Longitudinal changes in systemic right ventricular remodeling in adult patients with transposition of the great vessels as assessed by cardiovascular magnetic resonance imaging.

BACKGROUND: Systemic right ventricular (sRV) physiology occurs in patients with congenitally corrected transposition of the great arteries (ccTGA) and D-TGA post atrial switch repair, and the natural history is of progressive sRV dysfunction. No study has assessed longitudinal changes in sRV remodeling by serial CMR. METHODS: Patients evaluated at two adult congenital heart disease centers and who underwent ≥2 CMR exams were studied. Indexed sRV end-diastolic volume (sRVEDVi), end-systolic volume (sRVESVi), and ejection fraction (sRVEF) were determined by a core laboratory. Concurrent echocardiograms were assessed for degree of systemic TR (sTR). Tricuspid valve events were defined as ≥moderate sTR, or interval tricuspid replacement (TVR). Generally, the earliest and most recent studies were compared. A subset of patients were followed with ≥moderate sTR, and then subsequently underwent interval TVR. For these patients, two study time-intervals were defined to analyze the impact of each event independently. RESULTS: 67 patients were studied (33±11 years, 47% male, 33% ccTGA), with 72 total time intervals studied (median interval 9.0 years [IQR 4.6-13.3]). There was a small increase in sRVEDVi over time (ΔsRVEDVi 5.5±15.8ml/m2, p<0.001), but mean change in sRVEF was not significant (ΔsRVEF 0.1±6.9%, p=0.86); notably, confidence intervals were wide for both. ccTGA patients had a trend towards greater decrement in sRVEF (ΔsRVEF -1.7±6.8 vs 1.3±6.7%, p=0.06). For each 25ml/m2 increase in baseline sRVEDVi, there was a 1.8% decrease in sRVEF (95% CI -3.2% to -0.5%, p=0.01). Patients without significant sTR had lesser deterioration in sRVEF compared to those with ≥moderate sTR or with interval TR intervention (ΔsRVEF 1.8±6.9% vs -2.1±6.6% and -2.6±4.5, p<0.05). Interval sRV conduction delay was associated with a trend towards greater decrements in sRVEF (ΔsRVEF -3.9±6.3 vs. 0.9±6.8%, p=0.07). Overall, underlying congenital anatomy, baseline sRVEDVi, advanced sTR or interval TVR, and sRV conduction delay explained only 16% of the variability in ΔsRVEF over time. CONCLUSIONS: Longitudinal changes in sRV remodeling were small, with great heterogeneity. Apparent risk factors in our study, namely underlying congenital anatomy, baseline sRVEDVi, TR events, and sRV conduction disease accounted for only 16% of the variability seen in the longitudinal change of sRVEF.

Multi-modality imaging of the systemic right ventricle in congenital heart disease.

A comprehensive and structured imaging approach in the evaluation of the systemic right ventricle (sRV) in patients with complete transposition of the great arteries (TGA) after atrial switch procedure and congenitally corrected transposition of the great arteries (ccTGA) is a key for their optimal lifelong surveillance. Despite the improvements in cardiovascular imaging of adults with congenital heart disease (ACHD), the imaging of sRV remains an ongoing challenge due to its complex morphology and the difficulty in applying the existing knowledge for the systemic left ventricle. While cardiac magnetic resonance (CMR) is considered the gold standard imaging method, echocardiographic evaluation is primarily preferred in everyday clinical setting. Although qualitative assessment of its systolic function is primarily used, the introduction of advanced echocardiographic techniques, such as speckle tracking echocardiography (STE) and three-dimensional echocardiography (3DE), has provided new insights into the optimal assessment of the sRV. Standardized quantitative parameters remain to be elucidated, and morphometric and mechanistic studies are warranted to validate reference ranges for the sRV. This review highlights the challenges in the optimal evaluation of sRV and summarizes the available imaging tools. HIGHLIGHTS: CMR is the gold standard imaging method of sRV. Qualitative assessment of the systolic function of sRV is primarily used. Advanced echocardiographic techniques (STE and 3DE) provide optimal sRV assessment. Reference ranges for the sRV indices are warranted to be validated.

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.

Special Considerations for Mechanical Circulatory Support or Device Therapy in Adult Congenital Heart Disease Heart Failure.

Heart failure has become the leading cause of mortality in adult congenital heart disease (ACHD) patients after the fifth decade of life. There is scanty evidence supporting the use of guideline-directed medical therapy in ACHD, especially in systemic right ventricle or single ventricle physiology. In complex patients, diagnosing heart failure and timely referral for advanced therapies are challenging. Mechanical circulatory support has been significantly developed over the past decade and has recently emerged as a feasible therapeutic option for these patients. This review summarizes current evidence of mechanical circulatory support in this population, its potential uses, and challenges.

Medical Therapy and Monitoring in Adult Congenital Heart Disease Heart Failure.

Heart failure (HF) in adult congenital heart disease (ACHD) is an increasingly common problem facing ACHD and advanced heart disease and transplant providers. Patients are highly nuanced, and therapies are poorly studied. Standard HF medications are often used in patients who are not targets of large clinical trials. HF management in this data-free zone requires focused, comprehensive team-based care and close follow-up and communication with patients.

An unmet need: arrhythmia detection by implantable loop recorder in the systemic right ventricle.

AIMS: Patients with systemic right ventricles are at high risk of sudden cardiac death. Arrhythmia is a significant risk factor. Routine Holter monitoring is opportunistic with poor adherence. The aim of this study was to determine if continuous rhythm monitoring with an implantable loop recorder (ILR) could allow early detection of clinically important arrhythmias. METHODS AND RESULTS: Implantable loop recorder implantation was offered to patients with atrial switch repair for transposition of the great arteries. Recordings were made with symptoms or, automatically for pauses, significant bradycardia or tachycardia and reviewed by the multi-disciplinary team. Twenty-four out of 36 eligible patients underwent ILR implantation with no complication. Forty-two per cent had preserved ventricular function, 75% were NYHA functional class I, 88% had low sudden cardiac death risk, 33% had previous intra-atrial re-entrant tachycardia (IART), and none had known conduction disease. Eighteen out of 24 (75%) patients made 52 recordings (52% automated) over 39.5 months (1.6-72.5). Thirty-two out of 52 (62%) recordings in 15/24 (63%) of the cohort were clinically significant and included sinus node disease (two patients), atrioventricular block (two patients), IART (seven patients), and IART with sinus node disease or atrioventricular block (four patients). Implantable loop recorder recordings prompted medication change in 11 patients [beta-blockers (n = 9), anti-coagulation (n = 5), and stopping anti-coagulation (n = 1)] and device therapy recommendation in seven patients [five pacemakers (three: atrioventricular block) and two defibrillators]. Two patients declined intervention; one suffered an arrhythmic death. Intra-atrial re-entrant tachycardia and clinically relevant conduction disease were detected in patients irrespective of sudden cardiac death risk. CONCLUSION: Continuous monitoring with an ILR in patients with systemic right ventricle following atrial switch detects clinically relevant arrhythmias that impact decision-making. In this cohort, clinically relevant arrhythmias did not correlate with sudden cardiac death risk.

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.

Valvular Regurgitation in Adults with Congenital Heart Disease and Heart Failure: Current Status and Potential Interventions.

The great majority of patients born with congenital heart disease (CHD) are living well into adulthood, yet they often have residual hemodynamic lesions, including valvar regurgitation. As these complex patients grow older, they are at risk of developing heart failure, which can be exacerbated by the underlying valvular regurgitation. In this review, we describe the etiologies of heart failure related to valvular regurgitation in the CHD population and discuss potential interventions.

Comparing Long-Term Sequelae of the Systemic Right Ventricle: An Overview of Single Versus Biventricular Arrangements.

Patients with systemic right ventricles (RV) are at risk for heart failure and sudden cardiac death. Contributing factors to RV dysfunction include increased afterload from the systemic circulation, coronary insufficiency, progressive tricuspid valve regurgitation, the presence of residual lesions after palliation and arrhythmias. While all patients with a systemic right ventricle (SRV) are vulnerable to heart failure, there are distinct differences between patients with congenital dextro-transpostion of the great arteries (d-TGA) repaired by atrial switch, unrepaired congenitally corrected transposition of the great arteries (cc-TGA) and single systemic right ventricles palliated with a Fontan operation. Herein, we explore both the similarities and differences in progression of heart failure by phenotype as well as both the advancements and limitations in treatment options by each type of SRV.

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.

Subjective and Objective Impact of Angiotensin Receptor-Neprilysin Inhibitors on Systemic Right Ventricle Patients.

INTRODUCTION: Patients with adult congenital heart disease (ACHD) who have an anatomic right ventricle supporting the systemic circulation have increased mortality and morbidity from heart failure (HF). Angiotensin receptor-neprilysin inhibitors (ARNI) have emerged as a standard of therapy for adults with HF. However, the effects of this therapy have not been extensively studied in ACHD patients, especially those with systemic right ventricle (SRV). HYPOTHESIS: ARNIs are associated with subjective and objective improvement in SRV patients. METHODS: Eighteen (18) SRV patients were prescribed ARNI at our institution in the last 5 years. Data before and during treatment, including demographics, medical history, New York Heart Association functional class (NYHA FC), labs, cardiac computed tomography (CT) or magnetic resonance imaging (MRI), echocardiographic measurements, cardiopulmonary stress test (CPET), and hospitalisation for HF were obtained by review of the electronic medical record. Statistical analysis was performed using paired t and Wilcoxon rank sum tests. RESULTS: Eighteen (18) SRV patients (mean age 40 yrs, 72% male) were treated with ARNI (median duration 13 mo) in addition to other HF medications. All patients tolerated ARNI without symptomatic or asymptomatic hypotension or worsening kidney function. High ARNI dose (97/103 mg) was achieved in three (17%) patients, and moderate (49/51 mg) in three (17%). At baseline, nine patients were NYHA FC 2, seven FC 3, and two FC 4. Mean baseline cardiopulmonary exercise testing (CPET) and echocardiographic data were: oxygen uptake (VO2) 18 mL/kg/min, minute ventilation/carbon dioxide (VE/VCO2) 38, right ventricular ejection fraction (RVEF) 32%, fractional area change (FAC) 21%. Significant tricuspid regurgitation was present in 33% (28% moderate, and 5% severe) and mean tricuspid annular plane systolic excursion (TAPSE) was 9.4 mm. With treatment, there was no statistically significant difference in blood pressure, labs, testing, or imaging. There was a statistically significant improvement in median NYHA FC (2 vs 2.5, p=0.005). When compared to an equal pre-ARNI median timeframe, there was a noted decrease in cardiac hospitalisation (4 vs 9) that did not reach statistical significance (p=0.313). CONCLUSION: In adult patients with failing systemic right ventricle, ARNI is safe and well tolerated. Their use is associated with improvement in functional status. Prospective studies on a larger group of patients are warranted to better understand the causes of this improvement.

Edge to edge repair using a MitraClip for severe tricuspid valve regurgitation after a Mustard operation.

A 48-year-old who underwent a Mustard operation in 1972 followed by a second cardiac intervention in 1996 for pulmonary venous baffle enlargement and residual baffle leak closure, complicated by recurrent atrial flutter, was admitted to our institution for severe systemic atrio-ventricular valve regurgitation (SAVVR) associated with severely impaired systemic right ventricular (RV) function. After careful preoperative anatomic assessment including three-dimensional transesophageal echocardiography (3DTEE) to define the clipping strategy and computed tomography to optimize the transvenous baffle puncture site, the intervention was performed under general anesthesia, fluoroscopic, and 3DTEE guidance. One XTR MitraClip was successfully implanted, achieving a significant reduction in regurgitation and immediate clinical improvement. The transbaffle puncture was closed using an 8 mm atrial septal defect (ASD) device without residual shunt or obstruction of the venous baffle. Post-operative clinical evaluation showed immediate improvement in the NYHA functional class (from III to II), but the patient presented with recurrent flutter at 1 week after the procedure, which was successfully treated by catheter ablation with another transbaffle approach next to the ASD device. Clinical improvement was maintained at 1- and 6-month follow-up with significant reduction in SAVVR, reduced systemic RV volumes and improved RV ejection fraction. This case demonstrates the feasibility of percutaneous treatment of systemic SAVV in patients with systemic RV after atrial redirection.

Medical Therapy for Systemic Right Ventricles: A Systematic Review (Part 1) for the 2018 AHA/ACC Guideline for the Management of Adults With Congenital Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines.

Patients with systemic morphological right ventricles (RVs), including congenitally corrected transposition of the great arteries and dextro-transposition of the great arteries with a Mustard or Senning atrial baffle repair, have a high likelihood of developing systemic ventricular dysfunction. Unfortunately, there are a limited number of clinical studies on the efficacy of medical therapy for systemic RV dysfunction. We performed a systematic review and meta-analysis to assess the effect of angiotensin-converting enzyme (ACE) inhibitors, angiotensin-receptor blockers (ARBs), beta blockers, and aldosterone antagonists in adults with systemic RVs. The inclusion criteria included age ≥18 years, systemic RVs, and at least 3 months of treatment with ACE inhibitor, ARB, beta blocker, or aldosterone antagonist. The outcomes included RV end-diastolic and end-systolic dimensions, RV ejection fraction, functional class, and exercise capacity. EMBASE, PubMed, and Cochrane databases were searched. The selected data were pooled and analyzed with the DerSimonian-Laird random-effects meta-analysis model. Between-study heterogeneity was assessed with Cochran's Q test. A Bayesian meta-analysis model was also used in the event that heterogeneity was low. Bias assessment was performed with the Newcastle-Ottawa Scale and Cochrane Risk of Bias Tool, and statistical risk of bias was assessed with Begg and Mazumdar's test and Egger's test. Six studies met the inclusion criteria, contributing a total of 187 patients; treatment with beta blocker was the intervention that could not be analyzed because of the small number of patients and diversity of outcomes reported. After at least 3 months of treatment with ACE inhibitors, ARBs, or aldosterone antagonists, there was no statistically significant change in mean ejection fraction, ventricular dimensions, or peak ventilatory equivalent of oxygen. The methodological quality of the majority of included studies was low, mainly because of a lack of a randomized and controlled design, small sample size, and incomplete follow-up. In conclusion, pooled results across the limited available studies did not provide conclusive evidence with regard to a beneficial effect of medical therapy in adults with systemic RV dysfunction. Randomized controlled trials or comparative-effectiveness studies that are sufficiently powered to demonstrate effect are needed to elucidate the efficacy of ACE inhibitors, ARBs, beta blockers, and aldosterone antagonists in patients with systemic RVs.

General principles of heart failure management in adult congenital heart disease.

The population of adults with congenital heart disease is now an estimated 1.4 million in the United States alone and growing. Unfortunately, survival to adulthood does not equate to a normal life expectancy, and heart failure (HF) has now emerged as the leading cause of death for the adult congenital heart disease (ACHD) patient. As this population continues to grow in number and advance in age, the prevalence of heart failure in the adult with congenital heart disease (ACHD-HF) will undoubtedly continue to increase. However, much of our current understanding of mechanism, diagnosis, and management of ACHD-HF remains limited. We aim to review the current understanding of the proposed definitions, mechanisms, clinical impact, and general management considerations of ACHD-HF while also recognizing the large number of knowledge gaps that persist.

Mechanisms for heart failure in systemic right ventricle.

There are two predominant scenarios where the right ventricle acts as the systemic ventricle, namely congenitally corrected transposition of the great arteries (CC-TGA) and patients with D-transposition of the great arteries (D-TGA) who have undergone an atrial switch operation. There is evidence that having a right ventricle in the systemic position predisposes to the development of heart failure. In this review, we aim to explore the proposed mechanisms and pathophysiology for heart failure in patients with a systemic right ventricle in these two subsets of patients.

Assessment and management of heart failure in the systemic right ventricle.

Transposition of the great arteries (TGA) is a common congenital cardiac malformation, in which many patients survive into adulthood. From the 1960s through much of the 1980s, the majority of those with D-TGA were repaired with an atrial switch procedure, in which the right ventricle (RV) remains the systemic ventricle. Congenitally corrected TGA patients often remain with a systemic RV. In these patients, heart failure risks result from residual sequelae of childhood repair, which often include tricuspid regurgitation, RV failure, and atrial and ventricular arrhythmias. Imaging techniques, including echocardiography, cardiac magnetic resonance imaging, multi-detector computed tomography, and radionuclide ventriculography focus on evaluation of anatomy and function as both diagnostic and prognostic tools. Biomarkers are used for risk stratification. Structural and surgical interventions are targeted for palliation and prevention of further decompensation in conjunction with pharmacologic, ablative, and device-based therapies for acute and chronic management of heart failure.

Ex vivo cardiovascular magnetic resonance diffusion weighted imaging in congenital heart disease, an insight into the microstructures of tetralogy of Fallot, biventricular and univentricular systemic right ventricle.

PURPOSE: Common types of congenital heart disease exhibit a variety of structural and functional variations which may be accompanied by changes in the myocardial microstructure. We aimed to compare myocardial architecture from magnetic resonance diffusion tensor imaging (DTI) in preserved pathology specimens. MATERIALS AND METHODS: Pathology specimens (n = 24) formalin-fixed for 40.8 ± 7.9 years comprised tetralogy of Fallot (TOF, n = 10), dextro-transposition of great arteries (D-TGA, n = 8) five with ventricular septal defect (VSD), systemic right ventricle (n = 4), situs inversus totalis (SIT, n = 1) and levo-TGA (L-TGA, n = 1). Specimens were imaged using a custom spin-echo sequence and segmented automatically according to tissue volume fraction. In each specimen T1, T2, fractional anisotropy, mean diffusivity, helix angle (HA) and sheet angle (E2A) were quantified. Pathologies were compared according to their HA gradient, HA asymmetry and E2A mean value in each myocardial segment (anterior, posterior, septal and lateral walls). RESULTS: TOF and D-TGA with VSD had decreased helix angle gradient by - 0.34°/% and remained symmetric in the septum in comparison to D-TGA without VSD. Helix angle range was decreased by 45°. It was associated with a decreased HA gradient in the right ventricular (RV) wall, i.e. predominant circumferential myocytes. The sheet angle in the septum of TOF was opposing those of the left ventricular (LV) free wall. Univentricular systemic RV had the lowest HA gradient (- 0.43°/%) and the highest HA asymmetry (75%). HA in SIT was linear, asymmetric, and reversed with a sign change at about 70% of the depth at mid-ventricle. In L-TGA with VSD, HA was asymmetric (90%) and its gradients were decreased in the septum, anterior and lateral wall. CONCLUSION: The organization of the myocytes as determined by DTI differs between TOF, D-TGA, L-TGA, systemic RV and SIT specimens. These differences in cardiac structure may further enlighten our understanding of cardiac function in these diverse congenital heart diseases.

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.

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.

Quantitative assessment of contractile reserve of systemic right ventricle in post-Senning children: Incorporating speckle-tracking strain and dobutamine stress echocardiography.

INTRODUCTION: The systemic load on the right ventricle (RV) after Senning atrial switch leads to ventricular dysfunction. Quantitative assessment of RV contractile reserve is mandatory to anticipate the need for anti-fibrotic treatment. We aimed to quantitatively assess RV contractile reserve in Senning children by estimating speckle-based global longitudinal strain (GLS) during dobutamine stress echocardiography (DSE). METHODS: This prospective study compared thirty-one post-Senning children (group I) and thirty controls (group II). In post-Senning children, echocardiographic RV systolic function using one-plane ejection fraction (RVEF), RV fractional area change (RVFAC), tricuspid annulus plane systolic excursion (TAPSE), its Z-score, and RVGLS were recorded at rest and peak DSE. Contractile reserve was defined as improvement >5% in RVEF, >2% in GLS, and/or to near normal TAPSE. RESULTS: RVEF, RVFAC, TAPSE, and TAPSE Z-score were significantly lower in patients than controls [RVEF:40.13 ± 2.93% vs 53.17 ± 3.17% (P < .001*), RVFAC: 21.17 ± 2.37% vs 37.23 ± 2.13% (P < .001*), TAPSE:13.81 ± 1.26 vs 17.45 ± 2.93 mm (P < .001*), TAPSE Z-score: -3.47 ± 0.46 vs -2.09 ± 0.48 (P < .001*)]. Also, RVGLS was significantly impaired in Senning children than controls[ (-11.89 ± 2.31% vs -22.35 ± 6.73% (P < .001*)]. At peak DSE, contractile reserve was not evident as measured by RVEF which increased none significantly to 42.47 ± 2.80% (P = .063). However, RVGLS improved significantly to -15.78 ± 0.93% (P < .001*) and discovered the masked contractile reserve in Senning children. The 19(61.29%) children who showed masked contractile reserve (improvement in RVGLS > 2%) underwent continuation of anti-fibrotic medications. CONCLUSIONS: Despite systemic RV function in post-Senning children was impaired at rest and during DSE, RVGLS was useful in quantitative assessment of masked contractile thus promoted continuing anti-fibrotic treatment.