressure during exercise was higher in patients who had undergone surgery for a left-to-right shunt than in the controls. The differences were only 0.42 standard deviations in ventricular septal defects and 0.61 standard deviations in atrial septal defects, but they were statistically significant (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Dilated cardiomyopathy caused by a novel TNNT2 mutation-added value of genetic testing in the correct identification of affected subjects.

Diagnosing familial dilated cardiomyopathy requires careful family history taking and clinical evaluation in first degree relatives. Based on the results of these findings the diagnosis may be established in the proband. However, due to the age-dependent expression of the disease, doubt may persist regarding the exact status of other family members, especially in young individuals. Here we present a family with DCM in whom we identified an underlying cardiac troponin T (TNNT2) mutation. Genetic testing was essential for the detection of asymptomatic carriers as well as for exclusion of the disease in other family members.