Rhythm and conduction disturbances in isolated, congenitally corrected transposition of the great arteries

Overview of Long-Term Outcome in Adults with Systemic Right Ventricle and Transposition of the Great Arteries: A Review

The population of patients with a systemic right ventricle (sRV) in biventricular circulation includes those who have undergone an atrial switch operation for destro-transposition of the great arteries (d-TGA) and those with congenitally corrected transposition of the great arteries (ccTGA). Despite the life expectancy of these patients is significantly increased, the long-term prognosis remains suboptimal due to late complications such as heart failure, arrhythmias, and premature death. These patients, therefore, need a close follow-up to early identify predictive factors of adverse outcomes and to implement all preventive therapeutic strategies. This review analyzes the late complications of adult patients with an sRV and TGA and clarifies which are risk factors for adverse prognosis and which are the therapeutic strategies that improve the long-term outcomes. For prognostic purposes, it is necessary to monitor sRV size and function, the tricuspid valve regurgitation, the functional class, the occurrence of syncope, the QRS duration, N-terminal pro B-type natriuretic peptide levels, and the development of arrhythmias. Furthermore, pregnancy should be discouraged in women with risk factors. Tricuspid valve replacement/repair, biventricular pacing, and implantable cardioverter defibrillator are the most important therapeutic strategies that have been shown, when used correctly, to improve long-term outcomes.

A new score for life-threatening ventricular arrhythmias and sudden cardiac death in adults with transposition of the great arteries and a systemic right ventricle

AIMS

To investigate the incidence of major adverse ventricular arrhythmias and related events (MAREs) and to develop a stratification tool predicting MAREs in adults with a systemic right ventricle (sRV).

METHODS AND RESULTS

In a multicentre approach, all adults (≥16 years old) with a sRV undergoing follow-up between 2000 and 2018 were identified. The incidence of MAREs, defined as sudden cardiac death, sustained ventricular tachycardia, and appropriate implantable cardioverter-defibrillator (ICD) therapy, was analysed. The association of MAREs with clinical, electrical, and echocardiographic parameters was evaluated. A total of 1184 patients (median age 27.1 years; interquartile range 19.9-34.9 years; 59% male; 70% with atrial switch repair for D-transposition of the great arteries) were included. The incidence of MAREs was 6.3 per 1000 patient-years. On multivariate analysis, age, history of heart failure, syncope, QRS duration, severe sRV dysfunction and at least moderate left ventricular outflow tract obstruction were retained in the final model with a C-index of 0.78 [95% confidence interval (CI) 0.72-0.83] and a calibration slope of 0.93 (95% CI 0.64-1.21). For every five ICDs implanted in patients with a 5-year MARE risk >10%, one patient may potentially be spared from a MARE.

CONCLUSION

Sudden cardiac death remains a devastating cause of death in a contemporary adult cohort with a sRV. A prediction model based on clinical, electrocardiographic, and echocardiographic parameters was devised to estimate MARE risk and to identify high-risk patients who may benefit from primary prevention ICD implantation.

Transvenous pacing through the pulmonary valve in a patient with cyanotic congenital heart disease after Glenn shunt - A case report

Bradyarrhythmia requiring pacing is infrequently encountered in patients with complex cyanotic congenital heart disease. Even though epicardial pacing is the preferred mode, rarely, a need for endocardial lead implantation arises. Patients with cavopulmonary shunts limit access to the venous atria and ventricles, necessitating alternate methods of pacemaker implantation. We report transvenous endocardial lead implantation by an unconventional method in a patient with congenitally corrected transposition of great arteries after a bidirectional Glenn shunt.

Association between reduced heart rate variability components and supraventricular tachyarrhythmias in patients with a systemic right ventricle

BACKGROUND

Patients with a systemic right ventricle are prone to develop heart failure. Abnormal heart rate variability (HRV), a measure of autonomic dysfunction, is associated with morbidity and mortality in patients with left ventricular failure. The association between HRV and supraventricular arrhythmias (SVTs), which are associated with adverse events in this population, was assessed.

METHODS

24-Hour Holter recordings of patients with a systemic right ventricle and healthy controls were analysed in a retrospective cohort study. HRV was calculated and compared between groups. Correlation coefficients were determined for HRV variables and clinical characteristics. The relation between HRV and SVTs was investigated with linear regression.

RESULTS

The patient group included 29 patients (69%) late after Mustard or Senning correction for transposition of the great arteries, and 13 patients with congenitally corrected transposition of the great arteries (31%). The control group included 38 subjects. HRV was significantly lower in patients compared with controls. In the patient group, lower SDANN (standard deviation of the average NN intervals calculated over 5-minute intervals) was independently associated with a higher number of supraventricular arrhythmias (95% CI -0.03 to -0.0004, p = 0.045). In exploratory correlation analysis, several HRV variables correlated with echocardiographic systemic right ventricular function (rho = 0.36, p = 0.02 for SDANN), and exercise capacity (rho = 0.39, p = 0.05 for SDANN).

CONCLUSION

In patients with a systemic right ventricle, HRV is lower compared with controls and (SDANN) is independently associated with supraventricular arrhythmias.

Congenitally Corrected Transposition of the Great Arteries in a Septuagenarian from the Developing Country of Pakistan

Congenitally corrected transposition of the great arteries (CCTGA) is a rare congenital cardiac defect with atrioventricular and ventriculoarterial discordance which leads to heart failure and limits patients’ lifespan. We report the case of a 70-year-old lady, from a poor province in Pakistan, who presented for the first time with palpitations and was diagnosed to have CCTGA. She had moderate pulmonic valve stenosis which was protective against heart failure. She had six children all born via spontaneous vertex delivery in her local village. This case exemplifies the fact that pulmonic stenosis is favourable for patients with CCTGA. In a country where the average life expectancy of females is only 68 years, the survival of our patient with CCTGA beyond the average lifespan is indeed interesting.

Late diagnosis of a congenitally corrected transposition of the great arteries discovered at pacemaker implantation in a patient previously diagnosed with dextrocardia and situs solitus

Congenitally corrected transposition of the great arteries (CCTGA) should not be missed in patients with dextrocardia and situs solitus. We report a case of a 56-year-old man with late diagnosis of CCTGA after ventricular lead replacement. Free LV wall pacing may be favorable in these patients so to prevent deterioration of the systemic RV function.

Rhythm disturbances and treatment strategies in children with congenitally corrected transposition of the great arteries

BACKGROUND

We aimed to evaluate rhythm abnormalities in cases of congenitally corrected transposition of the great arteries (ccTGA) and associated treatment strategies.

PATIENTS AND METHODS

This retrospective cohort study included 65 pediatric patients with ccTGA who were admitted to the clinic between 2009 and 2017. The patients were divided into two groups, and surgical data, Holter electrocardiographic (ECG) recordings, ECG recordings, electrophysiological data, and device implantation data on the two groups were compared.

RESULTS

Group I (n = 53, 82%) consisted of patients with significant associated lesions, and Group II (n = 12, 18%) consisted of those with minor or no associated lesions (isolated ccTGA). Rhythm abnormalities were diagnosed in 22 (34%) of the patients based on initial ECG findings and Holter ECG recordings. Eleven (17%) of these patients had atrioventricular (AV) block of different degrees, and the other 11 (17%) had supraventricular arrhythmia (SVA). The median follow-up was 49 months (range, 9-89 months), and the rhythm remained normal in 26 (42%) of the patients. Three patients died on follow-up. Of 40 patients with normal initial findings, nine required pacemaker implantation due to complete heart block, and SVA developed in seven patients on follow-up. No ventricular tachycardia was seen initially or on follow-up. Ablation was performed in four patients. During the follow-up period, pacemakers were implanted in 12 (23%) of patients in Group I and 4 (33%) of patients in Group II due to complete heart block. Cardiac resynchronization therapy (CRT) was performed in four patients due to systemic ventricular dysfunction. Notably, all four of these patients had a pacemaker implanted postoperatively.

Bradyarrhythmias in Congenital Heart Disease

Bradyarrhythmias in adults with congenital heart disease (CHD) comprise a complex group of arrhythmia disorders with congenital and acquired origins, highly variable long-term sequelae, and complicated treatment options. They can develop across the spectrum of CHD defects and can be encountered at all ages. Although permanent pacing is effective in treating bradyarrhythmias, it is associated with many complications and morbidity, where it is often used early in life. This section discusses the incidence and prevalence of bradyarrhythmias in the CHD population, their timing of occurrence with respect to specific disease entities and interventions, and their short- and long-term clinical sequelae.

Arrhythmias in adult congenital heart disease

Recent advances in pediatric cardiology and cardiac surgery have allowed a rapidly expanding population of patients with congenital heart disease to thrive well into their adult years. Often after prolonged uneventful clinical courses as children and adolescents, arrhythmias may surface later in life. These arrhythmias are a major source of morbidity. In addition, sudden death is the leading cause of mortality in adult patients with congenital heart disease. This review highlights the various types of brady- and tachyarrhythmias encountered in the more common forms of adult congenital heart disease and explores prognostic implications and therapeutic options.

Management of late arrhythmias in adults with repaired congenital heart disease

OPINION STATEMENT

As survival of patients with congenital heart disease improves with surgery and the population of patients with repaired adult congenital heart disease (ACHD) age, understanding complications such as arrhythmias has become more important. Arrhythmias account for significant morbidity and mortality in the ACHD population. Atrial arrhythmias occur in 15 % of patients with ACHD and, in patients with severe congenital heart disease (CHD), more than 50 % develop atrial arrhythmias by the age of 65 years [1]. This article aims to give an overview of arrhythmias seen in the ACHD population and the treatment modalities available now.

Comparison of outcomes in adults with congenitally corrected transposition with situs inversus versus situs solitus

The long-term outcome of patients with congenitally corrected transposition of the great arteries is mainly determined by progressive morphologically tricuspid valve regurgitation, heart block, atrial arrhythmias, and/or systemic ventricular dysfunction. Situs abnormalities have been reported in ≤34% of cases, but whether clinical differences exist between a situs inversus and situs solitus arrangement has not yet been studied. The clinical records of 38 adults with congenitally corrected transposition of the great arteries (mean age 40 ± 15 years) followed for a mean period of 7.4 years were reviewed. Of these 38 patients, 8 presented with situs inversus and 30 with situs solitus. No significant differences were found between the 2 groups in age, gender, ventricular septal defect, pulmonary tract stenosis, previous surgical repair, or duration of follow-up. However, none of the patients with situs inversus presented with an Ebstein-like anomaly of the morphologically tricuspid valve and none developed nonoperative-related complete atrioventricular block compared to 15 (50%; p = 0.013) and 11 (42%; p = 0.032) of the patients with situs solitus, respectively. At follow-up, 2 patients with situs inversus (25%) presented with sustained atrial arrhythmia, severe tricuspid regurgitation, or severe systemic right ventricular systolic dysfunction compared to 22 (73%) of 30 those with situs solitus (p = 0.034). No patient with situs inversus presented with cardiac death or severe heart failure compared to 12 (40%) of 30 with situs solitus (p = 0.038). In conclusion, Ebstein-like anomaly or spontaneous complete atrioventricular block are rare in patients with congenitally corrected transposition of the great arteries with situs inversus, and late complications are uncommon. The long-term outcome of patients with situs inversus was significantly better than that for patients with situs solitus.

A case of cyanotic L-transposition with complete heart block in an adult female who had three in-hospital normal deliveries

A 48-year-old female presented with complete heart block. On evaluation, it was diagnosed as a congenital cyanotic heart disease, namely, L-transposition of great arteries (L-TGA) with Fallot's physiology. She led the normal life of a manual laborer and had three hospital deliveries and yet escaped detection of her cardiac condition.

Current state of the art for use of pacemakers and defibrillators in patients with congenital cardiac malformations

As patients with congenital cardiac malformations increasingly survive therapeutic interventions, and our understanding of primary electrical diseases increases, the landscape of paediatric and congenital electrophysiology is expanding. Electrophysiologic abnormalities, both tachycardic and bradycardic, are commonly seen in post-operative patients with congenital cardiac disease, as well as being part of the natural history of congenital malformations and cardiomyopathies. Disturbances of rhythm represent an increasing morbidity in this population, and therapies using devices in the form of pacemakers and implantable cardioverter-defibrillators have taken on a correspondingly important role. In this review, we discuss some of the key features and recent advances in pacing for bradycardia, resynchronization pacing, anti-tachycardia pacing, and use of implantable cardioverter-defibrillators.

The right ventricle in congenital heart disease

In patients with congenital heart disease the right ventricle (RV) may support the pulmonary (subpulmonary RV) or the systemic circulation (systemic RV). During the last 50 years evidence is accumulating that RV dysfunction develops in many of these patients and leads to considerable morbidity and mortality. Therefore RV function in certain groups of congenital heart disease patients needs close surveillance and timely and appropriate intervention to optimise outcomes. Despite major progress being made, assessing the RV either in the subpulmonary or the systemic circulation remains challenging, often requiring a multi-imaging approach and expertise (echocardiography, magnetic resonance imaging, nuclear and occasionally invasive assessment with angiography). This review discusses the implications of volume and pressure loading of the RV in the context of congenital heart disease and describes the most relevant imaging modalities for monitoring RV function.

The prenatal diagnosis of, and short-term outcome for, patients with congenitally corrected transposition

Congenitally corrected transposition is a rare congenital anomaly, with only a few cases diagnosed and reported prenatally even in the largest fetal series. To determine the morphologic features and outcome for the lesion as recognized during fetal life, we reviewed the fetal and postnatal echocardiograms and medical records of 11 consecutive cases of congenitally corrected transposition. These were identified among 230 (4.7%) consecutive cases of structural cardiac disease referred to our fetal cardiology unit over a period of 4 years. The mean gestational age at diagnosis was 24.7 weeks. Reasons for referral were suspected complete transposition, abnormal position of the heart, and bradyarrhythmias. Associated cardiac lesions included an abnormal cardiac position in 6 cases, ventricular septal defect in 8, obstruction of the subpulmonary outflow tract in 6, tricuspid valvar displacement in 5, and complete atrioventricular block in 2. Only 3 of the cases had mild tricuspid regurgitation prior to birth. Termination was chosen in 4 cases with severe obstruction to pulmonary flow. Of the remaining cases, 2 patients died at 3 and 12 months after birth, respectively. Both developed significant tricuspid regurgitation associated with unexpected major arrhythmias. The remaining 5 patients are alive and relatively well at a mean follow-up of 25.4 months. An epicardial pacemaker was inserted in 1 because of complete atrioventricular block. We conclude that prenatal counseling must be guarded following the diagnosis of congenitally corrected transposition, even in fetuses with an apparently favorable state at initial examination. Some of these cases may undergo major and unexpected changes, particularly with regard to cardiac rhythm and tricuspid valvar function, with concomitant significant changes in prognosis.

Evaluation of syncope in adult congenital heart disease

Approximately one million adults in the United States have congenital heart disease. The practitioner who sees one of these patients presenting with syncope must have a thorough understanding of: the underlying disease process; the associated congenital heart abnormalities; the type of surgery performed; the potential surgical residua; and the natural and unnatural history of this type of heart disease. Several types of congenital heart disease including: atrial septal defects; ventricular septal defects; left-sided obstructive lesions; Ebstein Anomaly; tetralogy of Fallot; and transposition of the great arteries are reviewed.

Radiofrequency ablation of a posteroseptal atrioventricular accessory pathway in a left-sided tricuspid ring with Ebsteinlike anomaly in a patient with congenitally corrected transposition of the great arteries

Radiofrequency ablation successfully eliminated a posteroseptal accessory pathway in a left-sided tricuspid ring with Ebsteinlike anomaly in a patient with a congenitally corrected transposition of the great arteries.

Progressive tricuspid valve disease in patients with congenitally corrected transposition of the great arteries

BACKGROUND

The outcome of patients with corrected transposition of the great arteries (CTGA) is variably affected by associated intracardiac defects, tricuspid valve competence, and systemic right ventricular (RV) function. The relative importance of these factors in long-term outcome has not been evaluated.

METHODS AND RESULTS

Since 1958, 40 patients with CTGA were studied to determine risk factors for poor outcome, including age, open heart surgery, tricuspid insufficiency (TI), cardiac rhythm, pulmonary overcirculation, and RV dysfunction. Follow-up ranged from 7 to 36 years (mean 20 years). Intracardiac repair was performed in 21 patients; 19 were unoperated or had closed heart procedures. For the purposes of this study the designation TI(S) refers to at least moderately severe TI as delineated by echocardiogram and/or angiography. TI(s) was the only independently significant factor for death (P=0.01), and in turn, only the presence of a morphologically abnormal TV predicted TI(s)(P=0.03). Twenty-year survival without TI(S)was 93%, but only 49% with TI(S). Poor long-term postoperative outcome was due to TI(S) in all but 1 patient; 20-year survival rates for operated patients with and without TI(s)were 34% and 90%, respectively (P=0.002). Similarly, 20-year survival rates for unoperated patients with and without TI(s)were 60% and 100%, respectively, whether or not attempts to repair the TI were made (P=0.08).

CONCLUSIONS

TI(S)represents the major risk factor for CTGA patients; RV dysfunction appears to be almost always secondary to long-standing TI. Decisions related to surgical interventions with or without associated lesions must be strongly influenced by the status of the tricuspid valve.

Anatomic repair of corrected transposition or atrio-ventricular discordance: report of 8 cases

BACKGROUND

It is well recognized that a right ventricle (RV) may eventually fail if working as systemic. This has led to arterial switch operation for transposition of the great arteries (TGA), but more recently to anatomic correction of 'corrected transposition' or atrio-ventricular discordance (AVD) combining an atrial switch and a ventricular outflow repair (arterial switch or Rastelli type).

METHODS

We report here 8 cases of such anatomic correction of AVD in patients from 3 months to 10 years. Of these patients, 6 had situs solitus, and 2 situs inversus; 7 patients had a ventricular septal defect (VSD); 5 had an increased pulmonary flow, and 3 had a decreased pulmonary flow with pulmonary stenosis (PS) or pulmonary atresia (PA). In all, 6 had discordant and 1 had concordant ventriculo-arterial (VA) relations, and 1 had double-outlet RV, 2 had an associated coarctation, and 1 had a cor triatriatum. Of the 8 patients, 5 had pulmonary artery hypertension, 3 a moderate to severe tricuspid insufficiency and 6 had undergone one or more previous operations. Correction was done between 3 months and 10 years of age, with 7 having a Senning procedure (twice left-sided) and 1 a Mustard type operation. VA outflows were repaired with: 4 arterial switches, 1 left ventricle to aorta rerouting, 1 right ventricular outflow tract (RVOT) repair and 2 Rastelli. A tricuspid annuloplasty was done once.

RESULTS

All patients survived the operation, but 2 patients needed a reoperation (both successful): late obstruction of pulmonary venous channel after a left-sided Senning, and residual VSD closure. Mean follow-up is 45 months (3-122). Of the 8 patients, 6 patients are in sinus rhythm, 2 have junctional rhythm. A patient with junctional rhythm and occasional tachycardia died suddenly 18 months after surgery 1 week after satisfactory evaluation. All have a normal left ventricle function as evidenced by echocardiography.

CONCLUSIONS

Despite a more demanding procedure, the 'anatomic repair' of hearts with AVD is possible, even in infancy, with good early and mid-term result. Despite the potential late rhythmic problems of the Senning operation (somehow more frequent with AVD in our experience), it may become, with increasing experience, the procedure of choice in corrected transposition.

Intermediate-term outcome after intracardiac repair of associated cardiac defects in patients with atrioventricular and ventriculoarterial discordance

BACKGROUND

Limited information is available concerning long-term results, especially systemic right ventricular (RV) or tricuspid valvular function, after intracardiac repair of anomalies associated with discordant atrioventricular (AV) and ventriculoarterial (VA) connections ("congenitally corrected transposition of the great arteries").

METHODS AND RESULTS

We retrospectively reviewed the intermediate-term follow-up of 28 patients, totaling 158 patient-years (median, 60 months), after intracardiac repair involving closure of a ventricular septal defect (VSD) with or without additional surgery. Seven patients had VSD closure alone, 5 had VSD repair with pulmonary stenosis relief, and 16 had VSD closure with conduit insertion between left ventricle and main pulmonary artery. Hospital mortality was 4% (1 of 28 patients; 70% confidence limits, 0.07% to 12%) and the 1-, 5-, and 10-year actuarial survival probabilities were 89%, 83%, and 83%, respectively. Twenty-one of 24 long-term survivors were in New York Heart Association functional class I and 3 were in class II. Sixteen of 24 patients showed increasing tricuspid regurgitation (TR) of more than moderate degree, which occurred within 3 years after surgery in 7 patients. Twelve of 22 patients showed deterioration of RV pump function, mainly (9 of 12 patients) within 3 years postoperatively. The pulmonary to systemic flow ratio at the preoperative cardiac catheter study was significantly (P < .05) higher in patients who developed RV dysfunction (2.3 +/- 1.0, mean +/- SD) than in those with well-maintained RV function (1.4 +/- 0.6).

CONCLUSION

Intermediate-term results of intracardiac repair for AV and VA discordance were satisfactory in terms of survival and clinical functional status; however, there is concern about systemic RV dysfunction with development of TR relatively early after the operation. Alternative surgical approaches such as anatomic correction or Fontan repair for cases unsuitable for biventricular repair may improve the long-term results, including ventricular and valvular function.

Systemic atrioventricular valve replacement in an infant with corrected transposition of the great arteries

A 3-month-old infant with corrected transposition of the great arteries and severe systemic atrioventricular valve regurgitation due to "Ebstein-like anomaly" is reported. Through a right thoracotomy and longitudinal left atrial incision, a 19-mm St. Jude Medical valve was implanted into the annulus without removing the native valve. He is doing well 7 months after operation.

The natural and "unnatural" history of congenitally corrected transposition

The data available on 111 patients with congenitally corrected transposition and 2 adequate ventricles managed over the 20-year period to 1988 were reviewed retrospectively. The ages of survivors ranged from 1 to 58 years (median 20) and all but 10 had additional anatomic abnormalities. Tricuspid valve abnormalities were more prevalent in patients symptomatic with heart failure (26 of 43 patients) than those whose main problem was cyanosis (11 of 52 patients); all dysplastic or Ebstein valves were at least moderately incompetent. Intracardiac repair of the lesion was attempted in 51 patients with 11 early deaths; in multivariate models, the risk factors for early death or a bad early outcome or poor result 6 months later related to poor preoperative symptomatic status (especially from heart failure), impaired right ventricular function, heart block and younger age at surgery. Patients with more than mild preoperative tricuspid regurgitation whose valves were not replaced did very poorly. Thus, patients symptomatic from heart failure should probably be repaired early in the natural history of the disease, before the systemic right ventricles dilate. By contrast, the course of patients who were predominantly cyanosed was more stable in early childhood and their surgical outcome was less compromised by poor preoperative symptomatic status; their intracardiac repair can probably be delayed until symptoms become unacceptable.

Fetal complete heart block: antenatal diagnosis, significance and management

Complete heart block was diagnosed prenatally in 21 fetuses. Associated structural cardiac defects were present in 18 fetuses, in particular complete atrioventricular canal with atrial isomerism (5 cases), and 'corrected' transposition of the great arteries (4 cases). Maternal systemic lupus erythematosus was proved in only one case. In 11 fetuses, intra-uterine congestive heart failure with the signs of non-immune hydrops fetalis occurred. In all 11 fetuses, the hydrops was associated with a cardiac defect, in particular complete atrioventricular canal with atrial isomerism in 5 cases. A review of the literature confirms that only the association of complete heart block and cardiac malformation can cause intra-uterine congestive heart failure, whereas in the case of fetal complete heart block without cardiac malformation or with prenatally hemodynamically insignificant cardiac malformation, congestive heart failure is rare. Only 30% of newborns with complete heart block have associated cardiac malformations. In our series, however, 86% of the fetuses with complete heart block had cardiac malformations. The most important reason for this percentage discrepancy is that almost all fetuses with associated severe cardiac defects, in particular atrioventricular canal defects, develop heart failure which frequently results in prenatal death. Thus, fetal deaths are not included in pediatric statistics. Nevertheless, fetuses with isolated complete heart block generally do not develop heart failure and in almost all of the cases are born alive.