Pulmonary outflow obstruction protects against heart failure in adults with congenitally corrected transposition of the great arteries

Pathogenesis and Surgical Treatment of Congenitally Corrected Transposition of the Great Arteries (ccTGA): Part III

Congenitally corrected transposition of the great arteries (ccTGA) is an infrequent and complex congenital malformation, which accounts for approximately 0.5% of all congenital heart defects. This defect is characterized by both atrioventricular and ventriculoarterial discordance, with the right atrium connected to the morphological left ventricle (LV), ejecting blood into the pulmonary artery, while the left atrium is connected to the morphological right ventricle (RV), ejecting blood into the aorta. Due to this double discordance, the blood flow is physiologically normal. Most patients have coexisting cardiac abnormalities that require further treatment. Untreated natural course is often associated with progressive failure of the systemic right ventricle (RV), tricuspid valve (TV) regurgitation, arrhythmia, and sudden cardiac death, which occurs in approximately 50% of patients below the age of 40. Some patients do not require surgical intervention, but most undergo physiological repair leaving the right ventricle in the systemic position, anatomical surgery which restores the left ventricle as the systemic ventricle, or univentricular palliation. Various types of anatomic repair have been proposed for the correction of double discordance. They combine an atrial switch (Senning or Mustard procedure) with either an arterial switch operation (ASO) as a double-switch operation or, in the cases of relevant left ventricular outflow tract obstruction (LVOTO) and ventricular septal defect (VSD), intra-ventricular rerouting by a Rastelli procedure. More recently implemented procedures, variations of aortic root translocations such as the Nikaidoh or the half-turned truncal switch/en bloc rotation, improve left ventricular outflow tract (LVOT) geometry and supposedly prevent the recurrence of LVOTO. Anatomic repair for congenitally corrected ccTGA has been shown to enable patients to survive into adulthood.

Subpulmonary ventricular function and inflammation are related to clinical heart failure in patients with a systemic right ventricle

Background

Timely diagnosis of heart failure (HF) in patients with a systemic right ventricle (sRV) is difficult but important since clinical deterioration is fast once HF develops. We aimed to compare echocardiography and biomarker profile between sRV patients with and without HF and patients with a systemic left ventricle diagnosed with HF (sLV-HF).

Methods and results

Eighty-seven sRV patients and 30 sLV-HF patients underwent echocardiographic evaluation and blood sampling. Compared to sRV patients without HF, sRV-HF patients had more remodeling of the subpulmonary LV (spLV) (internal diameter 3.9 cm [3.3-5.7] vs 3.4 cm [2.9-3.9], P = 0.03, posterior wall 0.93 cm [0.76-1.20] vs 0.71 cm [0.59-0.91], P = 0.006) and lower spLV systolic function: ejection fraction (59 % ± 14 vs 70 % ± 10, P = 0.011), mitral annular plane systolic excursion (1.7 cm ± 0.5 vs 2.1 cm ± 0.4, P = 0.003), fractional area change (47 % [38-58] vs 59 % [51-70], P = 0.002) and lateral strain rate (-1.2/s ± 0.46 vs -1.5/s ± 0.39, P = 0.016). Inflammatory biomarkers were higher in sRV-HF patients compared to those without HF: red cell distribution width (13.3 fL [12.8-14.1] vs 12.6 fL [12.3-13.1], P < 0.001), neutrophil lymphocyte ratio (NLR, 3.7 [2.2-4.9] vs 2.4 [1.9-3.0], P = 0.015), C-reactive protein (CRP, 2.5 mg/dL [1.0-4.2] vs 1.2 mg/dL [0.0-2.0], P = 0.005) and compared to sLV-HF patients (NLR (3.7 [2.2-4.9] vs 2.5 [1.7-3.3], P = 0.044) and CRP (2.5 mg/dL [1.0-4.2] vs 0.85 mg/dL [0.6-2.0], P = 0.006).

Conclusion

Biventricular echocardiographic evaluation with a focus on the subpulmonary LV together with assessing inflammatory status in sRV patients could help in an earlier detection of HF.

Surgical Considerations for the Mitral Valve in Congenitally Corrected Transposition

BACKGROUND

Systemic atrioventricular valve (morphologic tricuspid valve [TV]) regurgitation has been implicated in the development of systemic ventricular failure in congenitally corrected transposition of the great arteries (ccTGA), leading to timely referral for valve replacement. However, the surgical management of subpulmonary atrioventricular valve (morphologic mitral valve [MV]) regurgitation and outcomes has not been well studied.

METHODS

Of 108 ccTGA patients undergoing atrioventricular valve surgery from 1979 to 2022, 22 patients (20%) underwent MV surgery. Demographics, etiology of valve regurgitation, operative details, and outcomes of these 22 patients were retrospectively reviewed. Follow-up at 1, 5, and 10 years was available for 18 (82%), 13 (59%), and 11 patients (50%), respectively.

RESULTS

Median age was 37 years (interquartile range, 29-57 years). Intrinsic MV pathology was present in 18 individuals (82%). Operations included repair in 16 patients (73%), replacement in 6 (27%), and concomitant replacement of TV in 16 (73%). There was 1 perioperative death (5%) in a patient undergoing an emergent operation for severe acute-on-chronic heart failure due to worsening TV regurgitation. During a median follow-up of 12 years (interquartile range, 2-19 years), 7 patients (32%) died. Among the 16 patients who underwent repair, recurrent moderate or greater regurgitation was seen in 15%, 29%, and 43% of repairs in patients with annular, leaflet, and lead-induced regurgitation, respectively.

CONCLUSIONS

Concomitant TV and MV disease occur much less frequently than isolated TV disease in ccTGA. Intrinsic MV disease is most commonly observed but appears less amenable to successful repair compared with mitral repair in the systemic position and suggests MV replacement may be preferred in ccTGA patients.

Long-term outcome of patients with transposition of the great arteries and a systemic right ventricle: A systematic review and meta-analysis

BACKGROUND

Patients with a transposition of the great arteries (TGA) and a systemic right ventricle are at risk of heart failure (HF) development, arrhythmia and early mortality. Prognostic evaluations in clinical studies are hampered by small sample sizes and single-centred approaches. We aimed to investigate yearly rate of outcome and factors affecting it.

METHODS

A systematic literature search of four electronic databases (PubMed, EMBASE, Web of Science and Scopus) was conducted from inception to June 2022. Studies reporting the association of a systemic right ventricle with mortality with a minimal follow-up of 2 years during adulthood were selected. Incidence of HF hospitalization and/or arrhythmia were captured as additional endpoints. For each outcome, a summary effect estimate was calculated.

RESULTS

From a total of 3891 identified records, 56 studies met the selection criteria. These studies described the follow-up (on average 7.27 years) of 5358 systemic right ventricle patients. The mortality incidence was 1.3 (1-1.7) per 100 patients/year. The incidence of HF hospitalization was 2.6 (1.9-3.7) per 100 patients/year. Predictors of poor outcome were a lower left ventricular (LV) and right ventricular ejection fraction (RVEF) (standardized mean differences (SMD) of -0.43 (-0.77 to -0.09) and - 0.85 (-1.35 to -0.35), respectively), higher plasma concentrations of NT-proBNP (SMD of 1.24 (0.49-1.99)), and NYHA class ≥2 (risk ratio of 2.17 (1.40-3.35)).

CONCLUSIONS

TGA patients with a systemic right ventricle have increased incidence of mortality and HF hospitalization. A lower LVEF and RVEF, higher levels of NT-proBNP and NYHA class ≥2 are associated with poor outcome.

End-stage heart failure in congenitally corrected transposition of the great arteries: a multicentre study

BACKGROUND AND AIMS

For patients with congenitally corrected transposition of the great arteries (ccTGA), factors associated with progression to end-stage congestive heart failure (CHF) remain largely unclear.

METHODS

This multicentre, retrospective cohort study included adults with ccTGA seen at a congenital heart disease centre. Clinical data from initial and most recent visits were obtained. The composite primary outcome was mechanical circulatory support, heart transplantation, or death.

RESULTS

From 558 patients (48% female, age at first visit 36 ± 14.2 years, median follow-up 8.7 years), the event rate of the primary outcome was 15.4 per 1000 person-years (11 mechanical circulatory support implantations, 12 transplantations, and 52 deaths). Patients experiencing the primary outcome were older and more likely to have a history of atrial arrhythmia. The primary outcome was highest in those with both moderate/severe right ventricular (RV) dysfunction and tricuspid regurgitation (n = 110, 31 events) and uncommon in those with mild/less RV dysfunction and tricuspid regurgitation (n = 181, 13 events, P < .001). Outcomes were not different based on anatomic complexity and history of tricuspid valve surgery or of subpulmonic obstruction. New CHF admission or ventricular arrhythmia was associated with the primary outcome. Individuals who underwent childhood surgery had more adverse outcomes than age- and sex-matched controls. Multivariable Cox regression analysis identified older age, prior CHF admission, and severe RV dysfunction as independent predictors for the primary outcome.

CONCLUSIONS

Patients with ccTGA have variable deterioration to end-stage heart failure or death over time, commonly between their fifth and sixth decades. Predictors include arrhythmic and CHF events and severe RV dysfunction but not anatomy or need for tricuspid valve surgery.

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.

Late outcome, therapy and systemic ventricular function in patients with a systemic right ventricle: data of the German National Register for Congenital Heart Defects

BACKGROUND

Adults with systemic right ventricle have a significant risk for long-term complications such as arrhythmias or heart failure.

METHODS

A nationwide retrospective study based on the German National Register for Congenital Heart Disease was performed. Patients with transposition of the great arteries after atrial switch operation or congenitally corrected TGA were included.

RESULTS

Two hundred and eight-five patients with transposition of the great arteries after atrial switch operation and 95 patients with congenitally corrected transposition of the great arteries were included (mean age 33 years). Systolic function of the systemic ventricle was moderately or severely reduced in 25.5 % after atrial switch operation and in 35.1% in patients with congenitally corrected transposition. Regurgitation of the systemic atrioventricular valve was present in 39.5% and 43.2% of the cases, respectively. A significant percentage of patients also had a history for supraventricular or ventricular arrhythmias. However, polypharmacy of cardiovascular drugs was rare (4.5%) and 38.5 % of the patients did not take any cardiovascular medication. The amount of cardiovascular drugs taken was associated with NYHA class as well as systemic right ventricular dysfunction. Patients with congenitally corrected transposition were more likely to receive pharmacological treatment than patients after atrial switch operation.

CONCLUSION

A significant portion of patients with systemic right ventricle suffer from a relevant systemic ventricular dysfunction, systemic atrioventricular valve regurgitation, and arrhythmias. Despite this, medication for heart failure treatment is not universally used in this cohort. This emphasises the need for randomised trials in patient with systemic right ventricle.

Management Options for Congenitally Corrected Transposition: Which, When, and for Whom?

Management strategies for congenitally corrected transposition of the great arteries (ccTGA) historically consisted of a physiologic repair, resulting in the morphologic right ventricle (mRV) supporting systemic circulation. This strategy persisted despite the development of heart failure by middle age because of the reasonable short-term outcomes, and the natural history of some patients with favorable anatomy (felt to demonstrate the mRV's ability to function in the long-term), and due to the less-than-optimal outcomes associated with anatomical repair. As outcomes with anatomical repair improved, and the long-term risk of systemic mRV dysfunction became apparent, more have begun to realize its advantages. In addition to the decision on whether or not to pursue anatomical repair, and the optimal timing, studies demonstrating the nuance to morphologic left ventricle retraining have demonstrated its feasibility. Further considerations in ccTGA have begun to be better understood, including: the management of a poorly functioning mRV, systemic tricuspid valve regurgitation, the utility of morphologic left ventricle outflow tract obstruction (native or surgically created) and pacing strategies. While some considerations are apparent: biventricular pacing is superior to univentricular, tricuspid regurgitation must be managed early with either progression towards anatomical repair (pulmonary artery banding if needed for retraining) or tricuspid replacement (not repair) based on the patient's age; others remain to be completely elucidated. Overall, the heterogeneity of ccTGA, as well as the unique presentation with each patient regarding ventricular and valvular function and center-to-center variability in management strategies has made the interpretation of published data difficult. That said, more recent long-term outcomes favor anatomical repair in most situations.

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.

Heart failure therapy based on interventricular mechanics and cardio-vascular communications

The heart should not be divided in right and left, whether in health nor in disease. However, the morphological and functional differences between the right and left ventricle should be known and the impact of the ventricle's position considered. Further, the parameters beyond heart rate, contractility, pre- and afterload guaranteeing a sufficient systemic cardiac output have to be integrated in therapeutic measures; preferentially the influence of interventricular mechanics. Despite of recent developments of specific drug therapies, heart failure is associated with a high rate of morbidity and mortality in children. During the progression of heart failure, pulmonary vascular disease is the consequence or the reason for further failing. Clinical symptoms are associated with congestion and low cardiac output at rest or exercise. Improved understanding of the pathophysiological mechanisms particularly of ventricular failure has resulted in the development of innovative therapies that target atrial/ventricular/arterial interactions. Recent advances in interventional and surgical approaches provide promising new strategies to deal with right and left ventricular deterioration. These techniques may delay listing for heart and (heart-) lung transplantation or even make redundant in individual cases. The beneficial effects of these ventricular interaction strategies are mainly based on the mechanics of the interventricular septum and improvement of systolic and diastolic ventricular performance.

15-Year follow-up of regional right and left ventricular function after the Senning operation: a Colour-Doppler myocardial imaging study

INTRODUCTION

Despite right ventricular (RV) dysfunction being a major concern in Senning patients, long-term follow-up data is lacking. This study aimed (1) at evaluating regional (base-mid-apex) RV and left ventricular (LV) function using Colour-Doppler myocardial imaging over a 15-year follow-up period and (2) at comparing results with matched controls.

METHODS

For the longitudinal analysis (2004-2019), we compared systolic and diastolic function in 10 Senning patients. For the cross-sectional analysis, we compared the subaortic RV (sRV) of Senning patients with the RV and LV of matched controls and the subpulmonary LV (spLV) of Senning patients with the LV of matched controls.

RESULTS

The longitudinal analysis of sRV function showed a significant decrease in apical peak systolic strain (-17 ± 7% vs -12 ± 4%; p = 0.025) and apical peak systolic strain rate (-1.1 ± 0.3s^-1 vs -0.8 ± 0.4s^-1; p = 0.012). spLV function showed a significant decrease in peak systolic velocity (mid; p = 0.013 and apex; p = 0.011) and peak systolic strain rate (mid; p = 0.048). The cross-sectional analysis revealed significant lower values for basal, mid and apical peak systolic velocity, peak systolic strain rate, peak systolic strain of the sRV of Senning patients when compared to both LV and RV of matched controls (all p < 0.05).

CONCLUSION

Our study showed that systolic and diastolic sRV function did not change over a 15-year follow-up period, except in the apical region. There was a decline in spLV systolic function, which may be of clinical value. On the other hand, when compared to age- and gender-matched controls, the sRV of Senning patients exhibits significantly decreased measurements of longitudinal systolic function.

The Fate of Congenitally Corrected Transposition of the Great Arteries Unoperated Before Adulthood

BACKGROUND

The outcomes, therapeutic strategies, and risk factors of congenital corrected transposition of great arteries (ccTGA) unoperated before adulthood are unclear.

METHODS

From October 2009 to January 2018, 117 adult ccTGA patients, classified into ccTGA with intact ventricular septum, ventricular septum defect, and pulmonary valve or subpulmonary outflow tract stenosis (PS) groups, were reviewed. Statistical analysis was performed with SPSS 19.0 (IBM, Armonk, NY).

RESULTS

At the first visit, no patients suffered operation. The PS group had the least systemic atrioventricular valve regurgitation and the greatest systemic ventricular ejection fraction. All 49 patients underwent surgery. From the first visit to last follow-up, systemic ventricular ejection fraction of unoperated ccTGA decreased significantly. In the intact ventricular septum group, patients receiving systemic atrioventricular valve replacement/valvuloplasty had a significantly increased systemic ventricular ejection fraction and statistically more freedom from death and transplant than unoperated. In the ventricular septum defect group the late systemic ventricular ejection fraction of operated patients was not statistically different from their basic data at first visit. In the PS group patients receiving physiologic repair had significantly decreased systemic ventricular ejection fractions. Severe systemic atrioventricular valve regurgitation, physiologic repair, and systemic ventricular dysfunction (ejection fraction <40%) were risk factors for mortality, transplant, and congestive heart failure.

CONCLUSIONS

PS protects against systemic atrioventricular valve regurgitation and ventricular dysfunction. Systemic atrioventricular valve replacement/valvuloplasty improved systemic ventricular function for ccTGA with an intact ventricular septum. Physiologic repair was not ideal for ccTGA with PS. Severe systemic atrioventricular valve regurgitation and systemic ventricular dysfunction were associated with suboptimal outcomes.

Diagnosis and treatment of right ventricular dysfunction in congenital heart disease

Right ventricular (RV) function is important for clinical status and outcomes in children and adults with congenital heart disease (CHD). In the normal RV, longitudinal systolic function is the major contributor to global RV systolic function. A variety of factors contribute to RV failure including increased pressure- or volume-loading, electromechanical dyssynchrony, increased myocardial fibrosis, abnormal coronary perfusion, restricted filling capacity and adverse interactions between left ventricle (LV) and RV. We discuss the different imaging techniques both at rest and during exercise to define and detect RV failure. We identify the most important biomarkers for risk stratification in RV dysfunction, including abnormal NYHA class, decreased exercise capacity, low blood pressure, and increased levels of NTproBNP, troponin T, galectin-3 and growth differentiation factor 15. In adults with CHD (ACHD), fragmented QRS is independently associated with heart failure (HF) symptoms and impaired ventricular function. Furthermore, we discuss the different HF therapies in CHD but given the broad clinical spectrum of CHD, it is important to treat RV failure in a disease-specific manner and based on the specific alterations in hemodynamics. Here, we discuss how to detect and treat RV dysfunction in CHD in order to prevent or postpone RV failure.

Incidental congenitally corrected transposition of the great arteries (ccTGA) in an adult with suspected coronary artery disease: review on radiological features and pathophysiology

We report a case of a 46-year-old woman who has presented to a peripheral hospital with progressive exertional dyspnoea and chest discomfort. The resting ECG showed features of left-sided ventricular hypertrophy. The initial chest radiograph was reported as cardiomegaly. Initial echocardiography revealed left atrial dilatation and ‘left ventricular’ hypertrophy with normal ejection fraction. She was treated as possible coronary artery disease and was subsequently referred to our centre for CT coronary angiography. Findings from the CT scan were consistent with congenitally corrected transposition of the great arteries (ccTGA). This report describes the radiological features of ccTGA, its associated cardiovascular anomalies, pathophysiology and potential complications.

Congenitally corrected transposition of the great arteries

Congenitally corrected transposition of the great arteries (CCTGA) is a rare congenital heart lesion with varied morphological presentation and can often by asymptomatic. A failing systemic right ventricle (RV) or increasing tricuspid regurgitation are generally indications for surgical intervention. The surgical approach depends upon the age of the patient and morphology of the lesion. Anatomical correction is associated with satisfactory long-term results.

Hemodynamically balanced congenitally corrected transposition of the great arteries with a large ventricular septal defect, and subvalvular pulmonic stenosis: a case report

Background

Adults with unoperated congenitally corrected transposition of the great arteries are rare but form a distinct group among adults with congenital heart disease. Patients with congenitally corrected transposition of the great arteries often have one or more associated cardiac anomalies that dictate the need for, and timing of, surgical intervention in childhood. However, in a proportion of patients, the hemodynamics does not require surgical attention during childhood, and, in some patients, a correct diagnosis is not established until adulthood. Here we report an adult case of unoperated congenitally corrected transposition of the great arteries with a large ventricular septal defect and probable pulmonary arterial hypertension.

Case presentation

Our patient was a 46-year-old Korean man. Transthoracic echocardiography and cardiac catheterization demonstrated hemodynamically balanced ventricles with a non-regurgitant systemic atrioventricular valve, normal pulmonary arterial pressure, and a reasonable difference between the oxygen saturation values of the aorta and pulmonary trunk, even with the presence of a large ventricular septal defect. Further morphological assessments using cardiac computed tomography and three-dimensional modeling/printing of his heart revealed that the mitral valve was straddling over the posteriorly positioned ventricular septal defect, which could explain the functional and anatomical subvalvular pulmonary stenosis and a small amount of shunt flow through the large ventricular septal defect. We interpreted this combination of cardiac defects as able to sustain his stable cardiac function. Thus, we decided to maintain his unoperated status.

Conclusion

A detailed anatomical understanding based on transthoracic echocardiography, cardiac computed tomography, and three-dimensional printing can justify a decision to not operate in cases of congenitally corrected transposition of the great arteries with hemodynamically balanced pulmonary stenosis and a ventricular septal defect, as observed in the present case.

Electronic supplementary material

The online version of this article (10.1186/s13256-019-2145-1) contains supplementary material, which is available to authorized users.

Anatomic Repair of Corrected Transposition of the Great Arteries: The Double Switch

The long-term outcome of patients with corrected transposition of the great arteries and associated lesions after physiologic repair is uncertain. Anatomic correction, utilizing the morphologic left ventricle as a systemic pumping chamber and the mitral valve as the systemic atrioventricular valve, is considered the preferred method, especially for patients with either tricuspid valve regurgitation, with Ebstein's malformation of the tricuspid valve, or with right ventricular dysfunction. The double switch employs both an atrial switch and arterial switch to "correct" the atrioventricular and ventriculoarterial discordance. Associated lesions are also repaired. The best outcomes with double switch are achieved with patients in the first few years of life even if reconditioning of morphologic left ventricle is required. However, the long-term function of the conduction system, the aortic valve, and the ventricles is variable and requires close surveillance.

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.

Origins and consequences of congenital heart defects affecting the right ventricle

Congenital heart disease is a major health issue, accounting for a third of all congenital defects. Improved early surgical management has led to a growing population of adults with congenital heart disease, including patients with defects affecting the right ventricle, which are often classified as severe. Defects affecting the right ventricle often cause right ventricular volume or pressure overload and affected patients are at high risk for complications such as heart failure and sudden death. Recent insights into the developmental mechanisms and distinct developmental origins of the left ventricle, right ventricle, and the outflow tract have shed light on the common features and distinct problems arising in specific defects. Here, we provide a comprehensive overview of the current knowledge on the development into the normal and congenitally malformed right heart and the clinical consequences of several congenital heart defects affecting the right ventricle.

Cardiac Ventricular Contractile Responses to Chronically Increased Afterload Secondary to Right Ventricular Outflow Obstruction in Patients With Tetralogy of Fallot

We examined the adaptive mechanism of the pulmonary ventricle (PV) in response to increased afterload secondary to pulmonary stenosis in tetralogy of Fallot (TOF, n = 47) and congenitally corrected transposition of the great arteries (cCTGA, n = 18), where the PV is morphologically different. We also elucidated the effects of such adaptation on systemic ventricular (SV) function. PV contractility, assessed by dp/dt_max, showed significant positive correlations with PV pressure (r = 0.82, p <0.01 for TOF and r = 0.78, p <0.01 for cCTGA) and pulmonary-to-systemic ventricular pressure ratio (r = 0.70, p <0.01 for TOF and r = 0.76, p <0.01 for cCTGA) in patients with both TOF and cCTGA. Notably, the slopes of these correlations were significantly higher in cCTGA than in TOF (p <0.01), suggesting enhanced contractile responses in cCTGA. Moreover, SV dp/dt_max showed significant positive correlations with PV dp/dt_max in patients with both TOF and cCTGA (r = 0.67, p <0.01 and r = 0.61, p <0.01, respectively), indicating positive ventricular-ventricular interaction. In this relationship, the slopes of correlations were significantly higher in TOF than in cCTGA (p = 0.024). These results, indicating different behaviors of PV contractile physiology and its interaction with the SV, may have important therapeutic implications when considering medical, catheter, and surgical interventions for pulmonary stenosis in these diseases. The results may also offer the potential for a new approach for improvement of prognosis, especially in cCTGA.

Severe subvalvular pulmonic stenosis due to a ball-shaped accessory tissue in an asymptomatic woman with congenitally corrected transposition of great arteries and mesocardia: A rare case report

Congenitally corrected transposition of great arteries (CCTGA) is a rare anomaly described by atrioventricular and ventriculoarterial discordance. On the other hand, mesocardia that is extremely rare includes two relatively well-defined apexes defined by each ventricle with the major axis of the heart lies in the midline. We describe a rare case of an asymptomatic 20-year-old woman with mesocardia, CCTGA, and severe subvalvular pulmonic stenosis due to a ball-shaped accessory tissue in left ventricular outflow tract.

Promising Outcome of Anatomic Correction of Corrected Transposition of the Great Arteries

BACKGROUND

Anatomic correction of corrected transposition of the great arteries with associated lesions, utilizing the morphologic left ventricle as a systemic pumping chamber, is the preferred method in many centers. The purpose of this study was to analyze functional outcome after anatomic correction.

METHODS

Between Jan 1997 and May 2016, 63 patients with corrected transposition of the great arteries and associated lesions underwent anatomic correction. Forty-two patients (67%) underwent palliation before correction, including 14 patients (22%) who required training of systemic ventricle. The double switch procedure was performed in 37 patients; 25 patients underwent the Senning-Rastelli operation, and 1 patient underwent the Senning-Nikaidoh procedure. The median age at correction was 1.6 ± 3.7(SD) years (range, 0.2 to 17.8 years).

RESULTS

The survival and freedom from any event was 95% and 71%, respectively, at 15-year follow-up. The combined freedom from death, failure of systemic ventricle, or heart transplant was 93% at 15-year follow-up regardless of procedure type. Sinus rhythm was present in 49 patients, with 14 patients requiring pacemaker (22%)-8 preoperatively, 4 early postoperatively, and 2 late postoperatively. Neurological development is normal in all patients. Fifty-four percent of the patients are not on medication.

CONCLUSIONS

Anatomic correction of corrected transposition of the great arteries is a safe procedure that provides encouraging survival and functional benefits. Ninety-three percent preservation of morphological left ventricle function in 15 years of follow-up supports the concept of anatomic correction. Longer follow-up is needed to confirm superiority of this approach over other management strategies.