Forms Of Single Ventricle Research Articles

Major Aortopulmonary Collateral Arteries With Anatomy Other Than Pulmonary Atresia/Ventricular Septal Defect

Major aortopulmonary collateral arteries (MAPCAs) are frequently found in association with pulmonary atresia with ventricular septal defect (PA/VSD). However, some patients with MAPCAs do not have PA/VSD but have a variety of other "atypical" anatomic diagnoses. This was a retrospective review of patients with MAPCAs and atypical anatomy. The 50 patients with MAPCAs could be divided into two subgroups: (1) single ventricle anatomy (n= 33) and (2) two ventricle anatomy (n= 17). The 33 patients with MAPCAs and single ventricle included 15 with unbalanced complete atrioventricular canal (CAVC), 6 with pulmonary atresia-intact ventricular septum, and 12 with other forms of single ventricle. The initial cardiac operation included unifocalization/shunt in 24 patients and creation of aortopulmonary window or central shunt in 9 patients. There were seven operative and eight late deaths. Sixteen patients have had a bidirectional Glenn procedure and6 had a Fontan procedure. The 17 patients with MAPCAs and two ventricles included 5 with CAVC, 4 with corrected transposition, 3 with double outlet right ventricle, 3 with scimitar syndrome, and 2 with complex D-transposition. The initial cardiac operation included single-stage complete repair in 5 patients, unifocalization/shunt in 10 patients, and aortopulmonary window in 2 patients. There were two operative and two late deaths. Thirteen patients have achieved complete repair status. The data demonstrate the wide diversity of anatomy seen in patients with MAPCAs when evaluating diagnoses other than PA/VSD. Two-thirds of the patients had single ventricle and was associated with a relatively high mortality.

Neurodevelopmental outcomes in preschool survivors of the Fontan procedure

The study objectives were to compare the neurodevelopmental outcomes of preschool survivors of the Fontan procedure with those of children with congenital heart disease undergoing biventricular repair and to investigate predictors of neurodevelopmental outcome for those with single ventricle congenital heart disease, including hypoplastic left heart syndrome. Neurodevelopmental outcomes were assessed at 4 years of age, including cognition, visual-motor integration, behavior, social skills, and academic achievement. Unadjusted outcomes were compared between patients with biventricular circulation and patients with single ventricles. Predictors of neurodevelopmental outcome were assessed in the patients with single ventricles. Multiple covariate models were evaluated using patient-related, operative, and postoperative covariates. Neurodevelopmental evaluation was performed in 365 children, 112 after the Fontan procedure (hypoplastic left heart syndrome, n=91; other single ventricle, n=21) and 253 after biventricular repair. Compared with patients with biventricular circulation, patients with single ventricles performed worse in terms of processing speed, inattention, and impulsivity. Otherwise, there were no significant differences between the groups for any domain. There was a trend toward lower performance for patients with single ventricles on visual motor integration. Outcomes for patients with hypoplastic left heart syndrome were not worse than for other forms of functional single ventricle. Patient factors were more important predictors of neurodevelopmental outcomes than were operative management variables. In this cohort, unadjusted neurodevelopmental outcomes for preschool survivors of the Fontan procedure are similar to those for children with congenital heart disease undergoing biventricular repair for most domains. Among the patients undergoing the Fontan procedure, hypoplastic left heart syndrome was not associated with worse outcomes compared with other forms of single ventricle.

Hyperglycaemia after Stage I palliation does not adversely affect neurodevelopmental outcome at 1 year of age in patients with single-ventricle physiology☆☆☆

Hyperglycaemia has been associated with worse outcome following traumatic brain injury and cardiac surgery in adults. We have previously reported no relationship between early postoperative hyperglycaemia and worse neurodevelopmental outcome at 1 year following biventricular repair of congenital heart disease. It is not known if postoperative hyperglycaemia results in worse neurodevelopmental outcome after infant cardiac surgery for single-ventricle lesions. Secondary analysis of postoperative glucose levels in infants <6 months of age undergoing Stage I palliation for various forms of single ventricle with arch obstruction. The patients were enrolled in a prospective study of genetic polymorphisms and neurodevelopmental outcomes assessed at 1 year of age with the Bayley Scales of Infant Development-II yielding two indices: mental developmental index (MDI) and psychomotor developmental index (PDI). Stage I palliation was performed on 162 infants with 13 hospital and 15 late deaths (17.3% 1-year mortality). Neurodevelopmental evaluation was performed in 89 of 134 (66.4%) survivors. Glucose levels at admission to the cardiac intensive care unit and during the first 48 postoperative hours were available for 85 of 89 (96%) patients. Mean admission glucose value was 274+/-91 mg dl(-1); the maximum was 291+/-90 mg dl(-1), with 69 of 85 (81%) patients having at least one glucose value >200 mg dl(-1). Only two patients had a value <50 mg dl(-1). Mean MDI and PDI scores were 88+/-16 and 71+/-18, respectively. There were no statistically significant correlations between initial, mean, minimum or maximum glucose measurements and MDI or PDI scores. Only delayed sternal closure resulted in a statistically significant relationship between initial, minimum and maximum glucose values within the context of a multivariate analysis of variance model. Hyperglycaemia following Stage I palliation in the neonatal period was not associated with lower MDI or PDI scores at 1 year of age.

Presentation of Congenital Heart Disease in the Neonate and Young Infant

Presentation of Congenital Heart Disease in the Neonate and Young Infant

Arrhythmias in Adult Patients With Congenital Heart Disease

By the time patients with congenital heart disease (CHD) reach adolescence and early adulthood, rhythm status has often become an active issue, if not the central issue, in their cardiac management. For some, arrhythmias are intrinsic to the structural malformation itself, as is the case with Wolff-Parkinson-White syndrome in the setting of Ebstein’s anomaly, or atrioventricular (AV) block in the setting of “congenitally corrected” transposition of the great arteries (L-TGA). For most other CHD patients, arrhythmias represent an acquired condition related to the unique myocardial substrate created by surgical scars in conjunction with cyanosis and abnormal pressure/volume loads of long duration. This review will attempt to address the major rhythm difficulties faced by adults with CHD, concentrating on electrophysiological features that distinguish CHD from more conventional forms of adult heart disease. A listing of specific arrhythmias and commonly associated congenital defects is provided in Table 1 to serve as an outline for the discussion. View this table: TABLE 1. Specific Arrhythmias and Associated Defects in Adults With Congenital Heart Disease As of 2001, there were estimated to be 800 000 adults with CHD living in the United States,1 a number that has grown steadily as more survivors of childhood surgery reach maturity. Of these, roughly 45% are considered to have mild forms of CHD (eg, atrial septal defect, valvar pulmonary stenosis), 40% are classified as having moderate disease (eg, tetralogy of Fallot, Ebstein’s anomaly), and 15% are considered to have complex disease (eg, single ventricle, transposition of the great arteries). Although arrhythmias can develop within any of the 3 subgroups, the incidence is highest for patients in the moderate and severe categories. Tetralogy of Fallot is an instructive example of moderate CHD with a large arrhythmia burden. As many as one third of patients with repaired tetralogy develop symptomatic atrial tachycardias by …

Management of the postoperative Fontan patient

The purpose of the Fontan operation is to effectively normalize the circulation pathway in patients with a single ventricle. Pulmonary blood flow is established by a direct systemic venous connection to the pulmonary artery without an interposed ventricular chamber; the single ventricle provides systemic blood flow. The modern Fontan procedure consists of a direct superior vena cava to pulmonary artery anastomosis with the inferior vena cava blood reaching the pulmonary artery by means of an internal tunnel through the right atrium or an extra cardiac conduit from the inferior vena cava to the pulmonary artery. The Fontan operation is performed in patients from late infancy to adulthood, and is now one of the most common surgical procedures for congenital heart disease over the age of two years. Excellent palliation, and increased life expectancy is expected for most patients. However, over time, complications may occur and they require careful diagnostic evaluation and specific management. Some manifestations may appear in patients with any form of single ventricle, whereas others are specifically related to the morphology of the original single ventricle anatomy. Potential late complications include: obstruction in the systemic venous pathway, competitive pulmonary collateral blood flow, significant A–V valvar insufficiency, bulboventricular foramen obstruction, ventricular dysfunction, arrhythmia, protein losing enteropathy, and thromboembolism. This monograph addresses the clinical and laboratory assessment of patients who have had a Fontan operation, and discusses the various complications and management options.

732-2 Extra-cardiac Conduit Total Cavopulmonary Anastamosis: Early and Mid Term Results of Further Modification of Fontan Procedure

Lateral tunnel modification of Fontan procedure (LTF) is widely practiced based on the advantages of better hydrodynamics and fewer atrial complications. We have routinely employed extra-cardiac conduit Fontan (ECCF) because of the following potential advantages: 1) it avoids the atrium completely in the Fontan path, 2) it can be performed on a perfused beating heart without cross clamping the aorta thereby completely avoiding ischemic insult to the myocardium, and 3) it provides improved laminar flow. From 7/92 to 8/94, 35 patients (pts) aged 1.7 to 44.2 years (median 6.52 years) underwent ECCF, including revision of a failing Fontan to ECCF in 7 pts. Principal diagnoses were tricuspid atresia (n: 14), double inlet ventricle (n: 10), corrected transposition of the great arteries (SLL) with left atrioventricular valve atresia (n:4) and other forms of single ventricle in the rest (n:7). An avenge of 2.3 previous operations were done per patient. Surgical procedure included extracardiac total cavopulmonary anastomosis using a ePTFE conduit (16 to 22 mm) or a nonvalved aortic homograft conduit (18 to 25 mm). Pop off fenestration between the conduit and the atrium was provided by a 4 - 5 mm ePTFE tube graft (n:20) or a side to side anastomosis with the atrium In:4). Additional surgical procedures included ligation of systemic shunts (n: 17), pulmonary arterioplasty (n:15), enlargement of bulboventricular foramen (n:4), mitral valve repair (n:1), and cryoablation of junctional ectopic focus (n:1). The only early death in the series was a pt of a failing Fontan with chronic massive ascites, pleural effusions, and cachexia who was not a candidate for heart transplant due to social reasons. Early complications included prolonged pleural and/or pericardial effusion in 6/34 pts (18%) and transient arrythmias in 6 pts. Permanent pacemaker was implanted in 4 pts: 2 pts with pre-existing CHB and 1 pt following VSD enlargement and 1 pt with SLL. At a folloW-up of 1 to 22 months (median 11) there were no significant new arrythmias, one pt required reoperation for thrombosis of left pulmonary artery and 3 pts required pericardioperitoneal window for effusion, and one pt died following re-do sternotomy. ECCF is an excellent alternative to LTF with good early and midterm results. However, late follow up is essential to evaluate its potential advantages.

Early and intermediate results of the fontan procedure at moderately high altitude

At higher elevations, alveolar hypoxia increases pulmonary vascular resistance and may limit the cardiac output of individuals without a subpulmonary ventricle. Thus, we reviewed the outcome of definitive palliation for tricuspid atresia and other forms of single ventricle in 60 consecutive Fontan patients living at a mean elevation of 1,370 m (range, 910 to 2,130 m). There were four early deaths (6.7%; 70% confidence limits, 4.1% to 10.7%) and six late deaths. Kaplan-Meier actuarial survival (± standard error) is 79.6% ± 8.2% at 5 years. Survival was significantly decreased in patients with a preoperative mean pulmonary arterial pressure greater than or equal to 15 mm Hg unless the Fontan procedure was performed with a residual fenestrarion. Exercise tolerance was significantly worse at higher elevations in a subgroup of patients who have traveled to altitudes of 1,680 to 3,350 m. We conclude that the early and intermediate results of the Fontan procedure at moderately high altitude are similar to results reported at sea level. However, exercise tolerance may be impaired at higher elevations in many patients.

Intermediate procedures after first-stage norwood operation facilitate subsequent repair

Actuarial analysis of survival after first-stage palliative reconstructive operation for hypoplastic left heart syndrome has revealed a high out-of-hospital attrition rate over the first 18 months to 2 years postoperatively. Some of this mortality is related to development of anatomical problems such as restrictive atrial septal defect, neoaortic arch obstruction, and pulmonary artery distortion. The bidirectional Glenn shunt has proved to be an ideal adjunctive procedure for high-risk patients at the time of operation to correct such intermediate-term problems. The fenestrated Fontan procedure, which involves fenestration of the interatrial baffle placed as part of our current standard Fontan procedure, is applied for patients considered to be at moderate risk for a Fontan procedure. The decision regarding closure of the fenestration is made by hemodynamic study including temporary balloon occlusion of the fenestration. The fenestration is closed with the double-clamshell device, which is placed percutaneously in the catheterization laboratory and which is currently used for secundum atrial septal defect closure. Appropriate selection of patients for the bidirectional Glenn shunt or fenestrated Fontan procedure with or without fenestration closure has resulted in a dramatic decrease in mortality and morbidity for patients with all forms of single ventricle and for patients with hypoplastic left heart syndrome.

Pediatric cardiac surgery.

The treatment of many forms of congenital heart disease has continued to advance, and numerous reports have appeared in the last year to document these improvements. Increased information regarding the "natural history" of repaired congenital heart disease has also been reported. Based both on improving results of surgical treatment and on the problems with delayed reparative operations, there has been continued interest in primary early repair of an increasing number of defects, including atrioventricular canal, tetralogy of Fallot, pulmonary atresia with intact ventricular septum, transposition of the great arteries, and truncus arteriosus. Advances have also been reported in transplantation for complex congenital heart disease and in the "physiologic correction" of various forms of single ventricle by the Fontan approach. A number of experimental reports on the protection of both the heart and the brain during ischemia point out areas where knowledge is incomplete and where further research is needed. These developments suggest that the overall outlook for the patient with congenital heart disease has continued to improve.

Modified Fontan procedure: atrial baffle and systemic venous to pulmonary artery anastomotic techniques.

Two technical modifications to the modified Fontan procedure are presented. Systemic venous to pulmonary artery continuity is achieved by superior vena cava (SVC) division and end to side anastomosis to the right pulmonary artery (RPA), particularly following a right Blalock shunt, or by RPA division and anastomosis to the SVC, particularly in the presence of RPA stenosis. Intra-atrial partitioning is achieved by a systemic venous baffle rather than a pulmonary venous baffle. This is particularly useful in the presence of left atrioventricular valve atresia, but may be a preferable technique with double-inlet single ventricle or single ventricle with common AV valve. These techniques were applied successfully to 10 of 12 children with various forms of single ventricle, including 5 with left AV valve atresia or stenosis.

Single Ventricle (Single- or Double-Inlet) Complicated by Subaortic Stenosis: Surgical Options in Infancy

Intracardiac obstruction to the systemic circulation can develop in patients with many forms of congenital heart disease. When transposition of the great arteries accompanies tricuspid atresia, narrowing of the ventricular septal defect (VSD) leads to subaortic stenosis. In a similar fashion, a restrictive bulboventricular foramen compromises systemic arterial outflow in patients who have single left ventricle with subaortic outflow chamber. The same effect can be seen in VSD closure in mitral atresia with normally related great vessels. Although some forms of single ventricle can be treated by ventricular septation, the modified Fontan procedure can be more generally applied to this entity. Pulmonary vascular resistance must be low, however, which excludes the application of the Fontan principle in infants. While pulmonary artery banding may protect the lungs from the development of excessive pulmonary vascular resistance, it may also accelerate the development of subaortic obstruction. We have successfully applied the Norwood operation, as described for hypoplastic left heart syndrome, to palliate subaortic stenosis due to restrictive VSD in 3 infants with single ventricle or atrioventricular valve atresia. Consideration should be given to a primary Norwood procedure in infants with single ventricle in whom subaortic stenosis is likely to develop. Patients who do receive pulmonary artery bands should be followed closely for the development of subaortic stenosis and should undergo an early, physiologically corrective operation if it occurs.