Search

The palliation of the cyanotic child with a dominant morphologically left ventricle, discordant ventriculo-arterial connections, and obstruction to the pulmonary outflow tract has continued to evolve and mature. The evolution began in the early days of surgical palliation with the Blalock-Taussig shunt, extended to construction of cavopulmonary shunts, if required, and then to the Fontan procedure and its subsequent modifications. This journey took nearly 30 years to complete. There is increasing clinical data to document the beneficial effects of this approach, with ever-improving outcomes. Some aspects of the history of the cavopulmonary shunt have been previously reviewed in this journal and elsewhere, as have analysis of outcomes for some groups of patients considered for surgical completion of the Fontan circulation. While there has been some ongoing interest in ventricular septation since the early success of Sakakibara et al., this approach has largely been abandoned. Considerably more challenges and debate resonate in the surgical algorithms defined for patients whose hearts are characterized by a dominant left ventricle, discordant ventriculo-arterial connections, and unobstructed flow of blood to the lungs. This latter group will be the focus of this review, as will the aetiology of the myocardial hypertrophy that is particularly frequent in this group of patients, its clinical recognition, indeed its anticipation, and the multiple surgical strategies designed to prevent or treat it. All these manoeuvres are considered to optimise suitability for, and outcome from, creation of the Fontan circulation.

An aortopulmonary window is a communication between the ascending aorta and pulmonary trunk in the presence of two separate arterial valves, and is often complicated by other associated defects. We sought to determine management and related outcomes in patients with this malformation. We identified those patients presenting between 1969 and 1999 from the databases held in our Departments of Cardiology, Pathology and Cardiovascular Surgery. We obtained data relating to issues concerning demography, clinical findings, imaging, management and outcome. The median age at presentation for the 42 patients identified, of whom 23 were female, was 62 days, with a range from birth to 6 years. Associated cardiac defects were present in 34 patients, including interruption of the aortic arch in 6 patients. The correct diagnosis was initially missed in 13 patients. Of the patients, six died without surgical repair, and 1 patient was lost-to-follow-up. Repair was performed in 35 patients, subsequent to repair of other defects in 4, in association with repair of other defects in 17, of whom 3 died, and as an isolated procedure in 14 patients, one of the latter being treated by transcatheter closure. Overall, there were 9 deaths, all in patients with complex associated defects, except 1 patient with a missed aortopulmonary window after repair of aortic coarctation. Kaplan-Meier estimates of survival were 81% at 3 months until 11.5 years, and 69% up to 21 years. Only the presence of interrupted aortic arch was independently associated with increased time-related mortality, the hazard ratio being 5.87 (p = 0.009). The outcome for an isolated lesion is excellent. Mortality occurs mainly before repair, mostly with complex associated lesions, particularly interruption of the aortic arch.

Pulmonary arteriovenous fistulas are vascular malformations, which, by virtue of producing abnormal vascular connections proximal to the units of gas exchange, result in intrapulmonary right-to-left shunting. These malformations or fistulas reflect at least in part disordered angiogenesis, and less commonly recruitment and dilation of pre-existing vascular channels. Pulmonary arteriovenous fistulas occur in a number of diverse clinical settings. Such fistulas are a well-established feature of the Weber-Osler-Rendu complex, or hereditary haemorrhagic telangiectasia, an autosomal dominant vascular dysplasia characterized by mucocutaneous telangiectasis, epistaxis, gastrointestinal haemorrhage, and arteriovenous malformations in the lung, brain, liver and elsewhere. They are also seen in the patient with acute or chronic liver disease, disease that is usually but not invariably severe, or those with non-cirrhotic portal hypertension. They may occur as congenital malformations, single or diffuse, large or small in isolation, and when large or extensive enough may result in hypoxaemia, clinical cyanosis, and heart failure. Cerebral vascular accidents are also a well-known complication of this disorder. An extensive literature has accumulated with regard to the pulmonary arteriovenous fistulas seen in the setting of the Weber-Osler-Rendu complex, and there is considerable information on the genetics, basic biology, clinical findings, complications and therapeutic interventions of these malformations in the setting of this syndrome. These issues, however, are not the primary considerations of this review, although some aspects of this fascinating disorder will be discussed later. Rather the focus will be on pulmonary arteriovenous malformations that develop in the setting of cavopulmonary surgery, and their relationship to the pulmonary arteriovenous fistulas occurring in the hepatopulmonary syndrome. The complex tapestry of these overlapping and intersecting clinical observations will be unfolded in the light of their chronology.

Objectives: We sought to determine trends, and outcomes, for a cohort of patients with pulmonary atresia with intact ventricular septum born between 1965 and 1998., Background: Pulmonary atresia with intact ventricular septum is a complex lesion that remains a therapeutic challenge, particularly regarding the suitability for biventricular repair., Methods: We identified 210 consecutive patients, and reviewed their medical records, initial angiograms, and echocardiograms, along with the relevant surgical and pathology reports., Results: The mean initial Z-score for the diameter of the tricuspid valve was -0.99 +/- 1.95, with Ebstein's malformation in 8%. A right ventricular dependent coronary arterial circulation was found in 23%. The proportion of patients who received treatment increased over time, although placement of an arterial shunt was the predominant initial procedure throughout the experience. At the last follow-up, 107 patients had not reached the planned final stage of their repair, and 79% of these had died. Of the 103 reaching the final stage of planned repair, 58 had undergone attempted biventricular repair, with 34% dying; 14 had undergone attempted one and a half ventricular repair, with 7% dying, and 31 had undergone attempted functionally univentricular repair, with 10% dying. Overall, survival was 57% at the age of 1 year, 48% at 5 years, and 43% at 10 years. Survival improved over time, with survival of 75% at 1 year, and 67% at 5 years, for patients born between 1992 and 1998. An earlier date of birth, the presence of Ebstein's malformation, and prematurity were all significant independent factors associated with decreased survival. A greater severity of coronary arterial abnormalities was significantly associated with a greater likelihood of left ventricular dysfunction during follow-up., Conclusions: The outcomes for patients born with pulmonary atresia with intact ventricular septum have improved over time, albeit that careful initial management, and better selection, is still indicated for those planned to undergo biventricular repair.

Objectives: To determine the long-term outcomes and risk factors for, reintervention after balloon dilation of congenital aortic stenosis in children aged 6 months or older., Background: Although balloon dilation of congenital aortic stenosis has become a primary therapeutic strategy, few data are available regarding long-term outcomes., Methods: We carried out a retrospective review of 87 children who had undergone balloon dilation of the aortic valve at median age of 6.9 years., Results: The procedure was completed in 98% of the children, with an average reduction in the gradient across the valve of 64 +/- 28%, and without mortality. Of the children, 76 had been followed for a mean of 6.3 +/- 4.2 years. Reintervention on the aortic valve was required in 32 children, with 12 undergoing reintervention within 6 months, with 1 death. Another patient had died over the period of follow-up due to a non-cardiac event. Estimated freedom from reintervention was 86% at 1 year, 67% at 5 years, and 46% at 12 years. Parametric modeling of the hazard function showed a brief early phase of increased risk, superimposed on an ongoing constant risk. The only incremental risk factor for the early phase was a residual gradient immediately subsequent to the procedure greater than 30 mmHg. Incremental risk factors for the constant phase included the presence of symmetric valvar opening, and greater than moderate regurgitation immediately after dilation., Conclusion: Long-term survival was excellent, albeit that the need for further reintervention was high due to the palliative nature of the procedure.

Knowledge of normal aortic dimensions is important in the management of children with aortic disease. So as to define such dimensions, we undertook a retrospective review of clinical data and aortic cineangiograms from 167 subjects without aortic disease having a mean age of 3.67 years, with a range from 0.01 to 14.95 years. Amongst the patients, 56 were without detectable cardiac lesions, 66 patients had mild pulmonary stenosis, 30 were seen with Kawasaki disease, and 15 with small interatrial defects within the oval fossa. Aortograms were available in all. No patient had any hemodynamic derangement that would have affected the aorta during intrauterine life or childhood. Systolic dimensions were measured in the ascending and descending aorta at the level of the carina, at the transverse aortic arch distal to the brachiocephalic, of the left common carotid artery at its origin, at the transverse aortic arch distal to the left common carotid artery, at the aortic isthmus, and of the aorta at the level of the diaphragm. A regression analysis model was used to establish the range of predicted normal values, with their confidence limits, standardizing the values to height as the biophysical parameter having the highest correlation to aortic dimensions. Normal ranges were established for all the levels of measurement. The data should prove useful in identifying abnormalities of the thoracic aorta during childhood, and when assessing the outcomes of interventions.

Bilateral arterial ducts represent an uncommon form of pulmonary or systemic blood supply associated with complex congenital cardiac disease. We sought to determine the role of high-resolution cross-sectional echocardiography and color flow Doppler ultrasonography in assessing this condition, as well as to describe the management and outcome in a group of patients. A retrospective review was conducted of 11 newborns identified over a 16-year period as having bilateral arterial ducts. Pulmonary atresia associated with non-confluent pulmonary arteries was the dominant lesion, with the heterotaxy syndrome also frequently being recognized. Echocardiography best identified the source of blood supply to either the pulmonary or systemic circulations, allowing differentiation from collateral vessels. Stenosis of the right or left pulmonary artery at the initial site of ductal insertion needs careful evaluation on follow-up. Management of patients with this condition remains a challenge, as indicated by the poor outcomes observed in our series.

A left superior caval vein frequently occurs in the malformed, as well as in the structurally normal, heart. Its physiological impact varies, and is determined by its connections and whether there are associated cardiac lesions. In this review, we describe 3 patients with such a vein, 1 without other lesions and 2 with the anomalous venous channel as a component of a complex cardiac malformation. In all cases, transcatheter techniques were used to treat the physiological dysfunction caused by the presence of the vein. The connections of the vein, and the complexity of the associated cardiac lesions, determine the options for treatment. We define the role of surgical as opposed to transcatheter intervention, and discuss strategies for transcatheter treatment.

Major abnormalities of pulmonary circulation are uncommon in the patient with pulmonary atresia and intact ventricular septum. Non-confluent pulmonary arteries have only rarely been described in this setting. In this case report, we describe a patient in whom the pulmonary arteries are non-confluent, with the right pulmonary artery supplied through a right-sided arterial duct, and the left pulmonary artery most likely through a fifth aortic arch, thus providing a systemic-to-pulmonary arterial connection. We discuss the various forms of non-confluent pulmonary arteries in the setting of pulmonary atresia and intact ventricular septum.

Objective: To determine factors associated with outcomes after listing for transplantation in children with cardiomyopathies., Background: Childhood cardiomyopathies form a heterogeneous group of diseases, and in many, the prognosis is poor, irrespective of the etiology. When profound heart failure develops, cardiac transplantation can be the only viable option for survival., Methods: We included all children with cardiomyopathy listed for transplantation between 12/89 and 4/98 in this historical cohort study., Results: We listed 31 patients, 15 male and 16 female, 27 with dilated and 4 with restrictive cardiomyopathy, for transplantation. The median age at listing was 5.7 years, with a range from fetal life to 17.8 years. Transplantation was achieved in 23 (74%), with a median interval from listing of 54 days, and a range from zero to 11.4 years. Of the patients, 14 were transplanted within 30 days of listing. Five patients (16%) died before transplantation. Within the Canadian algorithm, one of these was in the third state, and four in the fourth state. One patient was removed from the list after 12 days, having recovered from myocarditis, and two remain waiting transplantation after intervals of 121 and 476 days, respectively. Patients who died were more likely to be female (5/5 vs. 11/26; p=0.04) and to have been in the third or fourth states at listing (5/5 vs. 15/26; p=0.04). The use of mechanical ventricular assistance, in 10 patients, was not a predictor of an adverse outcome. While not statistically significant, survival to transplantation was associated with treatment using inhibitors of angiotensin converting enzyme, less mitral regurgitation, a higher mean ejection fraction and cardiac index, and lower right ventricular systolic pressure., Conclusions: Children with cardiomyopathy awaiting transplantation have a mortality of 16% related to their clinical state at the time of listing.

Doppler derived systolic pressure gradients have become widely applied as noninvasively obtained estimates of the severity of aortic valvar stenosis. There is little correlation, however, between the Doppler derived peak instantaneous gradient and the peak-to-peak gradient obtained at catheterisation, the latter being the most applied variable to determine severity in children. The purpose of this study was to validate a mathematical model based on data from catheterisation which estimates the peak-to-peak gradient from variables which can be obtained by noninvasive means (Doppler derived mean gradient and pulse pressure), according to the formula: peak-to-peak systolic gradient = 6.02+/-1.49*(mean gradient)-0.44*(pulse pressure). Simultaneous cardiac catheterization and Doppler studies were performed on 10 patients with congenital aortic valvar stenosis. Correlations between the gradients measured at catheter measured, and those derived by Doppler, were performed using linear regression analysis. The mean gradients correlated well (y = 0.67 x +11.11, r = 0.87, SEE = 6 mm Hg, p = 0.001). The gradients predicted by the formula also correlated well with the peak-to-peak gradients measured at catheter (y = 0.66 x +14.44, r = 0.84, SEE = 9 mm Hg, p = 0.002). The data support the application of the model, allowing noninvasive prediction of the peak-to-peak gradient across the aortic valvar stenosis.

A patient with pulmonary atresia and intact ventricular septum was found to have a right ventricular-dependent coronary circulation. In this infant both coronary arteries lacked their normal proximal connection with the aorta, perhaps the most egregious form of this prejudicial coronary circulation. Even more interesting was a direct collateral vessel originating from the descending thoracic aorta and connecting with the coronary circulation. This patient has undergone bilateral modified Blalock-Taussig shunts, and left ventricular function seems preserved.

We describe the importance of angiographic identification of collateral venous channels by balloon occlusion venography after bidirectional cavopulmonary connections. Use of the balloon occlusion technique is essential for identification of these vessels, as they can easily be missed by standard venous angiography, with possible clinical consequences for postoperative management.

Dick Rowe (Fig.) would be embarrassed by this attention, as he was such a very modest man. Yet it is appropriate that the late Richard Desmond Rowe be included in Cardiology in the Young's Paediatric Cardiology Hall of Fame. As I consider the life and contributions of Dick Rowe, I am at first troubled, indeed saddened, by the realization that more than a decade has passed since his untimely and premature death just weeks before his planned retirement. I have his picture on the mantle of my office. Not a day goes by that I don't look at his countenance, however fleeting, reflecting on my good fortune to have worked with and considered Dick Rowe as mentor, colleague, teacher and friend. This sense of good fortune is shared by virtually all those touched by his warmth and generosity.

Aortopulmonary septal defect and tetralogy of Fallot is a rare combination. We report a case of tetralogy of Fallot, non-confluent pulmonary arteries with the left arising from the arterial duct, and a large aortopulmonary septal defect diagnosed by echocardiogram and confirmed by cardiac catheterization.

Unlabelled: Anomalous origin of one pulmonary artery from the ascending aorta is an uncommon lesion with an uncertain outcome. We reviewed 16 consecutive children (9 males) presenting with this lesion over a 36 year period at a single institution. Median age at presentation was 2 days (range, birth to 3.2 years). The anomalous pulmonary was the right in 12 and the left in 4, all originating from the proximal ascending aorta, with no patient having stenosis at the origin of the anomalous pulmonary artery. Associated cardiac anomalies were noted in 9 patients. No intervention was attempted in 2 patients: one was deemed inoperable due to complex associated lesions and pulmonary vascular obstructive disease, while the other one died before repair. Surgical intervention was attempted in 14 patients, with 3 intraoperative deaths (21%). Of 11 operative survivors, 8 developed pulmonary arterial stenosis graded severe in 2, moderate in 1 and mild in 5. Patients with severe stenosis required surgical angioplasty, 1 after unsuccessful dilation combined with placement of an endovascular stent. One patient with moderate, and one with mild, stenosis underwent successful transcatheter balloon dilation. The remaining 4 patients with mild stenosis remain unchanged during follow-up. One patient had biopsy evidence of pulmonary vascular obstructive disease at 3.3 years of age. There were no late deaths, giving a total mortality of 25% (4/16)., Conclusion: While early diagnosis and repair of anomalous origin of one pulmonary artery from the ascending aorta is necessary, restenosis of the site of repair is common.