Renal Involvement in Patients with Congenital Cyanotic Heart Disease

ABSTRACT. Patients with congenital cyanotic heart disease may develop a glomerulopathy with proteinuria and impaired renal function. In order to investigate this problem we conducted a study on 27 patients with uncorrected cyanotic heart disease who were between 1 day and 25 years old. As a consequence of hypoxaemia haematocrit was elevated to 57%. Proteinuria was above 150 mg/day/1.73 m² body surface in 12 patients. Only one of 9 children under 10 years of age had pathological proteinuria presenting as isolated albuminuria. Seven out of 10 patients between 11 and 20 years had an elevated proteinuria with a glomerular pattern. Creatinine clearance was normal in these patients. All four patients above 20 years of age had a considerable glomerular proteinuria with a mean excretion of 5.7 g/24 h/1.73 m² body surface. These patients suffered additionally from chronic cardiac failure and creatinine clearance was below the normal range. There was a clear relationship between pathological proteinuria and age of the patients and thus duration of hypoxaemia. Patients with pathological proteinuria had a significant higher erythrocyte count (7.3±2 1.3 vs. 5.6±1.4 10¹²/l p <0.01) and a lower mean corpuscular haemoglobin. In summary, children with persistent congenital cyanotic heart disease have substantial risk of developing a glomerulopathy if the cyanosis remains unchanged for more than ten years.     

Gentamicin Dosing for Pediatric Patients with Congenital Heart Disease

Pediatric patients with congenital heart disease can have physiologies that alter the pharmacokinetics of certain medications, such as aminoglycosides. Currently, no literature describes the appropriate dosing of aminoglycoside antibiotics for infants and children with congenital heart disease. Patients were identified through the pharmacy and laboratory computer systems. Patients were included in the study if they were younger than 18 years, received gentamicin on the acute-care (nonintensive care) cardiology floor at the authors’ institution, had structural congenital heart disease, and had a peak and trough level obtained at about the third dose or later. Cohort achievement of therapeutic peak and trough concentrations based on standard dosing guidelines was evaluated. The inclusion criteria were met by 48 patients (31 boys). Eight patients (17%) had baseline cyanosis. Cardiac surgery was performed for 23 patients (48%) during the same admission at which aminoglycoside therapy was initiated. A total of 27 patients (56%) received at least one other nephrotoxic medication at the time of aminoglycoside therapy. Six patients had undetectable serum trough levels. A therapeutic peak concentration was not achieved by 16.7% of the cohort, and 7.1% of the cohort did not achieve a therapeutic trough concentration. Pediatric patients with congenital heart disease may require alterations in gentamicin dosing. Close pharmacokinetic monitoring of aminoglycoside therapy for these patients is warranted to ensure attainment of goal concentrations.     

Cumulative Radiation Exposure in Pediatric Patients with Congenital Heart Disease

Certain pediatric patients undergoing surgery for the most severe forms of congenital heart disease are exposed to high doses of ionizing radiation. The amount of cumulative radiation exposure from all modalities has not yet been evaluated. The purpose of our study was to evaluate the cumulative radiation exposure in a contemporary cohort of patients with congenital heart disease undergoing single-ventricle palliation. This is a single-center, retrospective study of pediatric patients undergoing Fontan completion between May 2005 and May 2010. Radiation exposure from all procedures including cardiac catheterizations, computed tomography (CT) scans, plain film radiography, and nuclear medicine scans was evaluated. Radiation dose was calculated as the dose area product (μGy m²) and was measured in all cardiac catheterizations, CT scans, and other imaging modalities. Seventy patients who underwent Fontan completion at a mean age of 3.6 ± 1.5 years (range 1.4–8 years) were included in the study. Mean number of chest X-rays was 32 ± 8 (range 10–285) with a mean cumulative total exposure of 1,320 μGy m² (range 480–12,960) per patient. Mean number of cardiac catheterizations was 2.45 ± 1.3 (range 1–8), and mean fluoroscopy and cine angiography exposures per case were 1,103 ± 245 and 1,412 ± 273 μGy m² giving a mean cumulative exposure of 9,054 μGy m² (range 2,515–201,200) per patient for all catheterizations. Mean number of CT scans performed was 0.44 ± 0.4 (0–11), and the mean exposure was 352 μGy m², giving a mean cumulative total of 154 μGy m² (range 0–3,872) per person. A total of five lung perfusion scans were carried out. Radiation exposure in patients with congenital heart disease undergoing single-ventricle palliation is quite variable. Most of the exposure to ionizing radiation occurs during cardiac catheterization. Strategies to utilize other imaging modalities such as MRI would decrease exposure in this particular group of patients who may be particularly vulnerable to its side effects.     

Neuropathology in Patients with Congenital Heart Disease and Down Syndrome

This report examines the relationship between congenital heart disease (CHD) and neuropathological findings in three groups of patients: Down syndrome (45 cases), isolated CHD (296 cases), and CHD with multiple anomalies (92 cases). The increase in brain weight in Down syndrome was similar to control standards up to 1 year of age, after which it was less than normal. Among the three groups, there were differences in frequency in cyanotic CHD, history of operation, and macroscopic and microscopic brain malformations. The incidence of calcification in the brain was increased in Down syndrome. Nine children out of the total cohort had cerebrovascular abnormalities. Although CHD is frequent in Down syndrome, the cerebrovasculature is spared; only infrequent minor abnormalities of the circle of Willis were detected.     

Outcomes of Aortopexy for Patients With Congenital Heart Disease

Aortopexy is a surgical procedure in which the aortic arch is fixed at other structures, thus widening the interaortic space. This study aimed to evaluate the outcome of aortopexy by means of chest computed tomography for patients with congenital heart disease. The study retrospectively reviewed the medical records of 16 patients with congenital heart disease who had undergone aortopexy by compressed airway. The severity of compressed bronchus before aortopexy, immediately after aortopexy (≤1 month), and after the patient had grown up were compared. To estimate the efficacy of the aortopexy, the interaortic distance index was calculated. Of the 16 patients, aortopexy was performed at the ascending aorta in 7, at the descending aorta in 7, and at the transverse arch in 2. The diameter ratio between the narrowest bronchus and the trachea was improved after aortopexy, as was the diameter ratio before aortopexy versus immediately after aortopexy (n = 9; p = 0.018) and the diameter ratio before aortopexy versus after the patient had grown up (n = 11; p = 0.006). Also, the interaortic distance index was increased after aortopexy, as was the diameter before aortopexy versus immediately after aortopexy (n = 9; p = 0.039) and the diameter before aortopexy versus after the patient had grown up (n = 11; p = 0.014). The study had one case of mortality due to sepsis. As shown by the results, aortopexy in patients with a compressed airway between arches is a useful surgical option. Such a compressed airway between arches should be considered for patients with an unusual clinical course before and after open heart surgery.     

Radiofrequency Catheter Ablation of Tachycardia in Patients with Congenital Heart Disease

Patients with anomalies of the heart frequently suffer from arrhythmias that either are associated with a congenital heart defect or result from the course of the disease. For most of the bradyarrhythmias, appropriate timing of the initiation of treatment is more challenging than its eventual execution. In the case of tachycardias, technical aspects of treatment require more attention because the often imperative impact such tachycardias have on quality of life, morbidity, and mortality determine intervention timing. Increasingly, interventional electrophysiology is turned to as a potentially definitive and substrate-related treatment because of antiarrhythmic drug therapy's failure to prevent arrhythmia recurrences and the potential detrimental side effects from drug therapy seen in this particular patient population. Using the experience gained during the past 10 years in the treatment of patients with arrhythmias but without associated structural heart disease, several groups reported their results and difficulties with the application of such therapy to patients with congenital heart defects. In this report, we summarize our hospital's experience with transcatheter radiofrequency current application for treatment of various types of tachyarrhythmias in 139 children and adults with congenital heart defects, emphasizing the current limitations of such therapy and addressing the potential benefits expected from future technology. Patient ages ranged from 5 months to 76 years (mean 25.3 ± 17.7 years), including 56 children and adolescents less than 16 years of age. At least one attempt at surgical palliation or correction was made in 93 patients; the remaining 46 patients had no surgical intervention attempts. A total of 225 different tachycardias were found, 93 of which were based on a congenital arrhythmogenic substrate (e.g., an accessory pathway). Acquired substrates (e.g., scars or myocardial fibrosis) gave rise to the remaining 132 tachycardias. Radiofrequency current ablation (183 sessions) successfully treated 121 of 139 patients. Within a follow-up period of 21 months a recurrence of the intrinsically treated tachycardia was seen in 24 patients (10.7%); 13 of the 24 underwent a successful repeat session. There were no significant procedure-related complications. Young and adult patients with congenital heart disease can be safely and successfully treated for tachycardias with the use of radiofrequency current ablation. Because such treatment meets the specific needs of this patient group, early consideration for this therapy is recommended.     

Late Pulmonary Valve Replacement in Congenital Heart Disease Patients Without Original Congenital Pulmonary Valve Pathology

Many congenital heart defects with pulmonary valve pathology are repaired or palliated in childhood. It is anticipated that these patients will need subsequent pulmonary valve replacement due to the pulmonary regurgitation or right ventricular dilation/failure that results from their original operation. Interestingly, some patients with prior congenital heart surgery and no congenital pulmonary valve pathology require pulmonary valve replacement in adulthood. The current study analyzed this subset of patients. The pediatric and adult congenital cardiac surgical databases at a large academic center were reviewed from 2001 to 2008 for pulmonary valve replacements. Patients without congenital pulmonary valve disease were identified. Preoperative, operative, and postoperative data were analyzed. Between 2001 and 2008, five patients with congenital heart disease but no pulmonary valve pathology underwent late pulmonary valve replacement. The initial congenital diagnoses were coarctation/ventricular septal defect (n = 3), complete atrioventricular septal defect (n = 1), and anomalous left coronary artery from the pulmonary artery (PA) (n = 1). All five patients had undergone main PA manipulation during their previous operations. Four of these patients had received PA banding and debanding, and one had received a Takeuchi tunnel repair and revision. All the patients underwent pulmonary valve replacement secondary to pulmonary regurgitation and right ventricular dilation. The average time from the last previous operation to the time of pulmonary valve replacement was 20.8 ± 9.1 years. Bioprosthetic valves were used for all the pulmonary valve replacements, and there were no mortalities. Patients who have undergone previous PA manipulation, regardless whether congenital pulmonary pathology is present, may be at risk for pulmonary valve replacement in adulthood. This report describes five cases of patients with a history of congenital heart surgery but no congenital pulmonary valve pathology who required pulmonary valve replacement due to the consequences of prolonged pulmonary regurgitation. Although pulmonary regurgitation may be well tolerated for many years, it is further evidence for the importance of close follow-up assessment and monitoring of young adults with congenital heart disease.     

Congenital Hypothyroidism

Availability of sensitive radioimunoassays for T₄ and TSH has simplified the detection and treatment of congenital hypothyroidism. Early diagnosis by newborn screening and prompt treatment should minimize the serious complications of mental retardation. Absence of clear cut signs and symptoms early in the life requires laboratory testing for early diagnosis. The high cost effectiveness of the screening programme has resulted in the implementation of mass screening in many countries. Several studies indicate a favourable IQ with initiation of treatment before the age of 3 months. Neonatal laboratory screening programs have made it possible to initiate treatment before one month of age. This may further improve the outcome of this common cause of preventable mental retardation.     

Incidence and Etiology of Mental Retardation in Patients with Congenital Heart Disease

Of 1,235 patients (609 male; 626 female) with congenital heart disease for whom types, etiology and associated congenital anomalies were determinable, 129 patients (10.4%) had mental retardatin. Patients with congenital heart disease complicated by mental retardation included 70 (54.3%) with chromosome aberrations, three(2.3%) with single gene disorders, two (1.6%) caused by environmental insult, and two (1.6%) with other recognized syndromes. Among the remaining 52 patients, asphyxia at birt was noted in 16, including 12 complicated by multiple malformations, and 4 in whom mental retardedation was presumed to be due to the asphyxia. In the remaining 36 patients, the incidence of the complication of mental retardation in cyanotic congenital heart disese was significantly higher than that in acyanotic congenital heart disease was signicantly higher than that in acyanotic congenital heart disease. Patients with congenital heart disease of unknown etiology associated with mental retardation included those from two families considered to have new pedigree syndromes.     

Repolarization Patterns in Congenital Heart Disease

The aim of this study was to study the repolarization patterns in pediatric patients with cyanotic and acyanotic congenital heart diseases as prolonged QT indicates a myocardium at risk of ventricular arrhythmia. A cross-sectional case–control study included 50 patients with acyanotic congenital heart diseases and 50 patients with cyanotic congenital heart diseases who presented to Catheterization Unit of Cairo University Pediatric Hospital between March 2013 and June 2014. We included 50 healthy children as a control. For all the patients’ measurement of oxygen saturation, echocardiography and 12-lead electrocardiogram (ECG) were done and the corrected QT (QTc) was measured. The mean QTc was significantly higher in acyanotic congenital heart diseases with volume overload than in control: 0.426 versus 0.4 s (p = 0.009). Increased left ventricular end-diastolic dimension was significantly associated with QTc prolongation (p = 0.01). Early repolarization was higher in congenital heart diseases (18 % in acyanotic patient, 48 % in cyanotic patients) than in control 6 %. Decreased oxygen saturation was significantly associated with early repolarization (p = 0.01). Prolonged QTc was higher in acyanotic congenital heart diseases with volume overload and increased left ventricular end diastolic dimension was a significant association. Decreased oxygen saturation was a significant association.     

Postoperative Use of Oral Sildenafil in Pediatric Patients with Congenital Heart Disease

We sought to determine the efficacy of postoperative oral sildenafil therapy (OST) in pediatric patients with congenital heart disease (CHD). A retrospective review of 45 postoperative patients with CHD who received OST was performed. Patients were categorized into three groups according to clinical indications: (1) to stabilize pulmonary vascular reactivity after biventricular repair (group 1 [n = 15]), (2) to lower pulmonary vascular resistance after bidirectional cavopulmonary shunt (group 2 [n = 12]), and (3) to improve post-Fontan hemodynamics (group 3 [n = 18]). Thirty-four patients (34 of 45 [75.6%]) had received inhaled nitric oxide (iNO) while on OST. Mean pulmonary arterial pressure (mPAP), mean systemic blood pressure (mSBP), and peripheral oxygen saturation (SpO₂) were recorded during the first 24 hours after the initiation of OST. In group 1, the baseline mPAP/mSBP ratio (0.60 ± 0.17) decreased significantly after the second (0.46 ± 0.14, p = 0.004) and fourth (0.50 ± 0.18, p = 0.025) doses of OST. In group 2, baseline SpO₂ (71.0 ± 12.3%) increased after the fourth dose (75.1 ± 12.3%, p = 0.04) of OST, without significant changes in mPAP. In group 3, baseline mPAP (14.8 ± 3.3 mmHg) decreased significantly after the first (13.9 ± 2.8 mmHg, p = 0.025) and second (13.3 ± 1.9 mmHg, p = 0.016) doses of OST, without changes in SpO₂. In thirty-one (31 of 34 [92%]) subjects, iNO was discontinued within a median of 2 days after the initiation of OST, without rebound phenomena. There were no OST-related complications. Sildenafil citrate can be used safely in postoperative pediatric patients with CHD. Benefits from OST may be manifested differently in various clinical settings.     

Imaging Modalities in Congenital Heart Disease

Indian Journal of Pediatrics - Cardiac imaging provides invaluable guidance at all stages of the management of congenital heart disease. Advances in the field of cardiac imaging have contributed...     

Prevalence of Obesity Among Patients With Congenital and Acquired Heart Disease

Overweight and obesity rates have risen dramatically in the United States, with subsequent detrimental comorbidity risks. The rates for obesity among children with congenital and acquired heart disease have rarely been reported. A retrospective cross-sectional study was conducted to determine the prevalence of overweight and obesity in children with heart disease and to identify subgroups at increased risk. A total of 795 cases were identified from a chart review of patients presenting to an urban center’s Pediatric Cardiology Program between 1 January and 31 December 2006. A body mass index (BMI) at the 85th percentile or higher was defined as overweight, and a BMI at the 95th percentile or higher was defined as obese. Subjects with comorbidities affecting body habitus were excluded from the study. Overall, overweight and obesity rates were similar to national data. No significant differences in overweight or obesity rates were detected between heart disease and non-heart disease groups (P = 0.50). According to multivariate analysis, Hispanic ethnicity and male gender were the only predictors of obesity. This study shows that children with heart disease are not immune to the common predictors of obesity such as gender and ethnicity and that the future care of children with heart disease should include general discussions about the risks for obesity.