Progressive aortic root dilatation in adults late after repair of tetralogy of Fallot

Management after childhood repair of tetralogy of fallot

The four characteristic findings in tetralogy of Fallot (TOF) include the following: 1) a malaligned ventricular septal defect; 2) right ventricular outflow and/or pulmonary valve/artery stenosis or atresia; 3) a dextraposed overriding aorta; and 4) right ventricular hypertrophy. This article focuses solely on the outcomes and treatment of surgically corrected patients born with TOF. In the modern era, early surgical repair consisting of ventricular septal defect closure and alleviation of right ventricular outflow obstruction have gained favor over early palliation with an aortopulmonary shunt followed by intracardiac repair. Surgical outcomes are excellent and dramatically improve prognosis. However, these patients are not "cured" and are at significant risk of developing subsequent electrical and hemodynamic problems. An operated patient with TOF should be evaluated at regular intervals by a cardiologist trained in congenital heart disease; any symptoms suggestive of hemodynamic or electrical compromise should spur further investigation. Advances in imaging, medical therapy, electrophysiology, device/resynchronization therapy, and percutaneous intervention provide the clinician with a number of therapeutic options. Surgical techniques have changed significantly since the early intracardiac repairs of the 1960s and 1970s. The deleterious hemodynamic and electrical effects of pulmonary regurgitation and ventriculotomy scars have spurred efforts to ensure pulmonary valvular competence and minimize the extent of ventricular incisions. Since Blalock and Taussig's first palliative shunt in 1945, the survival and quality of life for patients with TOF has improved dramatically; this is one of the great accomplishments for cardiovascular medicine in the 20th century. The 21st century promises further success with the advent of a myriad of technologic advancements.

The Team Approach to Pregnancy and Congenital Heart Disease

The successful pediatric management of congenital heart disease has resulted in increasing numbers of these patients in the reproductive age group and increasing clinical challenges for their physicians. These challenges can be met successfully, with improved results for mother and child, through a concerted comprehensive team approach that relies on a thorough understanding of the patient's underlying cardiac pathology and its anticipated interaction with the pregnancy, and ongoing close evaluation and communication with a team of trained and experienced specialist, including (but not limited to) cardiologist, obstetricians, anesthetists, pediatricians, clinical nurse specialists, and clinical geneticists. Such teams are not always available locally and it will be necessary to refer medium- and high-risk patients to a specialized tertiary care center.

Giant Aortic Aneurysm 18 Years After Repair of Double-Outlet Right Ventricle With Pulmonary Stenosis

Substantial long-term morbidity after a successful operation in complex congenital heart defects is a matter of concern. We present a patient with a giant ascending aortic aneurysm 18 years after repair of a double-outlet right ventricle with pulmonary stenosis. Our report emphasizes the need for ongoing follow-up into adulthood.

Surgery Insight: late complications following repair of tetralogy of Fallot and related surgical strategies for management

Biventricular correction of tetralogy of Fallot was devised more than 50 years ago. Current short-term outcomes are excellent. The potential for late complications is, however, an important concern for the growing number of postrepair survivors. Progressive pulmonary valve regurgitation leading to right heart failure and arrhythmia are centrally important problems faced by these patients. New techniques are, however, likely to change the future outcomes for postrepair survivors. These techniques include percutaneous valve replacement, arrhythmia ablation surgery, and strategies that emphasize preservation of the pulmonary valve even at the cost of leaving some residual valvular stenosis. The objectives of this Review are to outline the major complications that arise late after repair of tetralogy of Fallot, to describe the surgical approaches that have been developed to avoid and manage arising complications, and to briefly explore how novel treatment paradigms could change the future long-term outlook for patients following tetralogy repair.

Central and peripheral arterial stiffness in patients after surgical repair of tetralogy of Fallot: implications for aortic root dilatation

OBJECTIVES

To test the hypotheses that (1) the central conduit arteries stiffen preferentially over the peripheral conduit arteries in patients with repaired tetralogy of Fallot (ToF); and (2) central arterial stiffening is related to aortic root dilatation.

DESIGN AND PATIENTS

Heart-femoral pulse wave velocity (PWV), femoral-ankle PWV, carotid augmentation index and body surface area-adjusted aortic sinotubular dimension were determined in 31 children after ToF repair and compared with those in 31 age-matched controls after left-to-right shunt repair. In addition, the PWVs and augmentation index were related to the sinotubular junction dimension.

SETTINGS

Tertiary paediatric cardiac centre.

RESULTS

Compared with controls, patients had significantly greater heart-femoral PWV (mean 666 (SD 151) v 587 (81) cm/s, p = 0.021) and carotid augmentation index (-14.1 (17.0)% v -25.2 (14.6)%, p = 0.016), whereas the right (888 (202) v 845 (207) cm/s, p = 0.42) and left (918 (227) v 851 (215) cm/s, p = 0.25) femoral-ankle PWVs were similar between the two groups. The sinotubular junction z score of patients was significantly greater than that of controls (4.7 (1.5) v 1.1 (1.4), p < 0.001). Univariate analysis showed that the sinotubular junction z score correlated positively with heart-femoral PWV (r = 0.43, p = 0.001) and carotid augmentation index (r = 0.46, p = 0.001). Multiple linear regression similarly identified heart-femoral PWV (beta = 0.30, p = 0.04) and carotid augmentation index (beta = 0.31, p = 0.04) (model R(2) = 0.26) as significant determinants of sinotubular junction z score.

CONCLUSIONS

The aorta stiffens in patients with repaired ToF, which may contribute to progressive dilatation of the aortic root in the long term.

A comparison of magnetic resonance angiography with conventional angiography in the diagnosis of tetralogy of Fallot

AIMS

Our purpose was to assess the value of magnetic resonance angiography as a non-invasive alternative to catheterization in the evaluation of patients with tetralogy of Fallot, including those with pulmonary atresia.

METHODS AND RESULTS

We evaluated prospectively, using magnetic resonance angiography, 30 patients, aged from 1 to 18 years, 15 with tetralogy of Fallot and pulmonary stenosis, and 15 with pulmonary atresia. The studies obtained using magnetic resonance provided adequate visualization of the aorta, and provided excellent imaging of the pulmonary trunk and its right and left branches. Compared with catheterization, magnetic resonance had 100 percent sensitivity, specificity and accuracy for defining the presence or absence of the pulmonary arteries. Magnetic resonance also had 93.9 percent sensitivity, 98.2 percent specificity, and 96.7 percent accuracy for detection of stenosis or hypoplasia of the pulmonary arteries. We detected 25 major aortopulmonary collateral arteries with magnetic resonance, but only 22 with conventional angiography. There was complete agreement between the two methods in detecting patency of the arterial duct in 6 patients, and of Blalock-Taussig shunts in 12 patients.

CONCLUSION

Magnetic resonance angiography is a useful tool in the evaluation of patients with tetralogy of Fallot. It can be considered a non-invasive alternative to cardiac catheterization in the evaluation of the pulmonary vascular anatomy.

Aortic root dilation and aortic elastic properties in children after repair of tetralogy of Fallot

Analyses of aortic specimens obtained from patients with tetralogy of Fallot (TOF) revealed elastic fiber fragmentation. This study sought to determine the prevalence of aortic root dilation and aortic regurgitation (AR) in children after TOF repair and tested the hypothesis that aortic elastic properties are altered and related to aortic root dilation in these patients. Aortic dimensions, adjusted for body surface area and expressed as z scores, and AR were assessed echocardiographically in 67 children 8.3 +/- 5.6 years after TOF repair. The aortic elastic properties were compared with those in 50 age-matched controls. The prevalence of aortic dilation (z score >2) was 88%, 87%, 61%, and 63% at the annulus, sinus of Valsalva, sinotubular junction, and ascending aorta, respectively. The z scores of the annulus (r = 0.41, p <0.001) and sinus (r = 0.33, p <0.01) were correlated with body surface area. Multivariate analysis identified the duration of follow-up after surgery as the only significant determinant of z scores of the annulus (beta = 0.41, p = 0.001) and sinus (beta = 0.33, p = 0.009). AR was present in 12% of patients who tended to have larger z scores at all aortic levels. Compared with controls, patients had significantly increased aortic stiffness (p <0.001) and reduced strain (p <0.001) and distensibility (p = 0.002). Aortic stiffness was correlated positively, whereas aortic strain and distensibility were correlated negatively, with the aortic root z scores at all levels. In conclusion, this study shows a high prevalence of aortic root dilation in children after the repair of TOF. Aortic stiffening occurred in these patients and may play a role in progressive aortic root dilation.

Cardiovascular magnetic resonance in the follow-up of patients with corrected tetralogy of Fallot: a review

Cardiovascular magnetic resonance (CMR) is becoming an important tool in the clinical management of patients with congenital heart disease. Because of the diverse problems patients may face after initial correction for tetralogy of Fallot and the large amount of CMR techniques that can be applied, creating a patient-orientated imaging protocol is a difficult issue. Although it is still not certain what the impact of some parameters, provided by CMR, should be on clinical decision making, new techniques are being developed and applied. In this report, we review the current clinical issues in patients with tetralogy of Fallot and review the current implication and limitations of CMR in this patient category.

Report of the National Heart, Lung, and Blood Institute Working Group on Research in Adult Congenital Heart Disease

The Working Group on research in adult congenital heart disease (ACHD) was convened in September 2004 under the sponsorship of National Heart, Lung, and Blood Institute (NHLBI) and the Office of Rare Diseases, National Institutes of Health, Department of Health and Human Services, to make recommendations on research needs. The purpose of the Working Group was to advise the NHLBI on the current state of the science in ACHD and barriers to optimal clinical care, and to make specific recommendations for overcoming those barriers. The members of the Working Group were chosen to provide expert input on a broad range of research issues from both scientific and lay perspectives. The Working Group reviewed data on the epidemiology of ACHD, long-term outcomes of complex cardiovascular malformations, issues in assessing morphology and function with current imaging techniques, surgical and catheter-based interventions, management of related conditions including pregnancy and arrhythmias, quality of life, and informatics. After research and training barriers were discussed, the Working Group recommended outreach and educational programs for adults with congenital heart disease, a network of specialized adult congenital heart disease regional centers, technology development to support advances in imaging and modeling of abnormal structure and function, and a consensus on appropriate training for physicians to provide care for adults with congenital heart disease.

Hyperplastic Cellular Remodeling of the Media in Ascending Thoracic Aortic Aneurysms

Background— Progressive medial degeneration and atrophy is thought to be a cause of ascending thoracic aortic aneurysms in the elderly. Extensive apoptosis of vascular smooth muscle cells (VSMCs) has been demonstrated in the media of abdominal aortic aneurysms. We investigated whether medial atrophy from loss of VSMCs occurs in primary ascending thoracic aortic aneurysms.

Methods and Results— Morphometric analysis of 28 nonaneurysmal ascending thoracic aortas and 29 ascending thoracic aortic aneurysms was performed by directly measuring the thickness of their vascular layers and by indirectly calculating the area of their vascular compartments. The cellular and matrix composition of the media was assessed at the structural, protein, and transcript levels. Despite thinning of the media secondary to vascular dilatation, there was an overall increase in the medial area of aneurysms. VSMC density was preserved, implying cellular hyperplasia as a result of the increased medial mass. There was decreased expression of matrix proteins, despite sustained synthesis of these molecules, which was associated with evidence of increased matrix degradation. The remodeling and expansion of the media was most evident in comparisons between nonaneurysmal aortas versus smaller aneurysms and did not evolve further in larger aneurysms.

Conclusions— The mechanisms for luminal enlargement in thoracic and abdominal aortic aneurysms differ significantly with regard to the survival of VSMCs and atrophy of the media but share common pathophysiology involving degeneration of the matrix. Hyperplastic cellular remodeling of the media in ascending thoracic aortic aneurysms may be an initial adaptive response to minimize increased wall stress resulting from vascular dilatation.

Intrinsic histological abnormalities of aortic root and ascending aorta in tetralogy of Fallot: evidence of causative mechanism for aortic dilatation and aortopathy

BACKGROUND

Dilatation of the aortic root is a known feature in tetralogy of Fallot (TOF) patients with pulmonary stenosis (PS) or pulmonary atresia (PA). We hypothesized that intrinsic histological abnormalities of the aortic wall present since infancy are an important causative factor leading to aortic root dilatation.

METHODS AND RESULTS

We examined the aortic histology of 17 cases with TOF and PS/PA from our cardiac morphology archive and compared them with a control group of normal aortas. Measured circumference of the aortic root at the sinotubular junction and at the ascending aorta was indexed to the left ventricle. Aortic walls were studied by light microscopy with the use of various stains. Seventeen TOF cases (7 with PS, 10 with PA) including 7 infants, 2 children, and 8 adults were compared with 11 hearts with normal aorta. Aortic root circumference to left ventricular index and ascending aortic circumference to left ventricular index were 1.24+/-0.25 and 1.37+/-0.24, respectively, in the TOF group versus 0.89+/-0.10 and 0.88+/-0.11, respectively, in the control group (P<0.001). Histological changes of grade 2 or 3 were present in 29% (medionecrosis), 82% (fibrosis), 35% (cystic medial necrosis), and 59% (elastic fragmentation) in the ascending aorta of the TOF group. Histology grading scores were significantly higher in the TOF group (median score, 7; range, 1 to 12) compared with normal controls (median score, 2; range, 0 to 6) and correlated with the ascending aortic circumference to left ventricular index (r=0.525, P=0.03).

CONCLUSIONS

There are marked histological abnormalities in the aortic root and ascending aortic wall of patients with TOF present from infancy, suggesting a causative mechanism for subsequent aortic root dilatation.

Aortic root dilatation in tetralogy of Fallot long-term after repair—histology of the aorta in tetralogy of Fallot: evidence of intrinsic aortopathy

The ascending aorta or pulmonary trunk in congenital heart disease may dilate out of proportion to hemodynamic or morphogenetic expectations, may become aneurysmal, and may rupture. A bicuspid aortic valve and/or coarctation of the aorta are consistently associated with ascending aortic and para-coarctation medial abnormalities. Congenital heart diseases such as single ventricle, truncus arteriosus, transposition of the great arteries and tetralogy of Fallot are also associated with aortic medial abnormalities. Aortic regurgitation in unrepaired tetralogy of Fallot imposes volume overload on both ventricles. A significant subset of adults late after repair of tetralogy of Fallot exhibits progressive aortic root dilatation which may lead to regurgitation and predispose to dissection and rupture which can be fatal, and necessitating aortic valve and aortic root surgery. The aortic dilatation relates medial abnormalities coupled with previous long-standing volume overload of the ascending aorta. Risk factors for aortic dilatation and regurgitation in tetralogy of Fallot relate to specific hemodynamic abnormalities such as pulmonary atresia, right aortic arch and a history of an aorto-pulmonary shunt, and patient demographics such as male sex and the association of chromosome 22q11 deletion. There is no current consensus on beta-blocker administration for limiting progressive dilatation of the aortic root in patients with congenital heart disease and repaired tetralogy of Fallot. Aortic root surgery should be considered for these patients and address aortic regurgitation and or prevent the risk of aortic dissection. Meticulous follow-up of the aortic root after repair, tetralogy of Fallot are thus recommended.

Comparison of aortic stiffness in patients with juvenile forms of ascending aortic dilatation with versus without Marfan's syndrome

Aortic stiffness in 78 patients with juvenile forms of ascending aortic dilation with Marfan's syndrome was compared with aortic stiffness in 17 patients without Marfan's syndrome. In the ascending aorta and aortic arch, aortic stiffness was similarly increased in the 2 groups. In the descending aorta, however, aortic stiffness was increased only in patients with Marfan's syndrome.

Pulmonary regurgitation: not a benign lesion

Pulmonary regurgitation (PR) is a common complication after surgical or percutaneous relief of pulmonary stenosis and following repair of tetralogy of Fallot. Significant PR is usually well tolerated in childhood. However, in the long term, chronic PR has a detrimental effect on right ventricular (RV) function and exercise capacity and leads to an increased risk of arrhythmia and sudden cardiac death (SCD). Recent advances in non-invasive imaging and, in particular, wider availability of cardiovascular magnetic resonance (CMR), have improved the assessment of PR and RV function in these patients. This in turn has facilitated decision making on the optimal timing for elective pulmonary valve replacement (PVR), which should be performed before irreversible RV dysfunction ensues.

Aortic valve repair

Aortic valve replacement options are limited in children, and all of them have disadvantages. Aortic valve repair techniques have evolved slowly and have not gained wide acceptance; however, large series using a variety of techniques demonstrate that valve repair is possible with excellent early hemodynamics and satisfactory intermediate durability. The results of aortic valve repair at the Children's Hospital of Wisconsin are presented. Simple repairs (blunt valvotomy, commissurotomy, or commissurotomy with leaflet thinning) directed at congenital aortic stenosis resulted in 86% +/- 5% freedom from reintervention at 10 years. Repair of aortic insufficiency with ventricular septal defect (VSD) resulted in 93.3% +/- 6% freedom from reoperation at 10 years. Complex repairs included a combination of techniques and yielded 5-year freedom from reintervention of 83% +/- 7% compared with 73% +/- 11% for patients undergoing aortic valve replacement (P = .62). Aortic valve repair provides an alternative to aortic valve replacement in selected patients. The utility of aortic valve repair and aortic valve replacement must be measured not only in freedom from reintervention but also in regression of left ventricular mass and exercise testing. Improvement in outcome depends on better patient selection and suitable bioprosthetic materials.

Late outcomes in patients with surgically treated congenital heart disease

Optimizing late outcomes should be the end result of improvements in medical and surgical care for congenital heart disease (CHD). In addition to mortality, significant morbidities after surgery for CHD need to be considered. These include the need for reintervention, cardiovascular complications, exercise limitations, neurocognitive morbidities, effects on pregnancy, difficulty obtaining insurance, need for chronic medications, and impaired functional status and quality of life. Long-term outcome studies are difficult to perform, and their interpretation is complicated by intervening changes in management. Specific discussion of long-term follow-up of tetralogy of Fallot, D-transposition of the great arteries, and hypoplastic left heart syndrome illustrates the myriad management changes over the last three decades, the challenges in predicting outcomes for recent patients, and the need for ongoing initiation of long-term follow-up studies.

Late aortic root dilatation in tetralogy of Fallot may be prevented by early repair in infancy

The objectives of this study were to examine the relative contributions of development and hemodynamics in aortic root dilatation of tetralogy of Fallot, to assess the impact of systemic to pulmonary artery shunt on aortic annular size, and to seek any relationship between the timing of corrective surgery and subsequent aortic root size. We performed a retrospective analytical study at a tertiary referral center of M-mode and two-dimensionol aortic root measurements in children with tetralogy of Fallot prior to any surgical or palliative intervention, after insertion of a surgical shunt, and on intermediate and long-term follow-up post-repair. The main outcome measures were aortic root diameter prior to correction, after palliative shunt insertion, and after definitive repair. The study found that the aortic root is enlarged in unrepaired tetralogy of Fallot irrespective of age, increased in the first 3-6 months after palliative shunt surgery, and persisted into adulthood in those repaired after 1 year of age. Age-corrected aortic root dimensions normalized by mid-childhood in those who were repaired in infancy. Preexisting aortic root dilatation normalizes by 7 years of age in patients with tetralogy of Fallot who have been repaired in infancy, whereas it persists into adulthood in the group repaired post-infancy.

Avaliação pré e pós-operatória da tetralogia de Fallot por ressonância magnética

A proposta deste trabalho foi estudar, prospectivamente, por ressonância magnética (RM), pacientes com diagnóstico de tetralogia de Fallot e avaliar a validade da RM como exame pré e pós-operatório nesses pacientes. Foram estudados, através de seqüências spin-eco e angiografia por RM (angio-RM) com utilização de gadolínio, 20 pacientes com idades entre 1 e 29 anos. Onze pacientes apresentavam a forma clássica da tetralogia de Fallot e nove, a forma extrema (tetralogia de Fallot com atresia pulmonar). O estudo permitiu a avaliação adequada da aorta, possibilitando a análise quanto à presença ou não de dilatação e quanto à posição do arco aórtico em todos os casos. Houve também uma excelente visualização das artérias pulmonares principal, direita e esquerda, possibilitando a avaliação qualitativa quanto à presença de dilatação, hipoplasia, estenose, ou quanto à ausência do vaso. Os resultados obtidos indicam que a RM, incluindo técnicas de angio-RM com meio de contraste, é um método de grande utilidade no estudo pré e pós-operatório de pacientes com tetralogia de Fallot, porque permite a obtenção de informações anatômicas importantes e complementares à ecocardiografia, podendo ser considerada uma alternativa ao cateterismo cardíaco, principalmente na avaliação da anatomia vascular pulmonar.

Congenital heart disease in the adult: 2004

The number of newborn infants with congenital heart disease is relatively stable.However, because of marked advances in correction and palliation of these conditions,the great majority will survive into adult life, significantly increasing the number of such patients in our population. Most patients with congenital heart disease, treated or not,will require routine, continued medical observation and, therefore, many radiologists will become involved in their care. Not uncommonly, pertinent clinical information is not provided to the radiologist, particularly when the patient presents to an Emergency Room because of intercurrent disease. In order to interpret the chest film or CT examination and provide a pertinent report, the radiologist must be conversant with the patterns of the more common congenital cardiac anomalies as well as their post-operative appearances and potential complications.

Management of Adults with Operated Tetralogy of Fallot

All patients should have periodic review at an adult congenital heart center. A minimum of history taking, physical examination, electrocardiogram, and echocardiogram are required per visit. Further assessment of right ventricular size and function, preferably by cardiovascular magnetic resonance imaging, is advisable because it provides robust data on biventricular size and function. Exercise testing is a useful objective marker of functional capacity. Interval change in these parameters provides reliable guidance on the need for and the optimal timing of reintervention. These investigations should be considered as a baseline assessment for all patients and can be repeated with variable frequency depending on the severity of residual hemodynamic lesions. Treatment is based on an overall goal of preservation of biventricular function and risk modification for arrhythmia and sudden cardiac death.

Normal aortic dimensions and flow in 168 children and young adults

BACKGROUND

Knowledge of normal aortic dimensions is important while evaluating children with aortic root dilatation.

OBJECTIVE

The purpose of the study was to create normal values for aortic dimensions with two-dimensional echocardiography and for aortic flow velocities with Doppler echocardiography in healthy children and young adults.

DESIGN AND PATIENTS

One hundred and sixty-eight healthy children were studied by a single observer using digitized two-dimensional (2DE) and Doppler echocardiography.

METHODS

The 2DE measurements were obtained at the level of aortic annulus, sinus, sinotubular junction, before the origin of innominate artery, before and after the origin of left carotid artery, after left subclavian artery and descending aorta at the level of the diaphragm. Doppler measurements were made from ascending aorta and from descending aorta.

RESULTS

For the analysis the subjects were divided into five groups according to body surface area (BSA): 0.5-0.75 m2, 0.75-1.0 m2, 1.0-1.25 m2, 1.25-1.5 m2 and over 1.5 m2. Aortic dimensions normalized to BSA were greater in smaller children at all levels. All diameters correlated closely with age, BSA, height and weight (for each r>0.75, P<0.001). The best predictor of aortic dimensions was BSA with r values over 0.84 for all estimates (P<0.001). The diameters of ascending and descending aorta were similar in both genders when indexed to BSA. Flow velocities in descending aorta were greater than those measured in ascending aorta (P<0.001 for all measurements). There were significant inverse correlations with heart rate and velocity time integral in ascending and descending aorta (r=-0.32 and -0.53, P<0.001, respectively).

CONCLUSIONS

The presented aortic dimensions at eight levels from the valve annulus to the descending thoracic aorta by 2DE in conjunction with Doppler measurements of ascending and descending aorta in 168 healthy subjects will serve as reference data for further studies and clinical use in patients with various cardiac abnormalities.

Aortic dissection in pregnancy: analysis of risk factors and outcome

Aortic dissection during pregnancy is a life-threatening event. Recent studies have revealed similar histologic changes in the wall of the ascending aorta in patients with bicuspid aortic valve disease (BAVD). Based on a review of the literature, including the experience from two institutions, we looked at the patient's characteristics in patients with thoracic aortic dissection during pregnancy. We found that aortic root enlargement (> 4cm) or an increase of aortic root size during pregnancy in patients with BAVD, and Marfan syndrome is associated with a considerable risk for the occurrence of Type A dissection.