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PubMed2006

The role of the psychologist in adult congenital heart disease.

In addition to monitoring and treating the cardiac disease, patients benefit from health professionals recognizing and managing the potential psychosocial consequences of growing up with congenital heart disease. Working groups from Europe and North America have emphasized the benefit of inclusion of specialized mental health care for adult congenital heart disease (ACHD) patients. This article reviews the evidence that ACHD patients have special and unique psychosocial needs and outlines ways in which psychologists can be integrated into multidisciplinary ACHD care teams. There are three professional domains in which clinical health psychologists can contribute to an ACHD team: provision of clinical services, multidisciplinary research, and professional education. Considerations for incorporating psychology into ACHD teams are presented.

Adolescent↗
PubMed1976

Long-term observation of cardiac arrhythmias during and after cardiac surgery. II. Congenital heart disease.

Twelve arrhythmias that occurred in conjunction with surgery for congenital heart disease were studied in a group of 38 randomly selected patients. Halothane was used for anaesthesia and procaine-magnesium-aspartate solution for cardiac arrest. Registration and analysis of rhythm disturbances were carried out at 10 different time points, spaced narrowly in the intra- and early postoperative phases, then more widely up to the 96th hour of observation. Arrhythmic incidence per case and occurrence per case and phase are given, thereby also allowing an account of transient arrhythmias. The peak occurrence of intra-operative rhythm disturbances was found at about the time of aortic cross-clamping and release (ischaemia and halothane effect). A decline in arrhythmic incidence in the 1st-6th post-bypass hours was followed by a 2nd peak in the 6th-23rd postoperative hours (electrolyte and acid-base disturbances and/or a digitalis effect). All 12 arrhythmia types of the cardiopulmonary bypass group, as well as the separately considered ventricular arrhythmias of the first "arrhythmia peak", did not reveal any significant relation to: patients' age, total anaesthesia time, total surgery time and total bypass time. It is recognized that any comparative evaluation of operative arrhythmias, and especially a study of the causes and development of "surgically induced" A-V block, is problematic.

Adolescent↗
PubMed1977

Hypoxemia and auditory reaction time in congenital heart disease.

The purpose of this study was to determine if previously documented perfomances deficits of patients with cyanotic congenital heart disease are peculiar to centrallly mediated visual tasks or are also manifested on tests of other centrally mediated sensory functions such as hearing. A simple auditory reaction time test was, therefore, performed on 239 patients with congenital heart disease, 43 of whom were cyanotic. Results indicated that (a) there is no significant relationship between level of arterial oxygen saturation and auditory RT. (b) Auditory RT for the group as a whole declines until the mid-teens and then rises, a pattern at variance with that of normal subjects. (c) The audiroty RT of females was significantly higher, i.e., slower, than that of males.

Adolescent↗
PubMed2000

Three-dimensional helical computed tomographic angiography in neonates and infants with complex congenital heart disease.

BACKGROUND: For the clinical management of patients with complex congenital heart disease (CHD), accurate evaluation of their morphologic conditions is critical. Three-dimensional (3D) helical computed tomography (CT) angiography has been used to assess the vascular system in adult patients; the indication for complex CHD, especially in the neonatal period, has not yet been defined. Therefore the purposes of our study were to determine the quality and limitations of current 3D helical CT angiography for neonates and infants with complex CHD and to assess the clinical utility of this technique. METHODS AND RESULTS: 3D helical CT angiography was performed in 17 patients with various types of complex CHD. Their median age was 41 days (range 3 days to 9 months), and mean body weight was 3.6 kg (range 2.2 to 8.5 kg). All 3D images were produced with the 3D reconstruction algorithm of shaded-surface display. Oral sedation was required in only 4 infants during the procedure. 3D helical CT angiography clearly demonstrated the shape and spatial relation of great arteries, proximal branch pulmonary arteries, anomalous pulmonary venous connections, the patent ductus arteriosus, and a shunt. The 3D information of extracardiac morphologic characteristics and 3D anatomic relation of each extracardiac structure were easily recognized by this imaging process. However, intracardiac structure could not be visualized because of blurred and/or unclear edges of the ventricular wall caused by respiratory movement. CONCLUSIONS: 3D helical CT angiography represents an important additional diagnostic tool and may become an alternative method to angiography or other noninvasive techniques used in the evaluation of extracardiac anomalies in neonates and infants with complex CHD.

Adult↗
PubMedDate not supplied

Cardiac connections: the segmental approach to radiologic diagnosis in congenital heart disease.

The segmental approach to the diagnosis and classification of congenital heart disease, which emphasizes the importance of the connections (proximal-to-distal relationships) of cardiac chambers and great vessels, is presented. The radiologic identification of great vessels and cardiac chambers and their connections is described, considering, in turn, three major segments: the atria together with the systemic and pulmonary veins, the ventricles with their atrioventricular valves and the great arteries with their outflow tracts. Cardiac and great vascular connections can be described with greatest clarity by using the atria as the starting point. The atrial situs is defined as solitus, inversus or ambiguus, the great veins connecting to the atria normally or anomalously. The ventricles may be connected to the atria in concordant or discordant fashion or a double inlet ventricle may be present. The ventriculo-arterial connections can be classified as normal, transposition, double outlet right ventricle or double outlet left ventricle. The angiocardiographic techniques and criteria that differentiate these connection disorders and identify the transitional cases between them are discussed and illustrated. A complete diagnosis must indicate not only the connections of the three major segments but also the malformations and abnormalities of spatial position that may be present. Certain associations are of value in predicting the positions and connections of the cardiac chambers and great vessels, making it possible to formulate helpful rules to aid the progress of a diagnostic study. The fallibility of such rules is discussed, emphasizing the need to define connection disorders in terms of the connections rather than in terms of malformations or of abnormalities in spatial position of the individual parts.

Angiocardiography↗
PubMed1995

Toward a molecular understanding of congenital heart disease.

BACKGROUND: This review discusses the incidence and importance of congenital heart disease (CHD), the reasons that investigation of causative mechanisms for human CHD has been slow, and the limitations of the multifactorial theory for the etiology of CHD. METHODS AND RESULTS: The molecular defects underlying three vasculopathies--Marfan's syndrome (fibrillin), supravalvar aortic stenosis, and Williams' syndrome (elastin)--and hereditary telangiectasia are presented to emphasize the role of microfibrils and extracellular matrix in the pathophysiology of these vascular defects. Animal models of CHD, including situs inversus, canine conotruncal malformations, and chick neural crest ablation, are examined to emphasize how such studies relate to human CHD, especially by pointing to single-gene defects for conotruncal malformations, candidate loci for situs inversus, and phenotypic variability caused by neural crest lesions. The crucial role of cardiac transcription factors in heart morphogenesis is emphasized by review of gene knockout studies of these factors, which cause fetal death secondary to heart maldevelopment. Several lines of evidence demonstrating genetic etiologies of human CHD are also presented, including the mapping of familial atrial septal defects, to prove that one anatomic type of CHD may be due to single-gene defects at different loci. Review of atrioventricular canal, both secondary to trisomy 21 and as an autosomal-dominant familial defect, reiterates this conclusion. The evidence that monosomy on chromosome 22 causes multiple types of CHD, including aortic arch and conotruncal defects as part of the CATCH-22 syndrome, is presented, with results supporting the idea that deletions at this site alone may cause 5% of surgically treated CHD. CONCLUSIONS: We conclude that (1) human CHD is frequently due to single-gene defects and that even sporadic defects may arise from a single-gene abnormality; (2) a common genetic defect may cause several apparently different forms of CHD; (3) elucidation of the genetic basis of CHD provides clues to normal cardiovascular developmental biology; (4) the same cardiac malformation can be caused by mutant genes at different loci; and (5) interactions of clinical investigators (cardiologists and cardiothoracic surgeons) with basic scientists should allow more rapid progress in defining the genetic basis of CHD.

Animals↗
PubMed1992

Calories count. Improved weight gain with dietary intervention in congenital heart disease.

OBJECTIVES: We assessed the nutritional status of patients with congenital heart disease (CHD) to evaluate the role of dietary intake in impaired weight for patient length. Underweight patients with CHD underwent nutritional counseling to evaluate the role of this intervention in improvement of weight for length. RESEARCH DESIGN: We prospectively evaluated a clinical protocol for nutritional assessment and counseling in patients with CHD. Eligible patients were enrolled from a cardiology clinic during a 13-month period. Initial anthropometric measurements and measurements of dietary intake of underweight and normal-weight patients were compared. Initial and follow-up measurements of underweight patients who received nutritional counseling were compared. PATIENTS: Nineteen underweight patients with CHD and 16 normal-weight patients with CHD, aged 1 month to 2 years, were studied. Exclusion criteria included noncardiac factors that could affect growth (eg, low birth weight, Down syndrome, gastrointestinal deficit, and any severe abnormality of the central nervous system). Seventeen of the 19 underweight patients underwent nutritional counseling in the presence of a parent every 2 months for 6 months. Caloric and protein intakes were maximized using high-calorie formulas. MEASUREMENTS AND RESULTS: Baseline dietary intake was lower in underweight patients than in normal-weight patients (mean percentage of the recommended daily allowance of calories, 89% vs 108%). Follow-up evaluation in normal-weight patients showed no change in percentage of ideal body weight for length. Follow-up evaluation in underweight patients showed improvement in mean dietary intake (from 90% to 104% of the recommended daily allowance of calories) and in mean percentage of ideal body weight for length after intervention (from 83.1% to 88.3%). CONCLUSION: Nutritional evaluation of patients with CHD demonstrated that underweight children had inadequate diets. Underweight patients with CHD who received nutritional counseling showed increased dietary intake and improved anthropometric measurements on follow-up.

Anthropometry↗
PubMed1988

Effect of iron deficiency on tissue oxygen delivery in cyanotic congenital heart disease.

To test the hypothesis that tissue oxygen delivery would be affected by diminished oxygen stores in cyanotic congenital heart disease, serum ferritin, transferrin saturation, hemoglobin, red cell mean corpuscular volume (MCV), red cell 2,3-diphosphoglycerate (DPG), P50, blood gases, oxygen saturations and systemic oxygen transport were measured in 29 hypoxemic infants and children. For the group, aortic saturation was 81 +/- 9%, PaO2 was 50 +/- 12 mm Hg, hemoglobin 16.2 +/- 2.1 gm/dl and systemic oxygen transport 620 +/- 145 ml/min/m2. P50 was increased above normal values (28.8 +/- 2.3 vs 26.6 +/- 1.1 mm Hg, p less than 0.01), and DPG was 2.35 +/- 0.54 mumol/ml, at the upper limits of normal for this assay. Iron deficiency was present in 8. When patients with P50 greater than or equal to 30 mm Hg and P50 less than 30 mm Hg were compared, iron stores were diminished in the high P50 group: [serum ferritin (19 +/- 8 vs 53 +/- 48 ng/ml, p = 0.0006), transferrin saturation (11 +/- 6 vs 23 +/- 11%, p = 0.003) and MCV (79 +/- 8 vs 86 +/- 4 fl, p = 0.05)]. Hemoglobin, aortic oxygen saturation, PaO2 and systemic oxygen transport were similar in both groups. In children with iron sufficiency, 15 of 21 had MCV greater than 90th percentile for age and sex (p less than 0.001 versus expected distribution). Also, MCV greater than 90th percentile for age and sex had a positive predictive value of 0.88 for iron sufficiency. This study demonstrates that diminished iron stores in cyanotic congenital heart disease are associated with a more right-shifted oxyhemoglobin dissociation curve (increased P50).(ABSTRACT TRUNCATED AT 250 WORDS)

Child, Preschool↗
PubMed2000

Location of acutely successful radiofrequency catheter ablation of intraatrial reentrant tachycardia in patients with congenital heart disease.

Intraatrial reentrant tachycardia (IART) is common after surgery for congenital heart disease (CHD). Radiofrequency (RF) catheter ablation of IART targets anatomic areas critical to the maintenance of the arrhythmia circuit, areas that have not been well defined in this patient population. The purpose of this study was to determine the anatomic areas critical to IART circuits, defined by activation mapping and confirmed by an acutely successful RF ablation at the site. A total of 110 RF ablation procedures in 88 patients (median age 23.4 years, range 0.1 to 62.7) with CHD were reviewed. Patients were grouped according to surgical intervention: Mustard/Senning (n = 15), other biventricular repaired CHD (n = 24), Fontan (n = 43), and palliated CHD (n = 6). In first-time ablation procedures, > or = 1 IART circuits were acutely terminated in 80% of Mustard/Senning, 71% of repaired CHD, and 72% of Fontan (p = NS). The palliated CHD group underwent 1 of 6 successful procedures (17%), and this patient was excluded. The locations of acutely successful RF applications in Mustard/Senning patients (n = 14 sites) were at the tricuspid valve isthmus (57%) and at the lateral right atrial wall (43%). In patients with repaired CHD (n = 18 sites), successful RF sites were at the isthmus (67%) and the lateral (22%) and anterior (11%) right atria. In the Fontan group (n = 40 sites), successful RF sites included the lateral right atrial wall (53%), the anterior right atrium (25%), the isthmus area (15%), and the atrial septum (7%). Location of success was statistically different for the Fontan group (p = .002). In conclusion, the tricuspid valve isthmus is a critical area for ablation of IART during the Mustard/ Senning procedure and in patients with repaired CHD. IART circuits in Fontan patients are anatomically distinct, with the lateral right atrial wall being the more common area for successful RF applications. This information may guide RF and/or surgical ablation procedures in patients with CHD and IART.

Adolescent↗
PubMedDate not supplied

Perioperative care of the adult with congenital heart disease in a free-standing tertiary pediatric facility.

Adult patients with congenital heart disease are presenting more frequently for cardiac surgery. Frequently, pediatric congenital heart surgeons perform these procedures at pediatric hospitals. Between July 1995 and June 2000, a retrospective review of adult patients (> or = 18 years old) who had undergone cardiothoracic operations was performed. A total of 112 operations were performed and divided into two groups--81 cardiac operations in 79 patients and 31 noncardiac operations in 23 patients. One patient had a cardiac and noncardiac operation performed. The overall early operative mortality was 6% (6/101). There were 3 late deaths. New-onset cardiac arrhythmias requiring treatment were diagnosed after 5/81 (6%) cardiac operations. Six of 79 (7%) patients were diagnosed with postoperative clinical depression. An acceptable mortality can be achieved when adult patients undergo cardiothoracic operations at a pediatric facility. New-onset arrhythmias necessitating treatment are relatively common, and postoperative clinical depression should be anticipated.

Adolescent↗
PubMed2006

Congenital heart diseases in small animals: part II. Potential genetic aetiologies based on human genetic studies.

Comparative genetics provides veterinary researchers and clinicians with invaluable information for the understanding the possible genetic aetiologies and the disease process in congenital heart defects (CHDs) of dogs and cats. Although, the demand on this type of research has increased in the veterinary field, to date no fundamental genetic studies have been reported in the veterinary literature. In this second part of a two-part review, the general features and pathogenesis of major CHDs in humans and small animals are discussed. In addition, the known genetic aetiologies in human CHDs have been considered in parallel to CHDs in small animals.

Animals↗
PubMed2006

DNA microarray analysis for human congenital heart disease.

Right ventricular hypertrophy and failure are prominent features in cyanotic congenital heart disease, tetralogy of Fallot (TF). Patients with TF require primary cardiac surgery at a very young age. To gain insight into the underlying molecular mechanisms of right ventricular hypertrophy and to identify gene(s) involved in TF, differential gene expression profile was assessed using expression-based microarray technology on right ventricular biopsies from young TF patients who underwent primary correction. By using quantitative immuno histochemistry, expression of vascular endothelial growth factor (VEGF), flk-1, and extracellular matrix (ECM) proteins (collagens and fibronectin) as well as vessel counts and myocyte cell size was evaluated in TF patients in relation to age-matched controls. Among 236 genes showing altered expression pattern in TF patients, VEGF (1.8-fold) and ECM markers were clearly upregulated (fibronectin, 2.4-fold; collagen Ialpha, 7.5-fold; and collagen III, 4.4-fold); flk-1 and most matrix metalloproteinases (MMPs) remained unchanged, except the levels of MMP-13 and -17 declined. Tissue inhibitors of metalloproteinases showed a downregulated pattern. Staining of VEGF in cardiomyocytes and of ECM proteins (fibronectin, collagen I and III) in interstitial as well as in perivascular area was increased (p < 0.01) in TF patients. Morphometric analysis revealed enhanced vascular density (p < 0.05) with unchanged wall thickness and enlarged myocyte cross-sectional areas (p < 0.01) with linear correlation (p < 0.01) with the age in TF-1 patients. We conclude that the upregulation of genes encoding VEGF and ECM proteins are the key events contributing to right ventricular hypertrophy and stunted angiogenesis in patients with TF.

Adult↗
PubMedDate not supplied

Congenital heart diseases in aged patients: clinical features, diagnosis, and therapeutic indications based on the analysis of a twenty five-year Medline search.

OBJECTIVES: The increasing aging of the population make congenital heart disease more likely to be found in aged patients. No systematic data exist on epidemiology, diagnosis, and therapy in this complex class of patients. The purpose of this study was to provide specific clinical, diagnostic, and therapeutic information concerning patients over 65 with congenital heart disease (CHDs) and to identify the most frequent CHDs in such class of patients. METHODS: A Medline search was performed to include articles related to congenital heart disease in patients over 65 in worldwide literature from January 1977 to January 2004. Follow-up studies of old, operated CHDs were excluded. The selected papers were divided and numbered on the basis of key words in the title and contents into general, diagnostic, and therapeutic topics. RESULTS: One thousand ninety-five articles met the search criteria. Atrial septal abnormalities, coronary artery anomalies, bicuspid aorta and congenital aortic valve stenosis, and patent ductus arteriosus resulted in the most cited CHDs in the elderly. Clinical manifestations included syncope, supraventricular/ventricular arrhythmias, symptoms of chronic pulmonary hypertension, and congestive heart failure. Echocardiography for the most frequent CHDs and computed tomography and magnetic resonance for complex cases were the main diagnostic tools (277, 104, and 110 citations, respectively). Catheterization plays a marginal role (68 articles). Age is not considered a contraindication to interventions; surgical and endovascular therapy appeared to be similarly useful in managing the most frequent CHDs (88 and 63 citations, respectively), whereas medical treatments were selected for most complex CHDs (71 citations). CONCLUSIONS: Patients with CHDs, especially those with low mortality in childhood, are more frequently reaching old age. New imaging techniques and endovascular treatments seem useful in the challenging management of CHDs in aged patients.

Aged↗
PubMed1991

Transesophageal echocardiography for congenital heart disease.

Surface echocardiographic imaging of small children is routinely successful in defining anatomical details and Doppler flow patterns with even the most complex congenital cardiac malformations. However, in larger children or adults, imaging is frequently limited. A recent expansion of the role of echocardiography is intraoperative epicardial imaging. Epicardial and postoperative imaging, however, have significant limitations. To avoid some of these limitations, transesophageal echocardiography has increasingly been used in the arena of congenital heart disease. The more recent development of small sized gastroscopic probes has allowed transesophageal echocardiographic assessment of congenital heart disease in children down to newborn size. As detailed studies of individual lesions are reported, it has become clear that the mere presence of a congenital heart defect is not an indication for transesophageal echocardiography in most children if imaging can be accomplished by surface examination. However, transesophageal echocardiography may be indicated for the intraoperative or postoperative assessment of that defect, particularly when repair has been difficult or is known to be associated with significant residual abnormalities. Cardiac structures encountered with horizontal and vertical imaging plane transducers have been described and should be completely familiar to the examining echocardiographer.

Child↗
PubMed2005

PTPN11 mutations play a minor role in isolated congenital heart disease.

PTPN11 missense mutations cause approximately 50% of Noonan syndrome, an autosomal dominant disorder presenting with various congenital heart defects, most commonly valvar pulmonary stenosis, and hypertrophic cardiomyopathy. Atrioventricular septal defects and coarctation of the aorta occur in 15% and 9%, respectively. The aim of this study was to determine if PTPN11 mutations exist in non-syndromic patients with these two relevant forms of congenital heart disease. The 15 coding PTPN11 exons and their intron boundaries from subjects with atrioventricular septal defects (n = 24) and coarctation of the aorta (n = 157) were analyzed using denaturing high performance liquid chromatography and sequenced if abnormal. One subject with an atrioventricular septal defect but no other known medical problems had a c.127C > T transition in exon 2, predicting a p.L43F substitution. This mutation affected the phosphotyrosine-binding region in the N-terminal src homology 2 domain and was close to a Noonan syndrome mutation (p.T42A). An otherwise healthy patient with aortic coarctation had a silent c.540C > T change in exon 5 corresponding to p.D180D. Our study showed that PTPN11 mutations are rarely found in two isolated forms of congenital heart disease that commonly occur in Noonan syndrome. The p.L43F mutation belongs to a rare class of PTPN11 mutations altering the phosphotyrosine-binding region. These mutations are not predicted to alter the autoinhibition of the PTPN11 protein product, SHP-2, which is the mechanism for the vast majority of mutations causing Noonan syndrome. Future studies will be directed towards understanding these rare phosphotyrosine binding region mutants.

Adolescent↗
PubMed2003

Acute endothelin A receptor antagonism improves pulmonary and systemic haemodynamics in patients with pulmonary arterial hypertension that is primary or autoimmune and related to congenital heart disease.

OBJECTIVE: To evaluate the acute haemodynamic effect of BQ-123, a selective endothelin A receptor antagonist, in severe chronic pulmonary arterial hypertension (PAH) of primary or autoimmune origin or related to congenital heart disease. DESIGN: Prospective open clinical study. SETTING: Cardiology tertiary referral centre. PATIENTS: 26 patients with chronic PAH were studied, with mean (SEM) age 29 (3) years (range 4-71 years), mean pulmonary artery pressure 68 (4) mm Hg, and pulmonary vascular resistance index 1694 (170) dyne x s x cm(-5). Patients were divided in three groups according to PAH aetiology: primary or autoimmune PAH (n = 12), and PAH associated with congenital heart defects with (n = 6) or without (n = 8) complete mixing. INTERVENTION: BQ-123 200 nmol/min was infused for 60 minutes in the right atrium with sequential haemodynamic measurements at 30 minute intervals. RESULTS: BQ-123 improved mean pulmonary artery pressure from 68 (4) to 64 (4) mm Hg (p < 0.05), pulmonary vascular resistance index from 1694 (170) to 1378 (145) dyne x s x cm(-5) (p < 0.001), pulmonary cardiac index from 3.0 (0.2) to 3.4 (0.3) l/min/m2 (p < 0.001), and effective cardiac index from 2.5 (0.2) to 2.7 (0.2) l/min/m2 (p < 0.01). Haemodynamic response was similar in all groups except for systemic cardiac index where a different (p = 0.0001, F = 5.53) response was observed; systemic cardiac index increased from 2.7 (0.2) to 2.9 (0.2) l/min/m2 (p < 0.001) when patients with complete mixing were excluded, in whom systemic cardiac index tended to decrease from 3.4 (1.0) to 3.0 (0.6) l/min/m2 (p = 0.06). CONCLUSIONS: Acute endothelin A receptor antagonism induces substantial haemodynamic improvement in severe chronic PAH of primary or autoimmune origin or related to congenital heart disease.

Adolescent↗
PubMedDate not supplied

Right ventricular function in congenital heart disease: pressure and volume overload lesions.

The right ventricle is often subject to both pressure and volume overload in congenital heart disease. Evaluating right ventricular function in both the native lesion and after surgery in light of these loading conditions, presents a unique challenge for investigators studying these misshapen hearts. The purpose of this article is to briefly delineate what is generally known about right ventricular function in congenital heart disease and to touch on some noninvasive imaging modalities which have helped shed some light on this matter.

Animals↗
PubMed1993

Delayed onset of alcuronium effect in children with cyanotic congenital heart disease.

The effect of alcuronium dichloride (0.3 mg/kg) was studied in seven normal children (Group A), nine with acyanotic congenital heart disease (Group B) and eight with cyanotic disease (Group C). The onset of action was recorded using an integrated electromyograph and blood samples taken for later estimation of plasma concentrations of the drug. The mean time (SD) taken to 75% suppression of twitch height was 1.3(0.8), 1.7(1.0) and 3.8(2.8) minutes, respectively, in each of the three groups. This was significantly slower in Group C compared with both other groups (P < 0.05). While six of the Group A patients and seven from Group B reached 95% paralysis within ten minutes, only two of the cyanosed children achieved this level of relaxation. However, if times to 95% relaxation were extrapolated, there was no significant difference between the groups at 4.5(3.9), 5.8(5.7) and 10.9(6.5) minutes respectively. There was a weak but statistically significant relationship between haematocrit and time to 75% blockade. Maximum twitch depression was similar in all three groups with plasma concentrations at this time being 1.6(0.7), 1.8(0.5) and 2.3(1.4) micrograms/ml respectively. Again, there was no statistically significant difference between these values. These results confirm that the clinical onset of relaxation is delayed in children with cyanotic congenital heart disease, possibly because of delayed distribution of alcuronium.

Alcuronium↗