Long-Term Outcomes After Atrial Switch Operation for Transposition of the Great Arteries

Clinical Risk Assessment and Prediction in Congenital Heart Disease Across the Lifespan: JACC Scientific Statement

Congenital heart disease (CHD) comprises a range of structural anomalies, each with a unique natural history, evolving treatment strategies, and distinct long-term consequences. Current prediction models are challenged by generalizability, limited validation, and questionable application to extended follow-up periods. In this JACC Scientific Statement, we tackle the difficulty of risk measurement across the lifespan. We appraise current and future risk measurement frameworks and describe domains of risk specific to CHD. Risk of adverse outcomes varies with age, sex, genetics, era, socioeconomic status, behavior, and comorbidities as they evolve through the lifespan and across care settings. Emerging technologies and approaches promise to improve risk assessment, but there is also need for large, longitudinal, representative, prospective CHD cohorts with multidimensional data and consensus-driven methodologies to provide insight into time-varying risk. Communication of risk, particularly with patients and their families, poses a separate and equally important challenge, and best practices are reviewed.

External Validation of a Risk Score Model for Predicting Major Clinical Events in Adults After Atrial Switch

BACKGROUND

A risk model has been proposed to provide a patient individualized estimation of risk for major clinical events (heart failure events, ventricular arrhythmia, all-cause mortality) in patients with transposition of the great arteries and atrial switch surgery. We aimed to externally validate the model.

METHODS AND RESULTS

A retrospective, multicentric, longitudinal cohort of 417 patients with transposition of the great arteries (median age, 24 years at baseline [interquartile range, 18-30]; 63% men) independent of the model development and internal validation cohort was studied. The performance of the prediction model in predicting risk at 5 years was assessed, and additional predictors of major clinical events were evaluated separately in our cohort. Twenty-five patients (5.9%) met the major clinical events end point within 5 years. Model validation showed good discrimination between high and low 5-year risk patients (Harrell C index of 0.73 [95% CI, 0.65-0.81]) but tended to overestimate this risk (calibration slope of 0.20 [95% CI, 0.03-0.36]). In our population, the strongest independent predictors of major clinical events were a history of heart failure and at least mild impairment of the subpulmonary left ventricle function.

CONCLUSIONS

We reported the first external validation of a major clinical events risk model in a large cohort of adults with transposition of the great arteries. The model allows for distinguishing patients at low risk from those at intermediate to high risk. Previous episode of heart failure and subpulmonary left ventricle dysfunction appear to be key markers in the prognosis of patients. Further optimizing risk models are needed to individualize risk predictions in patients with transposition of the great arteries.

Biventricular performance in adults with a systemic right ventricle: new insights from myocardial work analysis

To evaluate biventricular mechanics by means of echo-derived myocardial work (MW) analysis in patients with a systemic right ventricle (sRV). Comprehensive echo data were collected in all patients with a sRV who underwent transthoracic echocardiography at our tertiary centre between 2020 and 2021 including sRV function indices, global longitudinal strain (GLS) of right and left ventricle (RV/LV), biventricular MW, and atrial strain in those with congenitally corrected transposition of the great arteries (ccTGA). Fifty-six patients (37 [30.97-45.87]years, 59% male) and 49 healthy individuals matched per age and sex were included for comparison. Global work index (GWI:1106 [869.80-1293.10] Vs 314.2 [281.5-358.2]mmHg%, p < 0.0001) and global constructive work(GCW: 1542.50 [1338.9-1718.50] Vs 416.4 [365.70-464]mmHg%, p < 0.0001) were both increased for sRV compared to normal RV, reflecting exposition to a systemic afterload, with a contemporary raise in wasted work (GWW:197 [138.50-322.20] Vs 26.09 [17.80-43.48]mmHg%, p < 0.0001) and impaired efficiency (GWE:89 [83-93.54] Vs 93.67 [91.67-96] %, p < 0.0001). Conversely, sRV showed reduced MW indices in comparison to normal LV(p < 0.0001 for all). Non-systemic LV demonstrated normal GLS values (19.51 ± 3.9%), but reduced GWI (479 [368-665] Vs 2172 [1978-2386]mmHg%, p < 0.0001) and GCW (708 [490-815]mmHg% Vs 86.5 [59.25-118], p < 0.0001). Nevertherless, non-systemic LV showed also impaired efficiency (91 [88-94] Vs 95 [94-97]%, p < 0.0001). LVGLS values were related to RVGLS (R = 0.5, p = 0.00019), suggesting a consistent interventricular dependency. Atrial strain could be assessed in 16 out of 20 (80%) patients with ccTGA: both atria had reduced strain values compared to their normal counterparts. Moreover, pulmonary atrial strain during the reservoir phase was related to LVGWE (R = 0.58, p = 0.047) and inversely related to LVGLS (R = - 0.71, p = 0.0043). MW analysis is feasible in sRV and may provide additional clinical data. In our cohort MW revealed biventricular impairment, in particular for non-systemic LV, in spite of normal GLS values.

Arrhythmias in Adult Congenital Heart Disease Heart Failure

Heart failure and arrhythmias represent 2 major causes of mortality and morbidity in adults with congenital heart disease. Arrhythmias and heart failure are interdependent, and one may exacerbate the other. Treatment of one also has a positive impact on the other. Management approaches need to be multifaceted, including pharmacotherapy, optimization of hemodynamic status with catheter-based or surgical interventions, and specific management of arrhythmia with device or catheter ablation therapy.

The Role of Multimodality Imaging in the Evaluation of Heart Failure and Surgical Transplant Planning of Patients with Adult Congenital Heart Disease

Cardiac imaging is pivotal in evaluating ventricular function, residual lesions, and long-term complications in patients with adult congenital heart disease (ACHD). Longitudinal imaging in ACHD is key for the timely identification of patients requiring evaluation for advanced therapies. The guidelines recommend routine imaging surveillance. In all patients undergoing evaluation with cardiac imaging, it is critical that studies are performed at centers with expertise and that the imaging protocols are tailored to the specific condition. The authors briefly highlight the utility and diagnostic yield of different modalities, review pertinent considerations for special populations, and focus on imaging for transplant planning.

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.

Myocardial work of the systemic right ventricle and its association with outcomes

We aimed to evaluate clinical and prognostic significance of myocardial work parameters of the systemic right ventricle (SRV). Thirty-eight patients with the SRV underwent echocardiographic assessment of the SRV systolic function including 3D-echocardiography derived ejection fraction, 2D longitudinal strain and myocardial work analysis. The study endpoint was the combination of all-cause mortality and heart transplantation. Global constructive work (GCW) and global work index (GWI) demonstrated moderate correlation with the 3DE-derived SRV ejection fraction (EF) (Rho 0.64, p < 0.0001 and Rho 0.63, p < 0.0001, respectively). GCW showed the strongest correlation with the BNP level (Rho - 0.77, p < 0.0001), closely followed by GWI, 4-chamber longitudinal strain and 3DE EF (all Rho - 0.73, p < 0.0001). GCW and GWI were significantly lower in patients with moderate or severe tricuspid regurgitation compared with less than moderate regurgitation (1226 ± 439 vs 1509 ± 264 mmHg%, p = 0.02, and 984 ± 348 vs 1259 ± 278 mmHg%, p = 0.01, respectively). During a follow-up of 3.5 (2.8-3.9) years, seven patients (18%) died and one received transplantation (3%). They had significantly lower GCW and GWI compared with patients who did not reach the study endpoint (908 ± 255 vs 1433 ± %, p < 0.001 and 721 ± 210 vs 1173 ± 315 mmHg%, p < 0.001, respectively). In Cox regression analysis, GCW, GWI, 3DE SRV volumes and EF were the best-fit models based on the Akaike Information Criterion, outperforming longitudinal strain parameters. GWI and GCW, novel echocardiographic parameters of myocardial work, provided reliable quantification of the SRV systolic function. GWI, GCW and 3DE-derived SRV parameters were closely associated with all-cause mortality and heart transplantation in patients with the SRV.

Prognostic significance of subpulmonary left ventricular size and function in patients with a systemic right ventricle

AIMS

To assess the additional prognostic significance of echocardiographic parameters of subpulmonary left ventricular (LV) size and function in patients with a systemic right ventricle (SRV).

METHODS AND RESULTS

All adults with an SRV who underwent transthoracic echocardiography in 2010-18 at a large tertiary centre were identified. Biventricular size and function were assessed at the most recent examination. The study endpoint was all-cause mortality or heart/heart-lung transplantation. We included 180 patients, with 100 (55.6%) males, with a mean age of 42.4 ± 12.3 years, of whom 103 (57.2%) had undergone Mustard/Senning operations and 77 (42.8%) had congenitally corrected transposition of great arteries. Over 4.9 (3.8-5.7) years, 28 (15.6%) patients died and 4 (2.2%) underwent heart or heart-lung transplantation. Univariable predictors of the study endpoint included age, New York Heart Association functional Class III or IV, history of atrial arrhythmias, presence of a pacemaker or cardioverter defibrillator, high B-type natriuretic peptide, and echocardiographic markers of SRV and subpulmonary LV size and function. On multivariable Cox analysis of echocardiographic variables, indexed LV end-systolic diameter [ESDi; hazard ratio (HR) 2.77 (95% confidence interval, CI) 1.35-5.68, P = 0.01], LV fractional area change [FAC; HR 0.7 (95% CI 0.57-0.85), P = 0.002), SRV basal diameter [HR 1.66 (95% CI 1.21-2.29), P = 0.005], and SRV FAC [HR 0.65 (95% CI 0.49-0.87), P = 0.008] remained predictive of mortality or transplantation. On receiver-operating characteristic analysis, subpulmonary LV parameters performed better than SRV markers in predicting adverse events.

CONCLUSION

SRV basal diameter, SRV FAC, LV ESDi, and LV FAC are significantly and independently associated with mortality and transplantation in adults with an SRV. Accurate echocardiographic assessment of both SRV and subpulmonary LV is, therefore, essential to inform risk stratification and management.

Fate After the Mustard Procedure for d-Transposition of the Great Arteries: Impact of Age, Complexity, and Atrial Tachyarrhythmias: A Single Center Experience

Patients with dextro transposition of the great arteries (d-TGA) after atrial switch procedure are at risk to develop heart failure and arrhythmias during long-term follow-up. The present study aims to add knowledge on the fate of subjects after Mustard procedure during long-term follow-up into adulthood. A single center, retrospective chart review analysis was conducted. All subjects who had Mustard-type atrial switch procedure between 1969 and 1994 at our institution were included. A total of 92 subjects were included. Early postoperative death was reported in 2 subjects. Long-term follow-up was available in 49 survivors. Of those, 6 individuals died during further follow-up. Sudden cardiac death was the most prevalent cause for fatal outcome. Mortality during long-term follow-up was associated with the presence of additional cardiovascular malformations (complex d-TGA). Sinus node dysfunction was observed in 65% of the patients and atrial tachyarrhythmias were common in adult survivors (63%). Implantation of a pacemaker or a cardioverter defibrillator was required in 31% and 45% of those surviving into adulthood. Complications were frequently observed during follow-up after either pacemaker or cardioverter defibrillator implantation (43%) with lead failure being the most frequent complication. The aging population of patients after Mustard procedure is facing challenging problems mainly resulting from a failing systemic right ventricle, presence of associated cardiac malformations and the presence of atrial baffles associated with relevant atrial scars. Age, associated cardiac malformations, and atrial tachyarrhythmias seem to play a major role in determining the fate of patients with d-TGA after atrial switch procedures.

Ventricular Arrhythmias in Adults With Congenital Heart Disease, Part II: JACC State-of-the-Art Review

There are marked variations in the incidence of sudden cardiac death (SCD) and in the substrates for ventricular arrhythmias (VAs) across the gamut of congenital heart defects. In this 2-part review, patients with higher-risk forms of congenital heart disease (CHD) were conceptually categorized into those with discrete anatomic isthmuses for macro-reentrant ventricular tachycardia (VT) (Group A) and those with more diffuse or less well-defined substrates (Group B) that include patchy or extensive myocardial fibrosis. The latter category encompasses CHD lesions such as Ebstein anomaly, transposition of the great arteries with a systemic right ventricle (RV), and congenital aortic stenosis. For Group B patients, polymorphic VT and ventricular fibrillation account for a higher proportion of VA. The prognostic value of programmed ventricular stimulation is less well established, and catheter ablation plays a less prominent role. As cardiomyopathies evolve over time, pathophysiological mechanisms for VA among Groups A and B become increasingly blurred.

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.

Tricuspid valve replacement provides better long-term survival and tricuspid valve function than repair in patients with systemic right ventricle

Objective

The purpose of this study is to compare the long-term outcomes of 2 different tricuspid surgeries including valvuloplasty and replacement for significant tricuspid regurgitation in patients with systemic right ventricle.

Method

This is a retrospective study of 34 patients with dextro-transposition of the great arteries or levo-transposition of the great arteries with biventricular circulation and systemic right ventricle undergoing tricuspid valve surgery between April 1979 and April 2022. Patients were divided into 2 groups based on the procedure: tricuspid valvuloplasty (n = 11) and tricuspid valve replacement (n = 23). These groups were compared in terms of survival, tricuspid valve dysfunction, and tricuspid valve-related reoperation.

Results

There was no significant difference between the groups in operative age, body weight, the proportion of dextro-transposition of the great arteries, Ebstein-like tricuspid dysplasia, and preoperative right ventricular volume/function. During the median follow-up of 9.7 years, there was 1 early death (tricuspid valvuloplasty group) and 4 late deaths (3 in tricuspid valvuloplasty group and 1 in tricuspid valve replacement group). There were 7 tricuspid valve dysfunctions, including 6 significant tricuspid regurgitations in the tricuspid valvuloplasty group and 1 prosthetic valve dysfunction in the tricuspid valve replacement group, and 4 tricuspid valve-related reoperations (3 in the tricuspid valvuloplasty group and 1 in the tricuspid valve replacement group) were performed. There were significant differences between the groups in survival (tricuspid valvuloplasty vs tricuspid valve replacement: 72.7 vs 94.7% at 10 years after surgery, P = .0328) and cumulative incidence of tricuspid valve dysfunction at 10 years after tricuspid surgery (tricuspid valvuloplasty vs tricuspid valve replacement: 27.3% vs 0%, P = .0121).

Conclusions

Tricuspid valve replacement provided better long-term survival and tricuspid function in patients with systemic right ventricle compared with tricuspid valvuloplasty.

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.

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.

Cardiac Drugs in ACHD Cardiovascular Medicine

Adult congenital heart disease (ACHD) is a growing population that requires life-long care due to advances in pediatric care and surgical or catheter procedures. Despite this, drug therapy in ACHD remains largely empiric due to the lack of clinical data, and formalized guidelines on drug therapy are currently lacking. The aging ACHD population has led to an increase in late cardiovascular complications such as heart failure, arrhythmias, and pulmonary hypertension. Pharmacotherapy, with few exceptions, in ACHD is largely supportive, whereas significant structural abnormalities usually require interventional, surgical, or percutaneous treatment. Recent advances in ACHD have prolonged survival for these patients, but further research is needed to determine the most effective treatment options for these patients. A better understanding of the use of cardiac drugs in ACHD patients could lead to improved treatment outcomes and a better quality of life for these patients. This review aims to provide an overview of the current status of cardiac drugs in ACHD cardiovascular medicine, including the rationale, limited current evidence, and knowledge gaps in this growing area.

Heart failure in systemic right ventricle: Mechanisms and therapeutic options

d-loop transposition of the great arteries (d-TGA) and congenitally corrected transposition of the great arteries (cc-TGA) feature a right ventricle attempting to sustain the systemic circulation. A systemic right ventricle (sRV) cannot support cardiac output in the long run, eventually decompensating and causing heart failure. The burden of d-TGA patients with previous atrial switch repair and cc-TGA patients with heart failure will only increase in the coming years due to the aging adult congenital heart disease population and improvements in the management of advanced heart failure. Clinical data still lags behind in developing evidence-based guidelines for risk stratification and management of sRV patients, and clinical trials for heart failure in these patients are underrepresented. Recent studies have provided foundational data for the commencement of robust clinical trials in d-TGA and cc-TGA patients. Further insights into the multifactorial nature of sRV failure can only be provided by the results of such studies. This review discusses the mechanisms of heart failure in sRV patients with biventricular circulation and how these mediators may be targeted clinically to alleviate sRV failure.

SCUBA Diving in Adult Congenital Heart Disease

Conventionally, scuba diving has been discouraged for adult patients with congenital heart disease (ACHD). This restrictive sports advice is based on expert opinion in the absence of high-quality diving-specific studies. However, as survival and quality of life in congenital heart disease (CHD) patients have dramatically improved in the last decades, a critical appraisal whether such restrictive sports advice is still applicable is warranted. In this review, the cardiovascular effects of diving are described and a framework for the work-up for ACHD patients wishing to engage in scuba diving is provided. In addition, diving recommendations for specific CHD diagnostic groups are proposed.