Long-term outcome after the mustard repair for simple transposition of the great arteries. 28-year follow-up

Reoperations in Adolescents and Adults After Prior Arterial Switch Operation: The Society of Thoracic Surgeons Congenital Heart Surgery Database Analysis

BACKGROUND

Arterial switch operation (ASO) has supplanted physiologic repairs for transposition of the great arteries and related anomalies. As survival rates have increased, so has the potential need for cardiac reoperations to address ASO-related complications arising later in life.

METHODS

The Society of Thoracic Surgeons Congenital Heart Surgery Database (2010-2021) was reviewed to assess prevalence and types of cardiac reoperations for patients aged ≥10 years with prior ASO for transposition of the great arteries or double-outlet right ventricle/transposition of the great arteries type. A hierarchical stratification designating 13 procedure categories was established a priori by investigators. Each eligible surgical hospitalization was assigned to the single highest applicable hierarchical category. Outcomes were compared across procedure categories, excluding hospitalizations limited to pacemaker-only and mechanical circulatory support-only procedures. Variation during the study period in relative proportions of left heart vs non-left heart procedure category encounters was assessed.

RESULTS

There were 698 cardiac surgical hospitalizations for patients aged 10 to 35 years at 100 centers. The most common left heart procedure categories were aortic valve procedures (n = 146), aortic root procedures (n = 117), and coronary artery procedures (n = 40). Of 619 hospitalizations eligible for outcomes analysis, major complications occurred in 11% (67/619). Discharge mortality was 2.3% (14/619). Year-by-year analysis of surgical hospitalizations reveals substantial growth in numbers for the aggregate of all procedure categories. Growth in relative proportions of left heart vs non-left heart procedures was significant (P = .0029; Cochran-Armitage trend test).

CONCLUSIONS

This large multicenter study of post-ASO reoperations beyond early childhood documents year-over-year growth in total reoperations. Left-sided heart procedures recently had the highest rate of rise. These observations have implications for counseling, surveillance, and management.

Application of a modified clinical classification for pulmonary arterial hypertension associated with congenital heart disease in children: emphasis on atrial septal defects and transposition of the great arteries. An analysis from the TOPP registry

Aims

A proportion of patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) do not fit in the current classification. We aimed to analyse the applicability of an adapted clinical classification of PAH-CHD to pediatric patients using the TOPP-1 registry (Tracking Outcomes and Practice in Pediatric Pulmonary Hypertension) and focus on atrial septal defects (ASD) and transposition of the great arteries (TGA).

Methods and results

Hemodynamic and clinical data of all patients with PAH-CHD in the TOPP cohort were reviewed. Patients were classified according to predefined ABCDE categories (A: Eisenmenger syndrome, B: left-to-right shunt, C: coincidental defects, including all ASDs, D: corrected CHD, E: TGA), or as complex CHD (group 5), by 2 independent investigators. In case of disagreement, a third reviewer could either settle a final decision, or the patient was deemed not classifiable. Survival curves were calculated for each group and compared to idiopathic PAH patients of the registry. A total of 223 out of 531 patients in the registry had PAH-CHD, and 193 were categorized to the following groups: A 39(20%), B 27(14%), C 62(32%) including 43 ASDs, D 58(30%), E 7(4%), whereas 6 patients were categorized as group 5, and 10 patients were unable to be classified. No survival difference could be demonstrated between the groups.

Conclusions

This modified classification seems to be more applicable to pediatric PAH-CHD patients than the previous classification, but some patients with PAH-CHD who never had a shunt remain unclassifiable. The role of ASD in pediatric PH should be reconsidered.

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.

Cardiac MRI predictors of adverse outcomes in adults with a systemic right ventricle

Aims

Predicting risk in individuals with a systemic right ventricle (SRV) remains difficult. We assessed the value of cardiac MRI (CMR) for predicting death, heart transplantation (HT), or need for a ventricular assist device (VAD) in adults with D‐transposition of the great arteries (DTGA) post Mustard/Senning and in adults with congenitally corrected transposition of the great arteries (ccTGA) at two large academic centres.

Methods and results

Between December 1999 and November 2020, 158 adult patients with an SRV underwent CMR. Indexed right ventricular end‐diastolic volume (RVEDVI), indexed right ventricular end‐systolic volume (RVESVI), right ventricular ejection fraction (RVEF), and right ventricular mass (RV mass) were determined by a core laboratory. Receiver operating curves, area under the curve (AUC), and cut‐points maximizing sensitivity and specificity for the endpoint for each CMR parameter were calculated. Over a median of 8.5 years, 21 patients (13%) met a combined endpoint of HT referral, VAD, or death. Each CMR parameter was significantly associated with the endpoint in both cohorts. The AUCs for RVEDVI, RVESVI, RVEF, and RV mass to predict the endpoint were 0.93, 0.90, 0.73, and 0.84 for DTGA and 0.76, 0.74, 0.71, and 0.74 for ccTGA, respectively. Optimized cut‐points for RVEDVI were calculated for DTGA and ccTGA and were 132 and 126 mL/m², respectively. RVEDVI cut‐points were simplified to 130 mL/m² for survival analysis, which was significantly associated with survival in both cohorts.

Conclusions

Cardiac MRI parameters are associated with an increased risk of death, HT, or VAD in patients with an SRV and should be considered to facilitate risk stratification.

Echocardiographic differences between D-TGA and L-TGA in adult patients

Transposition of the great arteries (TGA) is a common cardiac malformation in which the great arteries are discordant relative to the ventricles. The two common forms of transposition include D-TGA, which presents with cyanosis early in life, and L-TGA, which on the other hand, may permit survival to adulthood without being diagnosed in childhood. There are remarkable differences between these two forms of TGA in the clinical presentation, echocardiographic findings, and long-term outcomes. Multimodality imaging in patients with TGA usually provides diagnostic and hemodynamic assessment for routine follow-up and preoperative planning prior to surgical or transcatheter intervention. In this review, we present a summary of the fundamental echocardiographic aspects of these two forms of TGA with emphasis in the adult congenital heart disease population.

Analysis of the 2020 European Society of Cardiology (ESC) Guidelines for the Management of Adults With Congenital Heart Disease (ACHD)

Adult congenital heart disease (ACHD) continues to rapidly increase worldwide. With an estimated 1.5 million adults with ACHD in the USA alone, there is a growing need for better education in the management of these complex patients and multiple knowledge gaps exist. This manuscript comprehensively reviewed the recent (2020) updated European Society of Cardiology Guidelines for the management of ACHD created by the Task Force for the management of adult congenital heart disease of the European Society of Cardiology, with perioperative implications for the adult cardiac anesthesiologist and intensivist who may be called upon to manage these complex patients.

Mechanical circulatory support as a bridge to candidacy in adults with transposition of the great arteries and a systemic right ventricle

OBJECTIVES

Clinical experience with continuous flow ventricular assist devices (VADs) in patients with transposition of the great arteries (TGA) including dextro-TGA and congenitally corrected TGA is rare, and indications as well as potential benefits or specific hurdles remain unclear. Therefore, our goal was to report on our experience regarding VAD therapy in adult patients with TGA as a bridge to candidacy.

METHODS

We performed a single-centre retrospective study of all adult patients with TGA with systemic right ventricular failure who had continuous flow VAD implants between 2010 and 2018. Study end points were all causes of death, major cardiac and cerebrovascular adverse events or pump thrombosis. Follow-up continued until the time of the heart transplant.

RESULTS

A total of 6 patients (4 men) had a continuous flow VAD implanted in the context of a failing systemic right ventricle (dextro-TGA after the Mustard procedure: n = 3; congenitally corrected TGA: n = 3). Demographics: mean age 32 ± 5.7 years; median Interagency Registry for Mechanically Assisted Circulatory Support: level II (range 1-4), mean pulmonary artery 48 ± 13 mmHg, mean pulmonary vascular resistance 5.6 ± 3.5 Wood units. Postoperative data: intensive care unit stay: 16 ± 9.7 days; in-hospital survival: 100%; no early VAD-related complications occurred. Mean follow-up: 33 ± 18 months; persistent left-side paresis: n = 1; minor (non-disabling) stroke: n = 2. Post-VAD pulmonary artery: 19 ± 3.4 mmHg; P < 0.005; post-VAD pulmonary resistance: 2.2 ± 0.55 Wood units; P = 0.066. Four patients had heart transplants after a mean waiting time of 30 months after the VAD was implanted; 2 patients are still on the waiting list (waiting time: 52 and 24 months).

CONCLUSIONS

Continuous flow VAD therapy is a feasible therapeutic option in adult patients with TGA and a failing systemic right ventricle as a bridge to candidacy and a bridge to a heart transplant.

Managing the Adult Patient with Congenital Heart Disease

The focus of this article is noncardiac surgery in the adult with congenital heart disease (CHD). The purpose is to provide the general and pediatric anesthesiologist with a basic overview of the most common congenital cardiac lesions, their long-term sequelae, and expected perioperative concerns during noncardiac surgery. Because of the very heterogeneous nature of CHD, it is difficult to make a single article a comprehensive guide for every lesion and its associated perioperative concerns. The authors hope to provide those who are not specifically trained in congenital cardiac anesthesia the basic principles and a greater understanding of each defect.

Paracorporeal Ventricular Assist Device Implantation in a Patient with Transposition of the Great Arteries After Senning Operation

We experienced a 33-year-old patient with D-looped transposition of the great arteries (D-TGA) and a history of Senning operation who was referred to our institute with cardiogenic shock and subsequently underwent urgent paracorporeal ventricular assist device (VAD) implantation, which was a first in Japan, that was eventually converted to a durable VAD. Central venous pressure was maintained relatively high to obtain VAD filling and recover end-organ dysfunction, given the migration of the inflow cannula due to rich trabeculae carneae of the anatomical right ventricle (systemic ventricle in this case).

Predictors of Late Mortality in D-Transposition of the Great Arteries After Atrial Switch Repair: Systematic Review and Meta-Analysis

Background

Existing data on predictors of late mortality and prevention of sudden cardiac death after atrial switch repair surgery for D‐transposition of the great arteries (D‐TGA) are heterogeneous and limited by statistical power.

Methods and Results

We conducted a systematic review and meta‐analysis of 29 observational studies, comprising 5035 patients, that reported mortality after atrial switch repair with a minimum follow‐up of 10 years. We also examined 4 additional studies comprising 105 patients who reported rates of implantable cardioverter‐defibrillator therapy in this population. Average survival dropped to 65% at 40 years after atrial switch repair, with sudden cardiac death accounting for 45% of all reported deaths. Mortality was significantly lower in cohorts that were more recent and operated on younger patients. Patient‐level risk factors for late mortality were history of supraventricular tachycardia (odds ratio [OR] 3.8, 95% CI 1.4–10.7), Mustard procedure compared with Senning (OR 2.9, 95% CI 1.9–4.5) and complex D‐TGA compared with simple D‐TGA (OR 4.4, 95% CI 2.2–8.8). Significant risk factors for sudden cardiac death were history of supraventricular tachycardia (OR 4.7, 95% CI 2.2–9.8), Mustard procedure (OR 2.2, 95% CI 1.1–4.1), and complex D‐TGA (OR 5.7, 95% CI 1.8–18.0). Out of a total 124 implantable cardioverter‐defibrillator discharges over 330 patient‐years in patients with implantable cardioverter‐defibrillators for primary prevention, only 8% were appropriate.

Conclusions

Patient‐level risk of both mortality and sudden cardiac death after atrial switch repair are significantly increased by history of supraventricular tachycardia, Mustard procedure, and complex D‐TGA. This knowledge may help refine current selection practices for primary prevention implantable cardioverter‐defibrillator implantation, given disproportionately high rates of inappropriate discharges.

Pregnancy Outcomes in Women After the Arterial Switch Operation

BACKGROUND

Pregnancy outcomes after the arterial switch operation (ASO) are rare. We sought to determine outcomes of ASO survivors who underwent pregnancy.

METHODS

Female patients who had an ASO and underwent pregnancy were identified from the congenital heart disease pregnancy clinic at The Royal Melbourne Hospital. All follow-up data were collected retrospectively by medical record review.

RESULTS

Eleven (11) women were identified as having undergone medical care during pregnancy, from the adult congenital database, at The Royal Melbourne Hospital. There were 17 successful pregnancies, and nine women have been followed post pregnancy. Of the 17 successful deliveries, eight were delivered by Caesarean section, seven were vaginal deliveries and two were instrumented vaginal deliveries. Of the eight Caesarean sections, five were emergency and three were elective. The indications for emergency Caesarean section were obstructed labour (n = 2), abnormal cardiotocography (n = 1), obstructed labour and abnormal cardiotocography (n = 1) and congestive cardiac failure (n = 1). There was one neonatal complication (respiratory distress requiring intubation) in a child born at 31 weeks. There were maternal obstetric complications in 10 patients. There were two maternal cardiac complications during pregnancy (heart failure and rapid atrial fibrillation/flutter). There was no change in left ventricular function post-pregnancy. There was progression of severity of neo-aortic valve regurgitation in two patients post pregnancy (trivial to mild and moderate-severe to severe respectively).

CONCLUSION

Pregnancy post ASO appears to be safe in the majority of women. Maternal cardiac complications are uncommon in patients without residual significant haemodynamic lesions, although maternal obstetric complications may be common.

Trans-apical systemic tricuspid valve-in-ring replacement

Transcatheter valve replacement offers a safe and effective alternative to traditional surgical techniques in patients with congenital heart disease, especially those at high surgical risk. The most common causes of morbidity and mortality in patients with D-transposition of the great arteries status post Senning or Mustard repair is severe tricuspid valve (TV) regurgitation. Replacement of the systemic TV may be useful in those without severe systemic ventricular dysfunction. We present a case of a patient with D-loop transposition of the great arteries status post Mustard repair and TV ring placement with subsequent severe systemic TV regurgitation, at high surgical risk, who underwent a transcatheter valve replacement via a trans-apical approach using an Edwards Sapien XT valve.

Natural history of a systemic right ventricle

The natural history of a systemic right ventricle after an atrial switch procedure has yet to be fully characterised. We describe the case of the longest surviving patient at our institution who underwent a Mustard Baffle correction for dextro-transposition of great arteries in childhood. Over following decades he was reviewed regularly with deteriorating systemic right ventricle function. At around 50 years of age he developed worsening heart failure on maximal medical therapy. He was subsequently assessed for cardiac transplantation which he underwent successfully at the age of 55 years.

Pulmonary arterial hypertension in adults with systemic right ventricles referred for cardiac transplantation

BACKGROUND

Systemic right ventricular (RV) failure may progress necessitating referral for orthotropic heart transplantation (OHT). Pulmonary hypertension (PH) frequently coexists in adult congenital heart disease and can complicate the assessment for OHT.

METHODS

Single-center case series of six patients (median age 34.9 years [IQR, 31.9-42.4]) with systemic RV physiology with PH referred for OHT evaluation from 2008 to 2017.

RESULTS

One-third (n = 6) of 18 patients with systemic RV physiology referred for OHT evaluation had pulmonary arterial hypertension (PAH) defined as mean pulmonary artery pressure (mPAP) > 25 mm Hg and pulmonary vascular resistance (PVR) > 3 Wood Units. Two of the six patients were considered OHT-ineligible due to PH and comorbidities. Of the remaining four, two had pre-capillary PH and underwent heart-lung transplant (HLTx). The other two demonstrated reversibility of PVR with vasodilator testing and underwent OHT alone, one of whom died post-transplant from PH crisis.

CONCLUSIONS

Pulmonary arterial hypertension is common in systemic RV patients referred for OHT. Systemic RV dysfunction places these patients at risk for post-capillary PH but pre-capillary PH can exist. Despite management with selective pulmonary vasodilators and afterload reduction, criteria for listing patients for HLTx vs OHT are not known and need further elucidation.

Longitudinal strain by two-dimensional speckle tracking to assess ventricular function in adults with transposition of the great arteries: Can serial assessment be simplified?

INTRODUCTION

Transposition of the great arteries (TGA) is a rare form of congenital heart disease in which most patients reach adulthood. Right ventricular dysfunction is the most severe residual complication in long-term follow-up, both in patients treated by atrial switch and in those with congenitally corrected TGA. New echocardiographic tools such as longitudinal strain by two-dimensional (2D) speckle tracking may improve assessment of ventricular function in these patients.

METHODS AND RESULTS

We performed a retrospective analysis of echocardiograms in adult patients with TGA (26 patients with dextro-TGA - 15 treated by atrial switch and six by arterial switch - and five with congenitally corrected TGA) and in a control group of 14 healthy individuals. Right ventricular strain was significantly worse (p<0.001), as was the corresponding annular plane systolic excursion (p=0.010) in atrial switch patients, in comparison to arterial switch patients, while no differences were found in left ventricular parameters. In the overall population, systemic right ventricular parameters were significantly less negative than pulmonary right ventricular parameters, and these were less negative than in controls. Left ventricular parameters were similar across groups, except for pulmonary left ventricular strain, which was worse than in controls (p=0.008) as well as pulmonary right ventricular strain.

CONCLUSIONS

Assessment of ventricular function in patients with TGA by 2D speckle tracking longitudinal strain is easy and feasible and may be a useful tool for serial follow-up. Of particular note, we found that there is also some degree of ventricular dysfunction even after re-establishment of normal connections.

Late-onset pulmonary arterial hypertension in repaired D-transposition of great arteries: an uncommon complication

Late-onset pulmonary arterial hypertension (PAH) is a rare but fatal complication in patients with childhood surgical repair of dextro-transposition of great arteries (D-TGA), especially with the Mustard and Senning procedures. The pathogenic mechanisms of PAH in patients with repaired D-TGA are not well understood and treatment is not standardized. In this manuscript, we present a case of late-onset PAH in an adult D-TGA patient after Mustard repair and discuss the pathogenic mechanisms, diagnosis, and treatment of pulmonary hypertension in repaired D-TGA.

Infective Endocarditis of the Systemic Venous Baffle Following the Atrial Switch Procedure in an Adult

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Central venous catheters may increase risk for infective endocarditis in patients with adult congenital heart disease.

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Transesophageal echocardiography may play a key role visualizing venous baffles after the atrial switch procedure.

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Percutaneous suction thrombectomy is an option in patients with shunts or baffles.

Stress Echocardiographic Evaluation for D-Transposition of the Great Arteries after Atrial Redirection: Unmasking Early Signs of Myocardial Dysfunction and Baffle Stenosis

BACKGROUND

The authors used semisupine cycle ergometry stress echocardiography to assess cardiac function and unmask baffle stenosis in patients with d-transposition of the great arteries after atrial redirection surgery.

METHODS

This was a retrospective review of semisupine cycle ergometry stress echocardiography performed in 53 patients (64% male; mean age, 24.0 years; 90% Mustard procedure) and 56 healthy control subjects. Incremental exercise to volitional fatigue was performed. Hemodynamic data, echocardiographic cardiac dimensions, area change, tissue Doppler velocities, strain, ventricular synchronization, and superior vena cava flow velocities before and immediately after exercise are reported.

RESULTS

Patients had lower exercise capacity (870 vs 1,854 J/kg, P < .001) and peak heart rates (132 vs 167 beats/min, P < .001). Stroke volume index did not increase with exercise (45 vs 47 mL/m², P = .400). Cardiac index increased in both groups with exercise (3.0 vs 6.1 and 2.9 vs 7.0 L/min/m², P < .001) and was higher in control subjects (P = .006). Right ventricular diastolic and systolic areas decreased significantly with exercise in both the short-axis and four-chamber views. Right and left ventricular contraction time shortened with exercise (405 vs 247 and 338 vs 217 msec, P < .001) and remained synchronous (ratio of right ventricular to left ventricular contraction time = 0.080). Doppler velocities in patients with baffle obstruction were higher in the lower superior vena cava with exercise compared with nonobstructed patients (1.87 vs 1.46 m/sec, P = .020) and normalized after catheter intervention (1.49 vs 1.46 m/sec, P = .800).

CONCLUSIONS

Patients with d-transposition of the great arteries have lower exercise capacity and peak heart rates. The systemic right ventricle presents a lesser but qualitatively normal systolic response and decreased diastolic filling. Semisupine cycle ergometry stress echocardiography unmasked SVC obstruction.

Arrhythmias Following the Mustard and Senning Operations for Dextro-Transposition of the Great Arteries: Clinical Aspects and Catheter Ablation

The atrial switch operations, the Mustard and Senning procedures, performed for dextro-transposition of the great arteries, have largely been supplanted by the arterial switch operation. As such, affected patients will only exist for approximately 30 more years. The main arrhythmias in these patients include sinoatrial node dysfunction, intraatrial reentry tachycardia, and sudden death. Device therapy for these patients is well-established, and catheter ablation for atrial tachycardias is highly efficacious. The application of meticulous procedural planning, customization of catheter courses, and electrophysiologic principles to this patient group may be extended to all postoperative complex congenital heart patients.

B-type natriuretic peptide: powerful predictor of end-stage chronic heart failure in individuals with systolic dysfunction of the systemic right ventricle

AIM

To assess whether B-type natriuretic peptide (BNP) can serve as a predictor of end-stage chronic heart failure (CHF) in patients with severe systolic dysfunction of the systemic right ventricle (SRV).

METHODS

We performed a retrospective analysis in 28 patients with severe systolic dysfunction of the SRV (ejection fraction 23 ± 6%) who were evaluated as heart transplant (HTx) candidates between May 2007 and October 2014. The primary endpoints of the study (end-stage CHF) were progressive CHF, urgent HTx, and ventricular assist device (VAD) implantation. Plasma BNP levels were measured using a chemiluminescent immunoassay.

RESULTS

During median follow-up of 29 months (interquartile range, 9-50), 3 patients died of progressive CHF, 5 patients required an urgent HTx, and 6 patients underwent VAD implantation. BNP was a strong predictor of end-stage CHF (hazard ratio per 100 ng/L: 1.079, 95% confidence interval, 1.042-1.117, P<0.001). The following variables with corresponding areas under the curve (AUC) were identified as the most significant predictors of end-stage CHF: BNP (AUC 1.00), New York Heart Association functional class class III or IV (AUC 0.98), decompensated CHF in the last year (AUC 0.96), and systolic dysfunction of the subpulmonal ventricle (AUC 0.96).

CONCLUSION

BNP is a powerful predictor of end-stage CHF in individuals with systolic dysfunction of the SRV.

Limited Ventricular Preload is the Main Reason for Reduced Stress Reserve After Atrial Baffle Repair

The atrial baffle repair (ABR) significantly improved the fate of patients with transposition of the great arteries (TGA). However, these patients show impaired exercise tolerance and some present severe decline of systemic ventricular function. Intrinsic myocardial weakness, low heart rate response to exercise and diastolic filling impairment are discussed to be causative. Forty-nine long-term survivors with TGA (median age 23.7 year) after ABR were catheterized with measured oxygen consumption in four conditions (baseline, volume, atrial pacing, dobutamine) and the results were compared to 10 normal controls. Median cardiac output was significantly lower in the ABR group (2.2 vs. 2.6 l/min/m²; p = 0.015), and systemic resistance was significantly elevated (28.9 vs. 22.2 U m²; p = 0.04) in comparison with normals. While stroke volume rose by 27% in the control group, it dropped by 7% in patients after ABR at atrial pacing (80/min). Stroke volume increase after dobutamine was significantly lower after ABR in comparison with normal controls (34 vs. 106%; p = 0.001). Higher NYHA class (p = 0.043), degree of tricuspid regurgitation (p = 0.009) and ventricular function (p = 0.028) were associated with lower stroke volume increase. Limited exercise capability of patients after ABR for TGA is primarily due to limited diastolic filling of the ventricles due to stiff non-compliant atrial pathways. Elevated systemic resistance may lead to severe myocardial hypertrophy with possible ischemia and contribute to the multifactorial decline of ventricular function in some patients.

[Arrhythmia in adults with congenital heart defects : Incidence, substrates, and mechanisms]

Arrhythmia management is one of the main challenges in the treatment of adult patients with congenital heart disease (ACHD). Apart from heart failure, arrhythmias are mainly responsible for morbidity and mortality in these patients. Supraventricular tachycardia is more frequent than ventricular arrhythmias and is not only associated with debilitating symptoms, but is often as threatening as ventricular tachycardia. The incidence depends on the underlying defect, type, and time of repair. For the overall ACHD population the incidence of supraventricular tachycardia is up to 50 % and increases with age and time since surgery. Arrhythmia substrate relates to structural abnormalities due to the congenital defect and most importantly to the amount of incisions and material used for repair. In addition, poor hemodynamic conditions influence substrate through dilatation, hypertrophy, and fibrosis. Both supraventricular and ventricular arrhythmias are due to a macroreentrant mechanism in the vast majority of patients, but focal arrhythmias occasionally occur as well.

Pulmonary Arterial Hypertension and Neonatal Arterial Switch Surgery for Correction of Transposition of the Great Arteries

INTRODUCTION AND OBJECTIVES

There are few reports of the appearance of pulmonary arterial hypertension following arterial switch surgery in the neonatal period to correct transposition of the great arteries. We assessed the frequency and clinical pattern of this complication in our series of patients.

METHODS

Our database was reviewed to select patients with transposition of the great arteries corrected by neonatal arterial switch at our hospital and who developed pulmonary hypertension over time.

RESULTS

We identified 2 (1.3%) patients with transposition of the great arteries successfully repaired in the first week of life who later experienced pulmonary arterial hypertension. The first patient was a 7-year-old girl diagnosed with severe pulmonary hypertension at age 8 months who did not respond to medical treatment and required lung transplantation. The anatomic pathology findings were consistent with severe pulmonary arterial hypertension. The second patient was a 24-month-old boy diagnosed with severe pulmonary hypertension at age 13 months who did not respond to medical therapy.

CONCLUSIONS

Pulmonary hypertension is a rare but very severe complication that should be investigated in all patients with transposition of the great arteries who have undergone neonatal arterial switch, in order to start early aggressive therapy for affected patients, given the poor therapeutic response and poor prognosis involved.

Mustard baffle obstruction and leak - How successful are percutaneous interventions in adults?

Atrial switch operations for D-Transposition of the great arteries (D-TGA) were performed until the late 20th century. These patients have substantial rates of re-operation, particularly for baffle related complications. This study sought to analyze the efficacy of percutaneous transcatheter intervention (PTI) for baffle leak and/or stenosis in adult atrial switch patients. Adult patients with a prior atrial switch operation who underwent heart catheterization (2002-2014) at a tertiary adult congenital heart disease referral center were retrospectively analyzed. In 58 adults (30 ± 8 years, 75% men, 14% New York Heart Association (NYHA) functional class ≥2) who underwent 79 catheterizations, PTI was attempted in 50 (baffle leak (n = 10, 20%), stenosis (n = 27, 54%), or both (n = 13, 26%)). PTI was successful in 45 and 5 were referred for surgery due to complex anatomy. A total of 40 bare metal stents, 18 covered stents, 16 occlusion devices, 2 angioplasties, and 1 endovascular graft were deployed. In isolated stenosis, there was improvement in NYHA functional class after PTI (8 vs. 0 patients were NYHA FC > 2, p = 0.004), which was matched by improvement in maximal oxygen consumption on exercise testing (VO₂) (25.1 ± 5.4 mL/kg/min vs. 27.9 ± 9 mL/kg/min, p = 0.03). There were no procedure-related deaths or emergent surgeries in this cohort. This single-center cohort is the largest reported series of adult atrial switch operation patients who have undergone PTI for baffle stenosis and/or leak. We demonstrate that PTI with an expert multi-disciplinary team is a safe and effective alternative to surgery in adult patients with an atrial switch operation.

Primary Prevention of Sudden Cardiac Death in Adults with Transposition of the Great Arteries: A Review of Implantable Cardioverter-Defibrillator Placement

Transposition of the great arteries encompasses a set of structural congenital cardiac lesions that has in common ventriculoarterial discordance. Primarily because of advances in medical and surgical care, an increasing number of children born with this anomaly are surviving into adulthood. Depending upon the subtype of lesion or the particular corrective surgery that the patient might have undergone, this group of adult congenital heart disease patients constitutes a relatively new population with unique medical sequelae. Among the more common and difficult to manage are cardiac arrhythmias and other sequelae that can lead to sudden cardiac death. To date, the question of whether implantable cardioverter-defibrillators should be placed in this cohort as a preventive measure to abort sudden death has largely gone unanswered. Therefore, we review the available literature surrounding this issue.

Dual-Chamber Stimulation with Single-Lead VDD Pacing System in Mustard Surgery

Sinus node disease is a problem encountered in patients after the Mustard surgery, requiring a pacemaker implantation. The knowledge of the complexity anatomy is crucial because of the possible challenges associated with this procedure. We report a case of a 24-year-old woman presented with symptomatic bradycardia, in which a bicameral stimulation using a single-lead VDD pacing system was successfully performed.

Eponymous cardiovascular surgeries for congenital heart diseases--imaging review and historical perspectives

Advances in pediatric cardiology and cardiac surgical techniques over the past few decades have revolutionized the management of the patients with congenital heart disease, and many now survive into adulthood. Several eponymous surgical procedures performed for congenital heart disease have been named after eminent surgeons. In this article, we provide a short biography of the surgeons associated with these eponymous surgical procedures along with their other important scientific contributions. This is followed by a review of these surgical procedures and their most common complications. Imaging appearances of these surgical procedures along with common complications are described and illustrated, with particular emphasis on magnetic resonance imaging. The surgical procedures described in this review include Blalock-Taussig, Potts, Waterston, Glenn, Fontan, Kawashima, Norwood, Sano, Damus-Kaye-Stansel, Mustard, Senning, Jatene, LeCompte, Rastelli, Rashkind, Ross, and Waldenhausen.

HeartWare Ventricular Assist Device Placement in a Patient With Corrected Dextro-Transposition of Great Arteries: A Case Report and Its Clinical Challenges

Given the improved survival in patients with corrected dextro-transposition of great arteries (D-TGA), it has evolved into an adult congenital heart defect. It is important to understand the management and complications observed in this population that eventually progresses to systemic ventricular failure requiring cardiac transplantation. Our case focuses on the rapid right ventricle (RV) deterioration of a patient with corrected D-TGA following a surgical procedure requiring systemic support. With such patients awaiting heart transplantation, there are limited assist devices available for RV support and no right ventricular assist device is approved for destination therapy yet. Current indications for implantation of the HeartWare ventricular assist device (HVAD) are limited by the Food and Drug Administration (FDA) to the left ventricle support as a bridge to transplantation. However, its use in the United States for right-sided support has rarely been described for adult congenital defects. In this case, a HeartWare assist device was used to provide systemic support as a bridge to cardiac transplant. The size and implantation design of the HVAD makes it a promising option for patients with this challenging patient population and RV failure as a late complication.

Implanting a Nonpulsatile Axial Flow Left Ventricular Assist Device as a Bridge to Transplant for Systemic Ventricular Failure After A Mustard Procedure

Right (systemic) ventricular failure is well described after a Mustard procedure for transposition of the great arteries. Sixty-one percent of patients have been reported to show moderate-to-severe dysfunction of the systemic ventricle, 25 years after repair of transposition of the great arteries by a Mustard procedure. In such cases, heart transplant often seems to be the only option. When severe heart failure with hemodynamic instability develops, the only way to bridge these patients to a transplant is implantation of a mechanical circulatory support system. Because of the special anatomic features of the right ventricle, the implantation procedure can be challenging. Here, we report the case of a patient who underwent a left ventricular assist device implant owing to severe heart failure, 36 years after undergoing a Mustard procedure.

Thirty-three years old modified senning operation

Numerous technical modifications and various complications of the Senning procedure have been described in the literature. We describe the excellent clinical status and anatomic result of a 33-year-old patient who underwent a modified Senning operation using the left atrial appendage for reconstruction more than 30 years prior to presentation.

Functional assessment for congenital heart disease

Significant improvement in survival of children with congenital cardiac malformations has resulted in an increasing population of adolescent and adult patients with congenital heart disease. Of the long-term cardiac problems, ventricular dysfunction remains an important issue of concern. Despite corrective or palliative repair of congenital heart lesions, the right ventricle, which may be the subpulmonary or systemic ventricular chamber, and the functional single ventricle are particularly vulnerable to functional impairment. Regular assessment of cardiac function constitutes an important aspect in the long-term follow up of patients with congenital heart disease. Echocardiography remains the most useful imaging modality for longitudinal monitoring of cardiac function. Conventional echocardiographic assessment has focused primarily on quantification of changes in ventricular size and blood flow velocities during the cardiac cycles. Advances in echocardiographic technologies including tissue Doppler imaging and speckle tracking echocardiography have enabled direct interrogation of myocardial deformation. In this review, the issues of ventricular dysfunction in congenital heart disease, conventional echocardiographic and novel myocardial deformation imaging techniques, and clinical applications of these techniques in the functional assessment of congenital heart disease are discussed.

Risk for sleep-disordered breathing in adults after atrial switch repairs for d-looped transposition of the great arteries

Although sleep-disordered breathing has been extensively studied in patients with left-ventricular dysfunction, little is known of its prevalence in adults with congenital heart disease. Patients with d-looped transposition of the great arteries (d-TGA) who have undergone atrial switch procedures often develop progressive heart failure. The objective of this study was to determine the prevalence of patients at risk for sleep-disordered breathing in adults with d-TGA and atrial switch procedures compared with a control population. Thirty-two patients with d-TGA (66 % males, median age 31) were compared with 32 healthy controls. Baseline demographics and clinical characteristics were documented. The snoring, tiredness during daytime, observed apnea, and high blood pressure (STOP) questionnaire was used to identify subjects at risk for obstructive sleep apnea (OSA). There was no difference in baseline demographics between subjects and controls. For the STOP questionnaire, 14 subjects with d-TGA had scores predictive of OSA compared with three in the control group (44 vs. 9 %, p = 0.0038). There was no difference in functional status between d-TGA patients with or without OSA. There is a greater prevalence of risk for sleep disordered breathing in adults with d-TGA compared with controls. Further prospective investigation with sleep studies will be valuable to confirm these findings.

Flow-sensitive four-dimensional velocity-encoded magnetic resonance imaging reveals abnormal blood flow patterns in the aorta and pulmonary trunk of patients with transposition

BACKGROUND AND OBJECTIVES

Flow profiles are important determinants of fluid-vessel wall interactions. The aim of this study was to assess blood flow profiles in the aorta and pulmonary trunk in patients with transposition and different ventriculoarterial connection, and hence different mechanics of the coherent pump.

METHODS

In all, 29 patients with operated transposition--concordant atrioventricular and discordant ventriculoarterial connection, and no other cardiac malformation--and eight healthy volunteers were assessed with cardiac magnetic resonance imaging: n = 17 patients after atrial redirection, with a morphologic right ventricle acting as systemic pump and a morphologic left ventricle connected to the pulmonary trunk, and n = 12 patients after the arterial switch procedure, with physiologic ventriculoarterial connections. Flow-sensitive four-dimensional velocity-encoded magnetic resonance imaging was used to analyse systolic flow patterns in the aorta and pulmonary trunk, relating to helical flow and vortex formation.

RESULTS

In the aorta, overall helicity was present in healthy volunteers, but it was absent in all patients independent on the operation technique. Partial helices were observed in the ascending aorta of 58% of patients after arterial switch. In the pulmonary trunk, mostly parallel flow was seen in healthy volunteers and in patients after arterial switch, whereas vortex formation was present in 88% of patients after atrial redirection.

CONCLUSION

Blood flow patterns differ substantially between the groups. In addition to varying mechanics of the coherent pumping ventricles, the absent overall helicity in all patients might be explained by the missing looping of the aorta in transposition.