Transposition of the great arteries

Many patients with ventriculoarterial discordance have survived to adulthood. Those with complete transposition of the great arteries have often had an atrial switch procedure (Mustard or Senning operation) performed, which leaves the morphological right ventricle supporting the systemic circulation. It has been also reported previously undiagnosed congenitally corrected transposition of the great arteries. We present the complete transposition of the great arteries in an 8-year-old Romanian child with a septal defect of the ventricle (functionally single ventricle).     

Congenitally corrected transposition of the great arteries: Current treatment options

Opinion statement Congenitally corrected transposition of the great arteries is a relatively rare cardiac malformation characterized by atrioventricular and ventriculoarterial discordance. This double discordance results in a physiologically corrected circulation with the morphologic right ventricle (RV) serving as the systemic pump. Associated anomalies are present in approximately 98% of cases and include most commonly ventricular septal defect, pulmonary stenosis, and anomalies of the systemic atrioventricular valve (SAVV). Conduction abnormalities are common as well, predisposing these patients to the development of complete heart block. The management of these patients is primarily determined by the presence and severity of the associated anomalies. Conventional repair, which leaves the morphologic RV as the systemic ventricle, has resulted in high incidence of tricuspid regurgitation (TR) and progressive dysfunction of the RV. In the majority of patients, congestive heart failure secondary to RV dysfunction occurs by the fifth or sixth decade. The cause and effect relationship between TR and RV dysfunction remains to be determined. The advent of the Double Switch operation, which restores the morphologic left ventricle (LV) as the systemic ventricle, has yielded favorable outcomes at early follow-up. This procedure should be applied in young patients to achieve optimal results. Retraining the LV by pulmonary artery banding is associated with high morbidity and mortality when attempted after infancy or early childhood. Long-term follow-up is needed to evaluate the potential superiority of this procedure and the incidence of rhythm, baffle, and conduit complications for this management option.     

A case series of systemic right ventricular dysfunction post atrial switch for simple D-transposition of the great arteries: the impact of beta-blockade

BACKGROUND: Patients with atrial switch (Mustard or Senning) repair of D-transposition of the great arteries (D-TGA) are at increased risk for atrial arrhythmias, systemic right ventricular (RV) dysfunction and late mortality. OBJECTIVES: To evaluate case series from a single-centre experience with beta-blocker use in adult, post atrial switch, simple D-TGA patients. METHODS: The Adult Congenital Heart Disease Clinic (Halifax, Nova Scotia) database was used to identify patients with post atrial switch, simple D-TGA. Treatment effect of beta-blockade was evaluated. RESULTS: Eight patients were treated with beta-blockers for systemic RV dysfunction (n=2), arrhythmia (n=2) or both (n=4). Median follow-up was three years, at which time seven of eight patients were still on beta-blockade. Of those patients with complete data, two of five had improved systemic ventricular dysfunction, two of four had improved tricuspid regurgitation and four of six had improved functional capacity, as determined by history or exercise testing. Beta-blockade was well tolerated in seven of eight patients without any significant clinical deterioration. CONCLUSIONS: Beta-blockade was used infrequently in patients with a prior Mustard procedure. When beta-blockade was prescribed to patients with a prior atrial switch procedure, the drugs were well tolerated and were associated with trends toward improved symptoms, less tricuspid regurgitation and improved functional status in patients with reduced systemic RV function. These data support the need for a randomized trial of beta-blockade in patients with a previous Mustard or Senning operation and RV dysfunction.     

40 years after the first atrial switch procedure in patients with transposition of the great arteries: long-term results in Toronto and Zurich

The atrial switch procedure dramatically improved the prognosis of children with complete transposition of the great arteries (TGA). Overall actuarial survival was approximately 75% after 25 years and was better in patients with simple TGA than in those with complex TGA. Mortality by any cause (16%) and cardiovascular mortality (12% and 13%) were comparable in both centers. Progressive congestive heart failure and sudden death were the principal modes of death. Most of the survivors denied any symptoms or had mild limitations in their daily activities. However, long-term problems in this growing population of adults are challenging and include late arrhythmias (up to two thirds of the patients), systemic ventricular (SV) failure, systemic atrioventricular valve regurgitation and reoperations, such as baffle reconstruction, being the most frequent. Objective assessment of SV function obtained by echocardiography is difficult. It may include fractional area change and tricuspid annular motion. Survivors after an atrial switch procedure are unique and have a good quality of life. However, the definitive and true history of the RV supporting the systemic circulation is not as yet known.     

Left ventricular function in adult patients after the atrial switch operation for transposition of the great arteries

OBJECTIVES: Right ventricular function may deteriorate after the atrial switch operation in patients with transposition of the great arteries, but the effect on left ventricular function is unknown. Chronic left ventricular function was evaluated in adult patients after the atrial switch operation for transposition of the great arteries. METHODS: Right and left ventricular functions were evaluated using data from cardiac catheterization performed in nine patients older than 17 years who had undergone the atrial switch operation for transposition of the great arteries. The mean age at operation was 19 +/- 16 months and the age at catheterization ranged from 17 to 32 years (mean age 23 +/- 5 years). Echocardiography was performed in all patients to evaluate tricuspid regurgitation. Myocardial perfusion studies using technetium-99 m-tetrofosmin were assessed in five patients. RESULTS: Mean right ventricular end-diastolic volume was slightly increased to 122 +/- 27% of the normal value and mean right ventricular ejection fraction was depressed to 44 +/- 5% of the normal value. Left ventricular ejection fraction ranged from 37% to 63% (mean 50 +/- 7%) and was under 50% in four of the nine (44%) patients. Right ventricular ejection fraction was positively correlated with left ventricular ejection fraction(r = 0.72, p < 0.05). All patients had tricuspid regurgitation, mild in four, moderate in four, and severe in one patient. Left ventricular ejection fraction was lower in patients with moderate or severe tricuspid regurgitation(54 +/- 4%) than in patients with mild tricuspid regurgitation(47 +/- 6%, p < 0.05). Mild or moderate perfusion abnormalities were observed in all patients (five of five) who underwent myocardial perfusion studies. Mean right and left ventricular ejection fractions were 43 +/- 3% and 50 +/- 3%, respectively, in patients who underwent myocardial perfusion study, which were under the normal levels. CONCLUSIONS: Left ventricular dysfunction is common in adult patients after the atrial switch operation for transposition of the great arteries. Some right ventricular abnormalities may correlate with the left ventricular dysfunction.     

Congenital heart disease in adults: residua,sequelae, and complications of cardiac defects repaired at an early age

Nowadays, it is estimated that 85% of the infants born with congenital heart disease (CHD) will survive to adulthood, thanks mainly to surgical or therapeutic procedures performed during infancy or childhood. The clinical profile and disease pattern of adults with CHD is changing. The prevalence of certain adult CHDs, such as tetralogy of Fallot, transposition of the great arteries or univentricular heart, is rising, but these conditions have practically become new diseases as a result of therapy. Most surviving patients present residua, sequelae, or complications, which can progress during adult life. These disorders can present electrophysiological disturbances, valvular disease, persistent shunts, myocardial dysfunction, pulmonary or systemic vascular disease, problems caused by prosthetic materials, infectious complications, thromboembolic events, or extravascular disorders involving multiple organs or systems. In tetralogy of Fallot, the most striking problems that affect long-term prognosis are pulmonary valve regurgitation, right ventricle dysfunction, and atrial or ventricular arrhythmias. The main problems appearing after physiological atrial repair of transposition of the great arteries are related to right ventricular function, since it is structurally unprepared for systemic circulation, and atrial arrhythmias. Surgical repair of univentricular heart using Fontan techniques should be considered a palliative procedure that does not modify the underlying structural disorder and exposes the postoperative patient to severe complications and problems. The increase in the number of patients with CHD who will reach adulthood in the coming decades makes it necessary to carefully consider the new healthcare demands that are being generated, who should be responsible for them, and how and where solutions can be found.     

Congenitally corrected transposition of the great arteries: An update

Opinion statement  Congenitally corrected transposition of the great arteries is a rare condition in which systemic venous blood returns to normally positioned atria. However, the atria are connected to the opposite ventricle, right atrium to left ventricle, left atrium to right ventricle; so-called atrioventricular disordance. In addition, the ventricles are inverted (right to left change in position) and are connected to the opposite great artery, left ventricle to pulmonary artery, right ventricle to aorta; thus, forming ventricular-arterial discordance. The aorta is anterior and to the left of the pulmonary artery, L-transposed. Atrioventricular discordance plus ventricular-arterial discordance results in normal blood flow (ie, congenitally corrected). The right ventricle with the tricuspid valve is the systemic ventricle. Common associated conditions are ventricular septal defects (VSDs), pulmonary stenosis, and congenital heart block. Major issues related to management revolve around the status of the systemic right ventricle, which can develop dysfunction with increasing age and tricuspid regurgitation, which can increase in severity with age and contribute to ventricular dysfunction. One emerging treatment is the double switch operation. In patients with no pulmonary obstruction, it is possible to switch the systemic and pulmonary venous return using an atrial baffle procedure followed by an arterial switch procedure. This results in the anatomical left ventricle now functioning as the systemic ventricle. In those patients with associated pulmonary obstruction and a VSD, another type of double switch can be performed in which the left ventricle is tunneled through the VSD to the aorta, the right ventricle is connected to the pulmonary artery with a homograft or other conduit, and the atrial baffle procedure is performed. The most difficult challenge is choosing the patient who is a candidate for the double-switch operation and the timing of that operation, or the timing of a more classical operation for associated defects.     

Non-surgical ablation of the ventricular septum for the treatment of hypertrophic cardiomyopathy.

OBJECTIVES--A combined atrial and arterial switch procedure was performed in selected patients with congenitally corrected transposition to establish the morphological left ventricle as the systemic ventricle. Immediate and early follow up results are presented. BACKGROUND--Progressive right ventricular dysfunction and tricuspid regurgitation are common in patients with congenitally corrected transposition who undergo repair of associated lesions. A surgical procedure which re-establishes the left ventricle as the systemic ventricle should improve functional results. METHODS--Four symptomatic children aged from 9 months to 3 years 1 month (mean 2 years 3 months) with congenitally corrected transposition and ventricular septal defect underwent both an atrial and arterial switch procedure and were followed up for a mean of 12 months (range 6-21 months). RESULTS--There were no early or late deaths. Conduction abnormalities worsened in two patients. Hospital stay ranged from 8 to 17 days (mean 13 days). The cardiothoracic ratio decreased from a mean (range) of 0.65 (0.6 to 0.71) to 0.58 (0.52 to 0.6). Currently, three patients are in functional class I and one child is in functional class II. CONCLUSIONS--The combination of an atrial and an arterial switch procedure in symptomatic children with congenitally corrected transposition establishes the left ventricle as the systemic ventricle. The initial experience is encouraging with excellent immediate and early follow up results.     

Maintaining tricuspid valve competence in double discordance: a challenge for the paediatric cardiologist

Objectives—To establish the prevalence of tricuspid valve abnormalities in children with a double discordant heart (or congenitally corrected transposition of the great arteries); to study the influence of the loading conditions induced by various surgical interventions on the right and left ventricle in patients with double discordance and an abnormal tricuspid valve; and to propose a rational surgical approach.
Methods—Case notes were reviewed of 141 consecutive patients admitted in the first year of life with various types of double discordance (intact ventricular septum (group 1), ventricular septal defect (group 2), ventricular septal defect and pulmonary obstruction (group 3)). A study group of 62 patients with an abnormal tricuspid valve was selected by cross sectional echocardiography. These were followed up through palliative and open heart procedures with grading of tricuspid regurgitation.
Results—Tricuspid valve abnormalities were more common in groups 1 and 2 (60% and 56%) than in group 3 (31%). Preoperative tricuspid regurgitation was more common in group 2 (90%) than in groups 1 and 3 (38% and 36%). Ten patients in groups 1 and 2 died in the neonatal period with severe tricuspid regurgitation, associated with coarctation of the aorta in 60%. Eight patients in group 1 had no surgery and are doing well, with a competent tricuspid valve. Palliative procedures were undertaken in 28 patients: 14 had pulmonary artery banding, which resulted in a decrease in tricuspid regurgitation, 12 in group 2 by reducing the pulmonary blood flow and two in group 1 by changing the septal geometry; 14 in group 3 had an aortopulmonary shunt, which induced tricuspid regurgitation in two. Twenty patients are still alive after palliation, with stable tricuspid valve function. Repair of the tricuspid valve was unsuccessful in the three patients who underwent conventional surgery, leaving the right ventricle facing the systemic circulation. In two patients with a competent but abnormal tricuspid valve, conventional surgery induced severe tricuspid regurgitation. Of the 15 patients who underwent conventional surgery, only 10 survived (mortality 33%): eight with a tricuspid valve prosthesis and two with severe residual tricuspid regurgitation. However, tricuspid regurgitation decreased after anatomical correction (nine patients), restoring a systemic left ventricle and a subpulmonary right ventricle, even when the tricuspid valve was not repaired (five patients). Eight patients are doing well after anatomical correction (mortality 11%).
Conclusions—Tricuspid valve function in double discordance with an abnormal tricuspid valve depends on the loading conditions of both ventricles and on the septal geometry. Interventions that increase right ventricular volume or decrease left ventricular pressure are likely to induce tricuspid regurgitation, while those that decrease right ventricular volume or increase left ventricular pressure are likely to improve tricuspid valve function. Repair of the tricuspid valve always failed when the right ventricle was left in a systemic position and always succeeded when the right ventricle was placed in a subpulmonary position. These results should be taken in to account when dealing with patients with double discordance and an abnormal tricuspid valve.

Keywords: transposition of the great arteries;  double discordance;  double switch procedures;  tricuspid valve;  paediatric cardiology;  congenitally corrected transposition     

Evaluation and management of the adult patient with transposition of the great arteries following atrial-level (Senning or Mustard) repair

Atrial-level repair for transposition of the great arteries is one of the greatest achievements of modern cardiovascular medicine, transforming a once fatal congenital heart condition into one with excellent long-term survival. Although atrial-level repair has been supplanted by the arterial switch, there remains a population of patients who underwent atrial-level repair as children and now require ongoing care as adults. Survival slowly continues to decline in this population mainly owing to systemic right ventricular dysfunction and sudden death. Other problems include sinus node dysfunction, atrial arrhythmias, systemic atrioventricular valve regurgitation, baffle problems, and pulmonary hypertension. Evaluation and management of these late complications is addressed.     

Long-term outcome in congenitally corrected transposition of the great arteries: a multi-institutional study

OBJECTIVES: The purpose of this study was to determine long-term outcome in adults with congenitally corrected transposition of the great arteries (CCTGA), with particular emphasis on systemic ventricular dysfunction and congestive heart failure (CHF). BACKGROUND: Patients with CCTGA have the anatomical right ventricle as their systemic pumping chamber, with ventricular dysfunction and CHF being relatively common in older adults. METHODS: Retrospective analysis of records of 182 patients from 19 institutions were reviewed to determine current status and possible risk factors for systemic ventricular dysfunction and CHF. Factors considered included age, gender, associated cardiac defects, operative history, heart block, arrhythmias and tricuspid (i.e., systemic atrioventricular) regurgitation (TR). RESULTS: Both CHF and systemic ventricular dysfunction were common in groups with or without associated cardiac lesions. By age 45, 67% of patients with associated lesions had CHF, and 25% of patients without associated lesions had this complication. The rates of systemic ventricular dysfunction and CHF were higher with increasing age, the presence of significant associated cardiac lesions, history of arrhythmia, pacemaker implantation, prior surgery of any type, and particularly with tricuspid valvuloplasty or replacement. Aortic regurgitation (a previously unreported problem) was also relatively common in this patient population. CONCLUSIONS: Patients with CCTGA are increasingly subject to CHF with advancing age; this complication is extremely common by the fourth and fifth decades. Tricuspid (systemic atrioventricular) valvular regurgitation is strongly associated with RV (anatomical right ventricle connected to aorta in CCTGA patients; systemic ventricle in CCTGA) dysfunction and CHF; whether it is causative or a secondary complication remains speculative.     

Ebstein’s malformation

Opinion statement Ebstein’s malformation of the tricuspid valve is a complex and heterogeneous disorder that has diverse hemodynamic and arrhythmic manifestations. Hemodynamic dysfunction is due to valvar regurgitation and decreased pulmonary blood flow, varying in severity from mild tricuspid insufficiency to severe dysplasia of the right ventricle without forward flow. Atrioventricular reentrant tachycardia and atrial tachyarrhythmias are commonly associated with Ebstein’s malformation. Treatment ranges from conservative medical management to the ablation of pathways by catheterization to complex surgical repair or palliation. All patients with Ebstein’s malformation should be followed on a regular basis by a cardiologist familiar with congenital heart disease. The frequency of evaluations should depend on the severity of the disease and the presence of arrhythmias. A specialist in electrophysiology should also follow those patients with complex arrhythmias.     

Congenitally Corrected Transposition of the Great Arteries and Concomitant Coronary Artery and Valvular Disease in the Adult Patient

Congenitally corrected transposition of the great arteries (ccTGA) accounts for less that 1% of cardiac anomalies, and is defined as ventriculoarterial and atrioventricular (AV) discordance. The double discordant connection allows for survival with the right ventricle performing as the systemic ventricle, and the left ventricle as the pulmonary ventricle. We report a case of ccTGA in a 35-year-old male with situs inversus totalis status post repair of a ventricular septal defect (VSD) with a residual VSD, severe systemic AV valve regurgitation, and coronary artery disease who presented with chest pain. He subsequently underwent tricuspid valve replacement and VSD repair, followed by percutaneous coronary revascularization. This case highlights many important issues of adults with congenital cardiac disease, as well as the specific surgical management of anomalies associated with ccTGA. We review the literature and discuss the management of these complicated patients.     

Congenitally corrected transposition with mirror-image atrial arrangement

Congenitally corrected transposition (discordant atrioventricular and ventriculoarterial connexions) with mirror-image atrial arrangement is much less frequent than the same chamber combinations in the setting of usual atrial arrangement. This scarcity of cases has made their analysis difficult. In this study we have compared the anomalies found in 19 patients with congenitally corrected transposition in mirror-image arrangement with those in 39 patients having usual atrial arrangement. Absolute, relative and attributable risks were calculated for the presence of subvalvar pulmonary stenosis, ventricular septal defect, tricuspid regurgitation, atrioventricular block or the absence of these anomalies for each of the two groups. A greater absolute risk was found for both subvalvar pulmonary stenosis (68.4 vs. 43.6%, respectively) and ventricular septal defect (63.2 vs. 58.9%, respectively). The absolute risk for tricuspid regurgitation was 25.6% in those with usual arrangement as against 21.1% in those with mirror-image arrangement. Atrioventricular block was also more frequent in those with usual arrangement (25.6 vs. 10.5%) as was absence of associated cardiac defects (17.9 vs. 10.5%, respectively). The relative risks were greater for subvalvar pulmonary stenosis and ventricular septal defect in the patients with mirror-image as opposed to usual atrial arrangement (1.57: 1.00 and 1.07: 1.00, respectively), contrasting with greater relative risk for tricuspid regurgitation (1.26: 1.00), atrioventricular block (2.43: 1.00) and absence of associated anomalies (1.70: 1.00) in the patients with usual arrangement. The attributable risk for subvalvar pulmonary stenosis was estimated to be 24.8% and ventricular septal defect 4.3% for those having mirror-image atrial arrangement.(ABSTRACT TRUNCATED AT 250 WORDS)     

Congenitally corrected transposition of the great arteries with coexisting stenosis of pulmonary trunk valve and ventricular septum defect in a 55-year-old woman--a case report

Congenitally corrected transposition of the great arteries (CCTGA) is a rare cardiac malformation. This anomaly is characterised by atrioventricular as well as ventriculoarterial discordance. Isolated CCTGA may cause no symptoms until adult life. Most CCTGA cases with concomitant cardiac abnormalities are symptomatic and are therefore usually diagnosed in childhood. In the majority of patients, congestive heart failure secondary to right ventricular dysfunction occurring by the fifth or sixth decade enables diagnosis. We present an oligosymptomatic 55-year-old woman with corrected transposition of the great arteries and coexisting stenosis of pulmonary trunk valve and ventricular septum defect.     

Double outlet right ventricle with discordant atrioventricular connection. Clinical study

The clinical and anatomic findings were reviewed in 17 patients with double-outlet right ventricle and atrioventricular discordance. Ten cases had atrial situs solitus, seven with right-sided heart three with left-sided heart. Seven cases had atrial situs inversus, five with left-sided heart and two with right-sided heart. All cases presented ventricular septal defect, 13 subvalvar pulmonary stenosis, two tricuspid regurgitation and two complete atrioventricular block. The spatial relationship between the arterial valves are variable. Most cases in atrial situs solitus had a left-sided and anterior aorta and all patients in atrial situs inversus had a right-sided and anterior aorta. In this study we compared the anomalies found in our cases with double outlet right ventricle with those in 58 patients with corrected transposition. Absolute, relative and attributable risks were calculated for the presence of subvalvular pulmonary stenosis, ventricular septal defect, tricuspid regurgitation and atrioventricular block for each the two groups. We concluded that patients with double-outlet right ventricle are more prone to present ventricular septal defect and subvalvar pulmonary stenosis, while those with corrected transposition have a greater likelihood of presenting with tricuspid regurgitation and atrioventricular block. There is no typical clinical picture for the malformations. Symptoms depend upon the associated anomalies. The final diagnosis is best achieved by the echocardiographic and angiocardiographic studies, but electrocardiogram and chest radiograph may suggest the presence of a discordant atrioventricular connection.     

Atrioventricular discordance. Clinico-surgical experience 1990-2000

OBJECTIVE: To know the incidence of ventriculoarterial connections combined with atrioventricular discordance, associated lesions and surgical results, including the first case with anatomical correction. METHOD: All patients with atrioventricular discordance by echocardiography from 1990 to March 2000 were analyzed. RESULTS: Thirty six patients with atrioventricular discordance were found. Ages ranged from 0.1 to 46 years, with a mean 9.2 years (SD 5.9 years). Atrial chambers were situs solitus in 88.9%, inversus in 11.2%. The ventriculoarterial connections were discordant in 28 (77.7%), double outlet right ventricle in 4 (11.1%) (one of them was a "criss cross" heart), single outlet (pulmonary atresia) in 4 (11.1%), and double outlet left ventricle in 1 (2.7%). Associated lesions: Ventricular septal defect with pulmonary stenosis or atresia was present in 21 (58%), ventricular septal defect with no pulmonary obstruction was observed in 10 (28%). Five had tricuspid regurgitation with right ventricular disfunction, (two adults). Surgical results: 22 (61%) required 28 surgical procedures: 8 (36%) were palliative and 19 (86%) were corrective, one of them was our first anatomical correction. Operative mortality in all was 40.1%, postoperative atrioventricular block was observed in 9 (40.1%). CONCLUSION: Right ventricular dysfunction is not uncommon. Surgical results revealed high mortality and high pacemaker requirement for atrioventricular block.     

Medium-term outcome of anatomically repaired congenitally corrected transposition: the double switch operation

BACKGROUND: The double switch operation is emerging as the procedure of choice for congenitally corrected transposition of the great arteries. However, rhythm disturbances in the postoperative period are rarely discussed. METHODS AND RESULTS: Eighteen survivors who underwent corrective surgery for congenitally corrected transposition of the great arteries were followed up. Patients in group I (n=8), who also had a ventricular septal defect and pulmonary stenosis, had undergone the Senning plus Rastelli operation. Patients in group II (n=10), who did not have pulmonary stenosis, had undergone the Senning and arterial switch operation. The patients were followed up by periodical clinical examination, echocardiography and 24-hour Holter monitoring. In group I, follow-up ranged from 24 to 66 months (mean 44 months). There was no late death and all the patients are symptom free. There was no significant atrioventricular valve regurgitation and left ventricular function was normal. There were no rhythm disturbances. In group II, follow-up ranged from 2 to 72 months (mean 48 months). There were 2 late deaths due to atrial tachyarrhythmia and residual pulmonary hypertension 36 and 8 months after the procedure, respectively. One patient had significant mitral regurgitation and required mitral valve replacement. Three patients had recurrent atrial/junctional tachyarrhythmia: one of them was lost to follow-up after 1 year while another died of resistant atrial tachyarrhythmia. The third patient underwent mitral valve replacement for severe mitral regurgitation and developed complete heart block necessitating a permanent pacemaker implantation. CONCLUSIONS: Though good long-term results are obtained following the double switch operation, the problem of atrial arrhythmias still needs to be addressed suitably.     

Surgical closure of atrial septal defect before or after the age of 25 years. Comparison with the natural history of unoperated patients

INTRODUCTION: Surgical closure of an atrial septal defect (ASD) before the age of 25 years has been demonstrated to reduce complications during adulthood. However, the outcome for patients operated after the age of 25 is still debated. METHODS: In a retrospective study we examined the outcome of early and late surgical repair of ASD in adults, as compared with the natural evolution of unoperated patients. The study population was 280 patients (mean age 40 18 years) with non-restrictive ASD: 102 patients (group 1) underwent surgery before the age of 25 years, 90 patients (group 2) underwent surgery after the age of 25 years, and 88 unoperated patients were older than 25 years at the time of study (group 3). The variables analyzed were left ventricular systolic function, left atrial dimensions, systolic pulmonary pressure, right ventricular dimensions, the degree of mitral and tricuspid regurgitation, and the prevalence of late atrial fibrillation. RESULTS: Left ventricular systolic function and the degree of mitral regurgitation were not statistically different between groups. Compared with the patients in group 2, the patients in group 1 had a significantly lower systolic pulmonary arterial pressure (p < 0.001) and less dilated right ventricle (p < 0.001) and left atrium (p < 0.001). The degree of tricuspid regurgitation (p < 0.001) and prevalence of atrial fibrillation (p < 0.001) were significantly higher in the patients of group 2. Compared with group 3, the patients in group 2 had a significantly lower systolic pulmonary arterial pressure (p < 0.001) and less dilated right ventricle (p < 0.001). However, the left atrial dimensions, degree of tricuspid regurgitation, and prevalence of atrial fibrillation did not differ in a statistically significant way between the two groups. CONCLUSIONS: Surgical repair of an atrial septal defect in patients over 25 years of age does not fully prevent hemodynamic deterioration and the development of atrial arrhythmias. Therefore it seems that the surgical closure of ASD before adulthood should be strongly recommended.     

A new beginning: nursing care of the infant undergoing the arterial switch operation for transposition of the great arteries

Transposition of the great arteries is a common form of cyanotic congenital heart disease that without intervention has a 90% mortality rate within the first year of life. In the past, surgical options were limited to physiologic correction at the atrial level, but long-term follow-up has revealed problems with right ventricular dysfunction, tricuspid valve insufficiency, arrhythmias, and venous obstruction. This has renewed an interest in the arterial switch as an early, definitive form of anatomic correction for infants with transposition. As selection criteria have been refined, the mortality rate at experienced centers now equals that of physiologic correction. Nursing care centers around the critically ill neonate who may have hypotension and low cardiac output because of a poorly adapted left ventricle. Assessment for potential myocardial infarction resulting from movement and reimplantation of the coronary arteries is essential.