Thierry Sluysmans

Infantile dilated cardiomyopathy : relation of outcome to left ventricular mechanics, hemodynamics, and histology at the time of presentation

BackgroundFor patients with acute dilated cardiomyopathy, definition of prognosis and of clinical features predictive of outcome is particularly important due to the availability of cardiac transplantation and other innovative treatment strategies. Methods and ResultsWe reviewed our experience with 24 children under 2 years of age with dilated congestive cardiomyopathy to determine outcome and potential predictive variables. Clinical, serological, ECG, echocardiographic, hemodynamic, and histological findings were analyzed. Idiopathic cardiomyopathy or myocarditis constituted 29% of the patients presenting with congestive heart failure without structural heart disease. Among these patients, 45% recovered completely, 25% survived with persistent left ventricular dysfunction, and 30% died. All except one of the deaths occurred during the first 2 months after presentation. Poorer outcome and higher mortality were associated with a more severely depressed left ventricular ejection fraction and/or a more spherical left ventricular shape at presentation. Histological evidence of myocardial inflammation was a favorable prognostic indicator, whereas histological evidence of endocardial fibroelastosis was associated with a poor outcome. During the recovery phase, diastolic volume fell rapidly. Ventricular mass was elevated from the earliest observations and fell more slowly, with persistent elevation of the mass-to-volume ratio up to 2 years. Function and contractility improved over the first several months in most patients who recovered, although in occasional patients continued improvement was seen for as long as 2 years after presentation. ConclusionsHistological and echocardiographic features can be used to identify patients at particularly high risk for death. To have any impact on outcome, decisions about cardiac transplantation must be reached rapidly, since almost all deaths occurred within the first 2 months after presentation. Recovery of function is often rapid, but continued improvement may be seen for as long as 2 years.

Natural history and patterns of recovery of contractile function in single left ventricle after Fontan operation.

BackgroundBefore the era of the Fontan procedure, the typical course of patients with single left ventricle (LV) consisted of heart failure and death during the second or third decade of life. Despite the advent of effective palliative therapy, ventricular dysfunction remains a significant clinical problem for these patients. Methods and ResultsTo investigate the causes of ventricular dysfunction in these patients and to determine whether Fontan-type repair reverses deterioration of LV function, the ventricular dimensions, volume, shape, wall stress, and systolic function were determined by echocardiography in 84 patients 0.2–35 years old with double-inlet single LV or tricuspid atresia. Measurements were obtained in 67 patients after palliation (arterial shunt or pulmonary artery band) and in 47 patients a median of 4.4 years after a Glenn (n=9) or a Fontan operation (n=38). Before a Fontan procedure, ventricular volumes were 2 to 3 times normal. Ventricular afterload, assessed as circumferential and meridional end-systolic wall stress, became abnormal after 2 years of age. With age, LV shape changed progressively from ellipsoidal to spherical, as indicated by the decrease in long axis: short axis ratio from normal (1.9) toward unity. Concomitantly, the ratio of circumferential to meridional end-systolic wall stress fell from 1.3 to unity, the ratio of a sphere at equilibrium. This age-related change in shape and load occurred in concert with progressive deterioration of LV systolic function and contractility. Aortic oxygen saturation, an indicator of pulmonary blood flow and therefore volume work in single-ventricle physiology, was inversely and independently correlated with contractility. In the group of patients in whom a Glenn or a Fontan operation was performed at < 10 years of age, ventricular dimensions, volumes, and wall stress diminished and LV function and contractility improved after surgery (p < 0.001). In patients undergoing surgery after 10 years of age, few had improvement of LV function after surgery. Postoperative ventricular function and contractility were inversely related to age at surgery and to aortic oxygen saturation measured before surgery. ConclusionsAlthough Fontan-type repair of single ventricle early in life is associated with reversal of the abnormal contractile mechanics associated with age and volume load, this capacity for recovery diminishes with age at surgery.

Bulboventricular foramen size in infants with double-inlet left ventricle or tricuspid atresia with transposed great arteries: influence on initial palliative operation and rate of growth.

Bulboventricular foramen obstruction may complicate the management of patients with single left ventricle. Bulboventricular foramen size was measured in 28 neonates and infants greater than 5 months old and followed up for 2 to 5 years in those patients whose only systemic outflow was through the foramen. The bulboventricular foramen was measured in two planes by two-dimensional echocardiography, its area calculated and indexed to body surface area. One patient died before surgical treatment. The mean initial bulboventricular foramen area index was 0.94 cm2/m2 in 12 patients (Group A) in whom the foramen was bypassed as the first procedure in early infancy. The remaining 15 patients underwent other palliative operations but the bulboventricular foramen continued to serve as the systemic outflow tract. There was one surgical death. Six (Group B) of the 14 survivors developed bulboventricular foramen obstruction during follow-up (mean initial bulboventricular foramen area index 1.75 cm2/m2). The remaining eight patients (Group C) did not develop obstruction during follow-up and had an initial bulboventricular foramen larger than that in the other two groups (mean initial bulboventricular foramen area index 3.95 cm2/m2). All patients with an initial bulboventricular foramen area index less than 2 cm2/m2 who did not undergo early bulboventricular foramen bypass developed late obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)

Early Balloon Dilatation of the Pulmonary Valve in Infants With Tetralogy of Fallot Risks and Benefits

BACKGROUNDnBalloon dilatation, an established treatment for pulmonary valve stenosis, remains a controversial procedure in tetralogy of Fallot.nnnMETHODS AND RESULTSnBalloon dilatation of the pulmonary valve was performed in 19 infants with tetralogy of Fallot. Its effects on the severity of cyanosis, the growth of the pulmonary valve and pulmonary arteries, and the need for transannular patching were evaluated. Clinical, echographic, angiographic, hemodynamic, and operative data were analyzed. The procedure was safe in all, without significant complications. After balloon dilatation, systemic oxygen saturation increased from a mean value of 79% to 90%. This increase proved to be short-lasting in 4 patients, who required surgery before the age of 6 months. Balloon dilatation increased pulmonary annulus size in each case, from a mean value of 4.9 to 6.9 mm (P < .001). This gain in size remained stable over time, with a mean Z score of -4.8 SD before dilatation, -3.1 SD immediately after the procedure, and -2.7 SD at preoperative catheterization (P < .001). Pulmonary artery dimensions remained unchanged immediately after balloon dilatation but increased at follow-up from a Z score mean value of -2.5 to -0.06 SD and from -2.2 to 0.04 SD for right and left pulmonary arteries, respectively (P < .001). At the time of corrective surgery, the pulmonary annulus was considered large enough to avoid a transannular patch in 69% of the infants. This represented a 30% to 40% reduction in the need for a transannular patch compared with the incidence of transannular patch expected before balloon dilatation.nnnCONCLUSIONSnPulmonary valve dilatation in infants with tetralogy of Fallot is a relatively safe procedure and appears to produce adequate palliation in most patients. It allowed the growth of the pulmonary annulus and of the pulmonary arteries, resulting in a mean gain of 2 SD for those structures.

Impact of the permanent ventricular pacing site on left ventricular function in children: a retrospective multicentre survey.

Background Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. Objective In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated. Methods Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age <18u2005years were retrospectively collected from patients undergoing chronic ventricular pacing (>1u2005year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics. Results From 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n=147), RV endocardium (RVendo, n=113) or LV epicardium (LVepi, n=37). LVFS was significantly affected by pacing site (p=0.001), and not by maternal autoantibody status (p=0.266). LVFS in LVepi (39±5%) was significantly higher than in RVendo (33±7%, p<0.001) and RVepi (35±8%, p=0.001; no significant difference between RV-paced groups, p=0.275). Subnormal LVFS (LVFS<28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS≥28%) in all LVepi-paced children (p=0.049). These results are supported by the findings for LVEF (n=122): LVEF was <50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was ≥50% in 17/18 (94%) LVepi-paced patients. Conclusion In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing.

Very long chain acyl-coenzyme A dehydrogenase deficiency in two siblings: evolution after prenatal diagnosis and prompt management.

A boy had neonatal seizure, lethargy, and metabolic acidosis at presentation. He recovered completely, but the recurrence of a similar episode with associated cardiomyopathy and dicarboxylic aciduria at 10 months of age led to the recognition of a fatty acid oxidation defect. A diagnosis of very long chain acyl-coenzyme A dehydrogenase deficiency was later made by enzyme assay in culture fibroblasts from this child, as well as in cultured amniotic cells from a sibling fetus. This prenatal diagnosis forestalled neonatal injury by close clinical and metabolic monitoring of the second infant. Early diagnosis and management should potentially improve the generally poor prognosis for patients with very long chain acyl-coenzyme A dehydrogenase deficiency.

Long-Term Results of Balloon Valvuloplasty as Primary Treatment for Congenital Aortic Valve Stenosis: a 20-Year Review

AbstractnIn the presence of new surgical techniques, the treatment of congenital valvular aortic stenosis is under debate. We reviewed the results and late outcomes of all 93 patients aged 1xa0day to 18xa0years, treated with balloon valvuloplasty (BAV) as first-line therapy for congenital aortic valve stenosis in our center from January 1991 to May 2012. Mean age at procedure time was 2.4xa0years; 37 patients underwent BAV at agexa0≤30xa0days (neonates), 29 patients at agexa0≥1xa0month andxa0<1xa0year (infants), and 27 patients were older than 1xa0year (children). The invasive BAV peak-to-peak aortic valve gradient (mean 59xa0±xa022xa0mmHg) was immediately reduced (mean 24xa0±xa012xa0mmHg). The observed diminution of gradient was similar for each age group. Four patients had significant post-BAV AI. Mean follow-up after BAV was 11.4xa0±xa07xa0years. The last echo peak aortic gradient was 37xa0±xa018xa0mmHg and mean gradient was 23xa0±xa010xa0mmHg, and two patients had significant AI. Actuarial survival for the whole cohort was 88.2 and 72.9xa0% for the neonates. All infants, except one, and all children survived. Sixty-six percent of patients were free from surgery, and 58xa0% were free from any reintervention, with no difference according to age. Freedom from surgery after BAV at 5, 10, and 20xa0years, respectively, was 82, 72, and 66xa0%. Our study confirms that BAV as primary treatment for congenital AS is an efficient and low-risk procedure in infants and children. In neonates, the prognosis is more severe and clearly related to “borderline LV.”

Midterm Results of the Ross Procedure in a Pediatric Population: Bicuspid Aortic Valve Is Not a Contraindication.

Our objective was to analyze retrospectively the short- and midterm results of the Ross operation in children and the impact of bicuspid aortic valve (BAV) disease on outcome. From 1991 to 2003, 41 patients (26 male, 15 female) underwent a Ross procedure. Aortic disease was congenital in all but one. Sixty-six percent had BAV. Mean age at operation was 10.13xa0±xa05.6xa0years (range, 0.4–18.3xa0years). Root replacement technique was performed in all but two (inclusion technique). There were two early deaths. Mean follow-up was 6xa0±xa03.8xa0years (range, 0.1–14xa0years). The autograft (neo-aorta) presented absent, trivial, mild, and moderate regurgitation in 42%, 46%, 10%, and 2%, respectively, at latest follow-up. Root dilation was seen in 64% of the patients (mean Z-score, +3.53xa0±xa00.04). Four patients (9%) required allograft replacement, two for endocarditis and two for stenosis. Allograft stenosis (gradient >20xa0mmHg) was detected in 44% of the remaining patients, without symptoms or the need for reintervention. Estimated freedom from allograft replacement at 5 and 10xa0years was 97% and 89%. Left ventricular dimensions and function were normal in all patients. No difference was found between patients with BAV and those with tricuspid aortic valves in aortic regurgitation or root dilation. BAV was not identified as a risk factor for root dilation. In conclusion, the Ross operation remains an excellent option for aortic valve replacement in children. BAV is not associated with a worse outcome and is not a risk factor for aortic root dilation at medium-term follow-up. Long-term follow-up is, however, required.

A tear of the right ventricular outflow tract during pulmonary valvuloplasty treated by transcatheter Sapien valve implantation

A 74-year-old woman was treated by balloon pulmonary valvuloplasty for a symptomatic restenosis 30 years after surgical commissurotomy. The valve dilatation was complicated by a rupture of the right ventricular outflow tract, treated in emergency by a covered stent implantation. The hemodynamic situation was improved, but the free pulmonary regurgitation was leading to a symptomatic right ventricular enlargement. Because surgery was not a good option in this patient at high risk, restoration of pulmonary valve competence was performed by a transcatheter Sapien valve implantation. Transcatheter approach allowed to treat the severe complication of pulmonary valvuloplasty without risk associated with an emergent and redo surgery in a high-risk patient.

Evaluation cardiovasculaire de l'enfant sportif.

Although rare, sports related sudden cardiac deaths in children and adolescents justify the search for risk factors in any child or adolescent who wishes to practice sports. Each time that history and careful clinical cardiovascular examination point to a possible cardiovascular abnormality, an electrocardiogram and an echocardiography must be performed. Exercise testing is useful to appreciate the cardiovascular tolerance, either in normal subjects or in subjects with a cardiovascular abnormality; its interpretation requires good knowledge and understanding of hemodynamic responses to exercise. Indications, risks and procedures of exercise testing are discussed with reference to exercise physiology.