Ventricular Function in Physiologically Repaired and Unrepaired Congenitally Corrected Transposition of the Great Arteries.

In patients with congenitally corrected transposition of the great arteries (ccTGA) and hemodynamically significant concomitant lesions, physiologic repair may be undertaken, in which the circulation is septated but the morphologic right ventricle (RV) remains the systemic ventricle. Patients without significant concomitant lesions may be observed without surgery, with a similar physiologic result. We compared cardiovascular magnetic resonance measures of ventricular size and function in patients with physiologically repaired and unrepaired ccTGA. Patients with ccTGA who underwent cardiovascular magnetic resonance at our center between September 2007 and July 2019 were analyzed. In 38 patients identified (12, physiologically repaired; 26, unrepaired; mean age 34.5 [18.7 to 52.0] years), there was a higher proportion of RV ejection fraction ≤45% in physiologically repaired (75% vs unrepaired 35%, p = 0.02). Physiologically repaired patients had worse left ventricle global longitudinal strain (-14.9% ± 5.0% vs unrepaired patients -18.4% ± 2.7%, p = 0.04). The difference in tricuspid regurgitant fraction between groups did not achieve statistical significance (physiologically repaired 27.4 ± 11.1% vs unrepaired patients 19.2 ± 13.0%, p = 0.08). Evaluation for late gadolinium enhancement was more commonly undertaken in physiologically repaired patients (8 of 12 vs unrepaired 7 of 26, p = 0.03) and present more frequently in the left ventricle in physiologically repaired patients in patients evaluated (6 of 8 vs unrepaired 0 of 7, p = 0.01). In conclusion, ventricular function is decreased in patients with ccTGA undergoing physiologic repair compared with those without previous surgery. These cohorts should be considered separately when using ventricular function as an outcome. RV dysfunction is concerning for long-term outcomes following physiologic repair.

Role of Echocardiography for Assessment of Cardiac Remodeling in Congenitally Corrected Transposition of Great Arteries.

BACKGROUND: The purpose of this study was to assess the role of echocardiography for a comprehensive assessment of cardiac remodeling, and the relationship between indices of cardiac remodeling and cardiovascular events (defined as the composite end point of heart failure hospitalization, heart transplant, or cardiovascular death) in adults with congenitally corrected transposition of great arteries (cc-TGA). METHODS: This is a retrospective study of adults with cc-TGA who underwent echocardiogram (2003-2020). Offline image analysis was performed in all patients. Chamber (atrial and ventricular) function and size were assessed by strain imaging and 2-dimensional echocardiography. RESULTS: Of 233 patients with cc-TGA (40±15 years), 123 (55%) had at least one cardiac procedure before baseline echocardiogram. Of 233 patients, 76% and 61% had left atrial dysfunction and systemic right ventricular dysfunction, respectively; while 43% and 11% had right atrial dysfunction and left ventricular dysfunction, respectively. During a median follow-up of 8.9 years, 114 (49%) underwent additional cardiac procedures, and 66 (28%) had cardiovascular events. Left atrial reservoir strain, right ventricular global longitudinal strain, right atrial reservoir strain, left ventricular systolic pressure, and left ventricular global longitudinal strain were independently associated with cardiovascular events. CONCLUSIONS: In addition to the clinical importance of right ventricular systolic dysfunction in cc-TGA that is already well described, the current study demonstrated, for the first time, that biatrial dysfunction was common and was associated with clinical outcomes. Since there are currently no effective therapies for atrial and ventricular dysfunction in patients with cc-TGA, there is a need for research to identify novel strategies to prevent atrial and ventricular dysfunction in this population.

Outcomes of treatment pathways in 240 patients with congenitally corrected transposition of great arteries.

OBJECTIVE: Congenitally corrected transposition of the great arteries (ccTGA) encompasses a diverse morphologic cohort, for which multiple treatment pathways exist. Understanding surgical outcomes among various pathways and their determinants are challenged by limited sample size and follow-up, and heterogeneity. We sought to investigate these questions with a large cohort of ccTGA patients presenting at different ages and representing the full therapeutic spectrum. METHODS: Retrospective review of 240 patients diagnosed with ccTGA from Cleveland Clinic coupled with prospective cross-sectional follow-up. Forty-six patients whose definitive procedure was completed elsewhere were excluded. Time-related survival was described among treatment pathways using actuarial, time-varying covariate, and competing risks analyses. Temporal trends in longitudinal valve and ventricular function were assessed using nonlinear mixed-effects models. RESULTS: Median follow-up was 10 years. Seventy-nine patients with ccTGA underwent anatomic repair, 45 physiologic repair, 24 Fontan palliation, and 6 primary transplant. Forty patients managed expectantly had excellent long-term survival when considered from time of presentation, but benefited from failures captured following transition to physiologic repair or transplant. Morphologic right ventricular dysfunction after physiologic repair increased from 68% to 85% after 5 years, whereas morphologic left ventricular function was stable in anatomic repair, especially with early surgery. Transplant-free survival at 15 years for anatomic and physiologic repair was 80% and 71%, respectively. CONCLUSIONS: Early anatomic repair may be preferable to physiologic repair for select ccTGA patients. Late attrition after physiologic repair represents failure of expectant management and progressive tricuspid valve and morphologic right ventricular dysfunction compared with anatomic repair, where morphologic left ventricular function is relatively preserved.

Continuous-Flow Left Ventricular Assist Device Therapy in Adults with Transposition of the Great Vessels.

An increasing number of children with congenital heart disease are surviving into adulthood and subsequently developing end-stage heart failure. Two example populations are adults who have been previously operated on for congenitally corrected transposition of the great arteries (CCTGA) and transposition of the great arteries (TGA). Implantation of a continuous flow left ventricular assist device (CF-LVAD) in these patients can present unusual anatomical and physiologic challenges. In this report, we describe outcomes of CF-LVAD implantation in three such patients. These cases demonstrate the feasibility of implanting a CF-LVAD in patients who have undergone surgery for CCTGA and/or TGA.

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.

Long-term outcomes of arrhythmia and distinct electrophysiological features in congenitally corrected transposition of the great arteries in an Asian cohort.

Congenitally corrected transposition of the great arteries (ccTGA) is associated with various types of arrhythmia, including supraventricular tachycardia (SVT) and complete atrioventricular block (cAVB). Our study aims to characterize the arrhythmia burden, associated risk factors, arrhythmia mechanisms, and the long-term follow-up results in patients with ccTGA in a large Asian cohort. METHODS: We enrolled 104 patients (43 women and 61 men) diagnosed with ccTGA at our institution. The mean age at last follow-up was 20.8 years. RESULTS: For 40 patients (38%) with tachyarrhythmia, paroxysmal SVT (PSVT) and atrial arrhythmia were observed in 17 (16%) and 27 (26%) patients, respectively, with 4 patients (4%) having both types of SVT. The 20-year and 30-year SVT-free survival rates were 68% and 54%, respectively. Seven patients (7%) developed cAVB: 2 (2%) developed spontaneously, and the other 5 (5%) was surgically complicated (surgical risk of cAVB: 7%, all associated with ventricular septal defect repair surgery). PSVT was mostly associated with accessory pathways (5/9) but also related to twin atrioventricular nodal reentry tachycardia (3/9) and atrioventricular nodal reentry tachycardia (1/9). Most of the accessory pathways were located at tricuspid valve (9/10). Catheter ablation successfully eliminated all PSVT substrates (10/10) and most of the atrial arrhythmia substrates (3/5), with low recurrence rate. CONCLUSIONS: The arrhythmia burden in patients with ccTGA is high and increases over time. However, cAVB incidence was relatively low and kept stationary in this Asian cohort. The mechanisms of SVT are complicated and can be controlled through catheter ablation.

Congenitally corrected transposition and mitral atresia complicated by restrictive atrial septum.

Congenitally corrected transposition (ccTGA), also known as L-transposition of the great arteries (L-TGA), is a rare cardiac malformation accounting for approximately 0.05% of congenital heart disease, characterized by ventricular inversion, discordant ventriculo-arterial connections with a normal visceroatrial relationship. It was first described by Baron Rokitansky in 1875, and prenatal sonographic diagnosis can be difficult. Symptomatology and clinical presentation of this malformation are related to the associated intracardiac defects. We report a rare case of severe, complex cardiac disease: prenatally diagnosed ccTGA with atrial restriction, mitral atresia, Ebsteinoid tricuspid valve, and severe pulmonary valve stenosis, who subsequently developed left pulmonary vein stenosis.

Effect of medical treatment in patients with systemic right ventricle.

Objective: Congenitally corrected and surgical atrial redirected transposition of the great arteries (TGA) represents states where the morphological right ventricle serves as a systemic ventricle (S-RV). The S-RV is prone to failure, but data on medical treatment on this problem is limited. The purpose of this study was to evaluate the survival in adults with S-RV, with or without heart failure treatment. Design: The SWEDCON registry was used to collect data. All adults with S-RV and minimum follow-up of 1 year were included retrospectively. Medical treatment was defined as taking beta-blockers and/or ACE inhibitors and/or ARBs for more than 50% of the time. Results: We identified 343 patients with S-RV (median age: 21 years). Surgical atrial redirected TGA was present in 58% and congenitally corrected TGA in 42% of patients. The medically treated group (n = 126) had higher rates of impaired S-RV function, use of diuretics, pacemaker and higher NYHA functional class at baseline compared to controls. The proportion of patients with impaired functional class did not change over time in the medically treated group, but increased in controls (21% vs. 30%, p = .015). In Kaplan-Meier analysis, the mean follow-up was 10.3 years, no difference in survival was seen between the groups. Conclusions: Medical treatment may be beneficial in patients with S-RV and impaired functional class and appears to be safe in the long term. The treatment group had equal survival to controls, despite worse baseline characteristics, which might be a result of slower progression of disease in this group.

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.

Atrial tachycardia eliminated at the ventricular side in patients with congenitally corrected transposition of the great arteries: Electrophysiological findings and anatomical concerns.

BACKGROUND: The unique malformation of congenitally corrected transposition of the great arteries (cc-TGA) makes the pulmonary outflow tract (POT) a possible origin of atrial tachycardia (AT). OBJECTIVE: The purpose of this study was to investigate the mapping characteristics of ATs successfully ablated at the POT in patients with cc-TGA. METHODS: Patients with cc-TGA with AT eliminated at the POT were analyzed. Activation mapping of the atria and POT was performed under the guidance of a 3-dimensional electroanatomic mapping system. The activation pattern of these chambers was investigated, with the local activation time (LAT; using coronary sinus ostium as a reference) of the earliest activation site (EAS) being compared. RESULTS: AT eliminated at the POT was documented in 5 of 6 patients with cc-TGA. The EAS was at the right anteroseptal region with a LAT of 33 (21-120) ms in the right atrium and at the septal wall with a comparable LAT (26, 47, and 26 ms; P = .604) in the left atrium. The EAS of the POT was in the vicinity of the left-facing pulmonary sinus cusp in 3 cases and the nonfacing pulmonary sinus cusp in 2 cases, with a LAT of 106 (28-134) ms preceding both atria. Ablation at this site successfully eliminated AT in all 5 cases. CONCLUSION: AT arising adjacent to the POT is not an uncommon tachycardia in patients with situs solitus-type cc-TGA and can be safely eliminated by ablation targeting the EAS in the POT.

Effectiveness of Bidirectional Glenn Shunt Placement for Palliation in Complex Congenitally Corrected Transposed Great Arteries.

Surgery for complex congenitally corrected transposed great arteries is one of the greatest challenges in cardiovascular surgery. We report our experience with bidirectional Glenn shunt placement as a palliative procedure for complex congenitally corrected transposition. We retrospectively identified 50 consecutive patients who had been diagnosed with congenitally corrected transposition accompanied by left ventricular outflow tract obstruction and ventricular septal defect and who had then undergone palliative bidirectional Glenn shunt placement at our institution from January 2005 through December 2014. Patients were divided into 3 groups according to subsequent surgeries: Fontan completion (total cavopulmonary connection, 13 patients) (group 1), anatomic repair (hemi-Mustard and Rastelli procedures without Glenn takedown, 11 patients) (group 2), and prolonged palliation (no further surgery, 26 patients) (group 3). After shunt placement, no patient died or had ventricular dysfunction. Overall, mean oxygen saturation increased significantly from 79.5% ± 13.5% preoperatively to 94.1% ± 7.3% (P <0.001). The median time from shunt placement to Fontan completion and anatomic repair, respectively, was 2.1 years (range, 1.6-5.2 yr) and 1.1 years (range, 0.6-2.4 yr). Only 2 late deaths occurred, both in group 1. In group 3, time from shunt placement to latest follow-up was 4.5 years (range, 2.3-8 yr). At latest follow-up, mean oxygen saturation was 91.6% ± 10.3%, and no patients had impaired ventricular function. Bidirectional Glenn shunt placement as an optional palliative procedure for complex congenitally corrected transposition has favorable outcomes. Later, patients can feasibly be treated by Fontan completion or anatomic repair. Use of a bidirectional Glenn shunt for open-ended palliation is also acceptable.

Global longitudinal strain correlates to systemic right ventricular function.

BACKGROUND: The aim of this retrospective study was to evaluate the relationship between right ventricular function derived from cardiac magnetic resonance imaging (CMR), echocardiography and exercise stress test performance, NT-proBNP (N-terminal proB-type natriuretic peptide) level and NYHA class in patients with a systemic right ventricle. METHODS: All patients with congenitally corrected transposition of the great arteries (ccTGA), or transposition of the great arteries after Mustard or Senning procedures, (TGA) followed at our centre who had undergone CMR, echocardiography, an exercise stress test and blood sampling, were included in the study. RESULTS: We examined 11 patients (six after the Senning procedure, one after the Mustard procedure, and four ccTGA) who have a median age of 32 years (22-67 years). A significant correlation was observed between the systemic ventricular function, expressed as the CMR-derived right ventricular ejection fraction and the right ventricular global longitudinal strain (r= -0.627; p=0.039). CONCLUSION: We have demonstrated that in patients with ccTGA or TGA right ventricular global longitudinal strain may be useful in the evaluation of the systemic right ventricular function.

Left ventricular retraining in corrected transposition: Relationship between pressure and mass.

BACKGROUND: A subset of patients with corrected transposition of the great arteries (CC-TGA) will require left ventricular (LV) retraining before undergoing a double-switch procedure. LV retraining results in an immediate increase in LV pressure but not in LV mass. The purpose of this study was to evaluate the relationship between LV pressure and mass during LV retraining. METHODS: This was a retrospective review of 36 patients with CC-TGA who were enrolled in LV retraining. The median age at enrollment was 12 months. The majority (82%) had an Ebstenoid tricuspid valve or moderate to severe tricuspid valve regurgitation before pulmonary artery banding. RESULTS: Twenty-seven of the 36 patients underwent LV retraining and a double switch, including 14 patients with a single pulmonary artery band (PAB), 12 patients with 2 PABs, and 1 patient with 3 PABs. There was no early or late mortality associated with these procedures. Ninety percent of the patients demonstrated a linear relationship between LV pressure and mass; however, 3 patients (10%) demonstrated a different LV retraining pattern characterized by excess LV mass compared to LV pressure. Two of these 3 patients are LV retraining failures, whereas the third patient did undergo a double switch. CONCLUSIONS: The data show that the majority of patients enrolled in LV retraining have a predictable relationship between LV mass and pressure. A minority demonstrate an excess accrual of mass with respect to pressure load. These results suggest there may be an important distinction between normal and pathological hypertrophy during the LV retraining process.

In congenitally corrected transposition of great arteries following Fontan surgery, a left ventricle with suprasystemic systolic and high end-diastolic pressures paradoxically preserves right ventricular and tricuspid valve function.

Systemic right ventricular function in congenitally corrected transposition depends on septal geometry. Suprasystemic left ventricular systolic pressures and high end-diastolic pressures after Fontan surgery paradoxically preserve right ventricular function.

Exploring the Prognostic Value of Novel Markers in Adults With a Systemic Right Ventricle.

Background Adults with a systemic right ventricle (sRV) have a high risk of cardiac complications. This study aimed to identify prognostic markers in adults with sRV based on clinical evaluation, echocardiography, and blood biomarkers. Methods and Results In this prospective cohort study, consecutive clinically stable adults with sRV caused by Mustard- or congenitally corrected transposition of the great arteries were included (2011-2013). Eighty-six patients were included (age 37±9 years, 65% male, 83% New York Heart Association functional class I, 76% Mustard transposition of the great arteries, 24% congenitally corrected transposition of the great arteries). Venous blood sampling was performed including N-terminal pro B-type natriuretic peptide, high-sensitive-troponin-T, high-sensitivity C-reactive protein, growth differentiation factor-15, galectin-3, red cell distribution width, estimated glomerular filtration rate, and hemoglobin. Besides conventional echocardiographic measurements, longitudinal, circumferential, and radial strain were assessed using strain analysis. During a median follow-up of 5.9 (interquartile range 5.3-6.3) years, 19 (22%) patients died or had heart failure (primary end point) and 29 (34%) patients died or had arrhythmia (secondary end point). Univariable Cox regression analysis was performed using dichotomous or standardized continuous variables. New York Heart Association functional class >I, systolic blood pressure, and most blood biomarkers were associated with the primary and secondary end point (galectin-3 not for primary, N-terminal pro B-type natriuretic peptide and high-sensitivity C-reactive protein not for secondary end point). Growth differentiation factor-15 showed the strongest association with both end points (hazard ratios; 2.44 [95% CI 1.67-3.57, P<0.001], 2.00 [95% CI 1.46-2.73, P<0.001], respectively). End-diastolic basal dimension of the subpulmonary ventricle was associated with both end points (hazard ratio: 1.95 [95% CI 1.34-2.85], P<0.001, 1.70 [95% CI 1.21-2.38, P=0.002], respectively). Concerning strain analysis, only sRV septal strain was associated with the secondary end point (hazard ratio 0.58 [95% CI 0.39-0.86], P=0.006). Conclusions Clinical, conventional echocardiographic, and blood measurements are important markers for risk stratification in adults with a sRV. The value of novel echocardiographic strain analysis seems limited.