Redefining Expectations of Long-Term Survival After the Fontan Procedure

The Role of Echocardiography and Intracardiac Exploration in the Evaluation of Candidacy for Biventricular Repair in Patients With Borderline Left Heart Structures

BACKGROUND

Predictors for single ventricle palliation (SVP) or successful biventricular repair (BVR) in patients with borderline left-side heart structures are not well defined. The goal was to evaluate the role of echocardiography and intracardiac exploration in determining feasibility of BVR.

METHODS

All neonates surgically treated from 1995 to 2015 with mitral valve (MV), aortic valve, or left ventricle end-diastolic dimension z score of -2 or less for whom management was controversial were included. Data were analyzed using Fisher's exact test, Kruskal-Wallis test, and Kaplan-Meier analysis.

RESULTS

The cohort consisted of 42 patients: 7 SVP (17%) and 35 BVR (83%). Median follow-up was 7 years (range, 6 months to 18 years). Intracardiac exploration was performed in 29 patients (69%). There was poor correlation between echocardiographic and intraoperative MV measurements (intraclass correlation coefficient 0.14). Preoperative echocardiography significantly underestimated MV size in 14 patients (54%). Two BVR patients were converted to SVP, and 4 (including 1 converted patient) had cardiac-related deaths. All patients with MV greater than 8 mm on preoperative echocardiography had successful BVR. An intraoperative MV less than 8 mm and an abnormal subvalvar apparatus was present in 5 of 6 SVP (83%) and 3 of 3 (100%) failed BVR patients who had intracardiac exploration, and in only 1 of 20 successful BVR patients (5%) who had an intracardiac exploration.

CONCLUSIONS

The decision to proceed to BVR in patients with borderline left-side heart structures should not rely strictly on echocardiographic measurements. Intracardiac exploration of the MV and subvalvar apparatus is useful before committing a patient to SVP. Patients with low MV z scores, especially those with a normal subvalvar apparatus, may undergo BVR with good outcomes.

Thromboembolism and anticoagulation after Fontan surgery

This review attempts to answer the common questions faced by a clinician regarding thromboembolism and thromboprophylaxis in patients following Fontan surgery. The review is in an easy to understand question and answer format and discusses the currently available literature on the subject in an attempt to arrive at practical clinically relevant solutions. Patients who have undergone the Fontan operation are at a high risk for thromboembolism. Based on available evidence, there is a strong rationale for thromboprophylaxis. However, it is not clear as to which agent should be administered to prevent thromboembolic events. While the available evidence suggests that antiplatelet agents alone may be as good as oral anticoagulants, there is a need for a large multicenter randomized control trial comparing these two common strategies to deliver a clear verdict.

Long-term outcomes after first-onset arrhythmia in Fontan physiology

OBJECTIVES

Patients living with a Fontan circulation are prone to develop arrhythmias. However, their prognostic impact has been seldom studied. As such, we aimed to determine the incidence and predictors of arrhythmias after the Fontan procedure and the long-term outcomes after the first onset of arrhythmias.

METHODS

Of the 1034 patients who have undergone a Fontan procedure as recorded in the Australian and New Zealand Fontan Registry, we identified those in whom a tachyarrhythmia or bradyarrhythmia developed. We evaluated the incidence and predictors of developing arrhythmias and their prognostic impact on late outcomes.

RESULTS

Arrhythmia developed in 195 patients. Tachyarrhythmia was present in 162 patients, bradyarrhythmia was present in 74 patients, and both forms were present in 41 patients. At 20 years, freedom from any arrhythmia, tachyarrhythmia, and bradyarrhythmia was 66% (95% confidence interval [CI], 59-72), 69% (95% CI, 62-75), and 85% (95% CI, 80-90), respectively. On multivariable analyses, patients with an extracardiac Fontan (hazard ratio [HR], 0.23; 95% CI, 0.10-0.51; P < .001) were less likely to develop an arrhythmia, whereas those with left atrial (HR, 3.18; 95% CI, 1.45-6.95; P = .004) and right atrial (HR, 4.00; 95% CI, 2.41-6.61; P < .001) isomerism were more likely to have an arrhythmia. After onset of any arrhythmia (tachyarrhythmia or bradyarrhythmia), 10- and 15-year survivals were 74% (65%-83%) and 70% (60%-80%), respectively, and freedom from Fontan failure was 55% (44%-64%) and 44% (32%-56%), respectively. The development of any arrhythmia (HR, 2.20; 95% CI, 1-44-3.34; P < .001), tachyarrhythmia (HR, 2.56; 95% CI, 1.60-4.11; P < .001), and bradyarrhythmia (HR, 1.85; 95% CI, 1.16-2.95; P = .01) were all independent predictors of late Fontan failure on multivariable analyses.

CONCLUSIONS

The development of an arrhythmia is associated with a heightened risk of subsequent failure of the Fontan circulation.

Regenerative Medicine Strategies for Hypoplastic Left Heart Syndrome

Hypoplastic left heart syndrome (HLHS), the most severe and common form of single ventricle congenital heart lesions, is characterized by hypoplasia of the mitral valve, left ventricle (LV), and all LV outflow structures. While advances in surgical technique and medical management have allowed survival into adulthood, HLHS patients have severe morbidities, decreased quality of life, and a shortened lifespan. The single right ventricle (RV) is especially prone to early failure because of its vulnerability to chronic pressure overload, a mode of failure distinct from ischemic cardiomyopathy encountered in acquired heart disease. As these patients enter early adulthood, an emerging epidemic of RV failure has become evident. Regenerative medicine strategies may help preserve or boost RV function in children and adults with HLHS by promoting angiogenesis and mitigating oxidative stress. Rescuing a RV in decompensated failure may also require the creation of new, functional myocardium. Although considerable hurdles remain before their clinical translation, stem cell therapy and cardiac tissue engineering possess revolutionary potential in the treatment of pediatric and adult patients with HLHS who currently have very limited long-term treatment options.

Management of supraventricular arrhythmias in adults with congenital heart disease

Supraventricular arrhythmias are a frequent complication in adults with congenital heart disease (ACHD). The prevalence increases with time since surgery, complexity of the underlying defect, type of repair and older age at surgery. Arrhythmias are the most frequent reason for hospital admission and along with heart failure the leading cause of death. The arrhythmia-associated increase in morbidity and mortality makes their management a key task in patients with ACHD. Intra-atrial re-entry is the most frequent arrhythmia mechanism. Less common arrhythmia mechanisms are supraventricular tachycardias in the presence of an accessory pathway, atrioventricular nodal re-entrant tachycardia or focal tachycardias. Patient management includes stroke prevention, acute termination and prevention of arrhythmia recurrence. Acute treatment depends on patients' symptoms. In cases of haemodynamic instability, immediate cardioversion is warranted. For stable patients, acute treatment includes rate control and termination by antiarrhythmic drugs or electrical cardioversion. Following a symptomatic arrhythmia, catheter ablation or treatment with antiarrhythmic drugs is recommended to prevent recurrences. Advances in mapping and ablation technology are now associated with high success rates of catheter ablation. In patients with a complex substrate recurrence rates of 50% remain high. However, in the presence of side effects and complications associated with long-term antiarrhythmic drug therapy, redo procedures are encouraged by current guidelines.

[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.

Drug therapy in the prevention of failure of the Fontan circulation: a systematic review

BACKGROUND

The Fontan circulation is the optimal treatment for patients with univentricular hearts. These patients are at high risk of circulatory failure. There is no consensus on the optimal drug treatment for the prevention of failure of the Fontan circulation. The aim of this systematic review was to provide an overview of evidence for drug therapy used in the prevention of Fontan circulatory failure.

METHODS

We searched the Embase database for articles that reported drug therapy in Fontan patients. Studies published between 1997 and 2014 were included if efficacy or safety of medication was assessed, drug therapy aimed to prevent or treat failure of the Fontan circulation, and if the full text was available. Case reports were excluded.

RESULTS

A total of nine studies were included with a total of 267 Fontan patients; four studies evaluated the medication sildenafil, one iloprost, three bosentan, and one enalapril. Among all, two sildenafil studies reported improvement in exercise capacity, one in exercise haemodynamics, and one in ventricular performance. In the largest study of bosentan, an increase in exercise capacity was found. Enalapril did not result in improvements.

CONCLUSION

The studies analysed in this review suggest that bosentan, sildenafil, and iloprost may improve exercise capacity at the short term. Given the limitations of the studies, more, larger, placebo-controlled studies with longer follow-up periods are needed to better understand which drug therapies are effective in the prevention of failure of the Fontan circulation.

Improved survival after heart transplant for failed Fontan patients with preserved ventricular function

BACKGROUND

Patients with a failing Fontan continue to have decreased survival after heart transplant (HT), particularly those with preserved ventricular function (PVF) compared with impaired ventricular function (IVF). In this study we evaluated the effect of institutional changes on post-HT outcomes.

METHODS

Data were retrospectively collected for all Fontan patients who underwent HT. Mode of failure was defined by the last echocardiogram before HT, with mild or no dysfunction considered PVF and moderate or severe considered IVF. Outcomes were compared between early era (EE, 1995 to 2008) and current era (CE, 2009 to 2014). Management changes in the CE included volume load reduction with aortopulmonary collateral (APC) embolization, advanced cardiothoracic imaging, higher goal donor/recipient weight ratio and aggressive monitoring for post-HT vasoplegia.

RESULTS

A total of 47 patients were included: 27 in the EE (13 PVF, 14 IVF) and 20 in the CE (12 PVF, 8 IVF). Groups were similar pre-HT, except for more PLE in PVF patients. More patients underwent APC embolization in the CE (80% vs 28%, p < 0.01). There was no difference in donor/recipient weight ratio between eras. There was a trend toward higher primary graft failure for PVF in the EE (77% vs 36%, p = 0.05) but not the CE (42% vs 75%, p = 0.20). Overall, 1-year survival improved in the CE (90%) from the EE (63%) (p = 0.05), mainly due to increased survival for PVF (82 vs 38%, p = 0.04).

CONCLUSIONS

Post-HT survival for failing Fontan patients has improved, particularly for PVF. In the CE, our Fontan patients had a 1-year post-HT survival similar to other indications.

Fontan Conversion

Early survival after the Fontan operation has improved significantly leading to a lifetime of Fontan circulation for patients. There is a natural progression of pulmonary artery pressure during the human lifetime that is easily tolerated in two-ventricle physiology but is deleterious for single-ventricle physiology. Obstructions in the venous to pulmonary artery pathway and pulmonary venous return or ventricular outflow, atrioventricular valve dysfunction (regurgitation), pulmonary arteriovenous malformations, venous thrombosis, and the development of atrial arrhythmias can lead to reduced functional status. These complications have been demonstrated in older patients with largely atriopulmonary connections owing to time accrual and unfavorable flow characteristics. Various surgical and catheter interventions aimed at reducing morbidity and mortality have been attempted to treat these identifiable abnormalities. The purpose of this article is to review the extant literature on Fontan Conversion and to assess the lessons learned over 20 years.

Concepts from paediatric extracorporeal membrane oxygenation for adult intensivists

Over the last 5 years, there has been a dramatic increase in the use of extracorporeal membrane oxygenation (ECMO) in adult patients with severe respiratory or cardiac failure. This contrasts to the use of the technology in neonatal and paediatric intensive care units, where it has been regarded as a standard of care for a number of conditions for over 25 years. Many innovations in ECMO circuitry or clinical management evolve first in one particular discipline and it may be helpful for individual clinicians to keep abreast of developments in ECMO across the entire age range, from neonatology to older adults. This review addresses nine concepts in ECMO that are better studied or established in paediatric medicine and considers their application in adult patients.

Use of ACE inhibitors in Fontan: Rational or irrational?

BACKGROUND

Despite a lack of evidence supporting the use of angiotensin-converting enzyme (ACE) inhibitors in patients with a Fontan circulation, their use is frequent. We decided to identify the rationale for ACE inhibitor therapy in patients within the Australia and New Zealand Fontan Registry.

METHODS

All patients in the Registry taking an ACE inhibitor at last follow up were identified, and a review of medical records was undertaken to determine the rationale for treatment initiation and reasons for treatment continuation or dose increase.

RESULTS

In 2015, 36% of the surviving patients in the Registry (462/1268) were taking an ACE inhibitor. Indications for initiation of therapy were ventricular systolic or diastolic dysfunction (29%), atrioventricular valve regurgitation (19%), preservation of normal ventricular function (7%), prolonged effusions at Fontan (6%), hypertension (6%), other (6%) and unknown (2%). No indication was stated in the remaining patients (25%). Those with hypoplastic left heart syndrome were more likely to be on an ACE inhibitor than those with an alternative primary morphology (70% vs 32%; p<0.001). Only 36% of the patients treated with an ACE inhibitor at last follow up (166/462) had an indication that would generally justify treatment in a two-ventricle circulation.

CONCLUSION

It is likely that the use of ACE inhibitors in patients with a Fontan circulation is excessive within our region. The coordination of prospective, multicentre studies and initiatives such as the Australia and New Zealand Fontan Registry will facilitate further investigations to guide treatment decisions in the growing Fontan population.

Liver Disease in Patients After the Fontan Operation

We reviewed records of all patients with an initial Fontan operation or revision from 1973 to 2012 at our institution (n = 1,138); 195 patients had postoperative liver data available. Cirrhosis was identified by histopathology or characteristic findings on imaging with an associated diagnosis of cirrhosis by a hepatologist. Of 195 patients with biopsy or imaging, 10-, 20-, and 30-year freedom from cirrhosis was 99%, 94%, and 57%, respectively. There were 40 of 195 patients (21%) diagnosed with cirrhosis (mean age at Fontan 10.7 ± 8 years). On multivariate analysis, hypoplastic left heart syndrome was associated with increased risk of cirrhosis (n = 2 of 16, p = 0.0133), whereas preoperative sinus rhythm was protective (p = 0.009). Survival after diagnosis of cirrhosis was 57% and 35%, at 1, and 5 years, respectively. The cause of death was known for 9 patients (5 multiorgan failure, 2 liver failure, and 2 heart failure). In conclusion, there is an incremental occurrence of cirrhosis after the Fontan, which should be considered when designing follow-up protocols for patients after Fontan operation.

The Relentless Effects of the Fontan Paradox

The Fontan operation is the anticipated palliative strategy for children born with single-ventricle type of congenital heart disease. As a result of important circulatory limitations, a series of end-organ complications are now increasingly recognized. Elevated central venous pressure and impaired cardiac output are the hallmarks of cavo-pulmonary flow, which result in a cascade of pathophysiological consequences. The Fontan circulation likely impacts all organ systems in an indolent and relentless manner, with progressive decline in functionality likely to occur in many. Liver fibrosis, altered bone density, decreased muscle mass, renal dysfunction, lymphatic insufficiency, and a host of other conditions are present. Standardized screening and evaluation of survivors as they grow through childhood and beyond is indicated and can be facilitated through dedicated multidisciplinary clinical programs. Invasive assessment at specific milestones can provide important actionable information to optimize individual status. More detailed characterization and understanding of these end-organ complications is necessary to contribute to the goal of achieving a normal duration and quality of life for these unique individuals.

Is Four Stage Management the Future of Univentricular Hearts? Destination Therapy in the Young

For the child born with a functionally univentricular heart, multi-stage surgical palliation culminating in the Fontan operation is now well established as the standard of care. Though this is an effective approach, there are several inherent disadvantages to the Fontan circulation: subnormal resting cardiac output, impaired exercise capacity, increased risk of thromboembolism, and increased risk of arrhythmia. Perhaps most importantly, the long-term deleterious effects of substantial systemic venous hypertension, which is necessary to "drive" blood through the pulmonary vascular bed, include progressive dysfunction of other organ systems, particularly renal, lymphatic, gastrointestinal, and hepatic systems. When such dysfunction is advanced, heart transplantation or even heart-liver transplantation may be a reasonable option. However, because the syndrome seems to be increasingly widespread and there is already a significant donor shortage, alternative solutions are required. Because many patients with "failing Fontan" physiology have preserved systemic ventricular function, application of a systemic ventricular assist device is unlikely to be effective. However, for such patients, a right-sided sub-pulmonary ventricular assist device is an intellectually appealing solution. Several such devices have been proposed or are in varying stages of evaluation. The lack of economic incentive for development of right-sided pumps may be partially ameliorated both by recognition of the size of the cohort of Fontan patients now surviving into adulthood as well as by the increasing recognition of important right-sided heart failure in adults with biventricular hearts supported only with durable left-sided ventricular assist devices.

Pulmonary Artery Reconstruction with Donor Aortic Homograft During Cardiac Transplantation in the Failed Fontan Circulation

The advanced surgical management of patients with single ventricle physiology, in particular the hypoplastic left heart syndrome, has resulted in an increased number of patients with a Fontan circulation. In a proportion of these patients, the Fontan circulation will ultimately fail and cardiac transplantation may be required. Their course may be complicated by the hemodynamic consequences of the failing Fontan, multiple previous operations, and the frequent need for complex reconstruction at transplantation. We describe a patient with a failed modified Fontan circulation requiring concomitant pulmonary artery reconstruction and cardiac transplantation and review potential reconstruction techniques.

Mortality-related resource utilization in the inpatient care of hypoplastic left heart syndrome

BACKGROUND

Quantifying resource utilization in the inpatient care of congenital heart diease is clinically relevant. Our purpose is to measure the investment of inpatient care resources to achieve survival in hypoplastic left heart syndrome (HLHS), and to determine how much of that investment occurs in hospitalizations that have a fatal outcome, the mortality-related resource utilization fraction (MRRUF).

METHODS

A collaborative administrative database, the Pediatric Health Information System (PHIS) containing data for 43 children's hospitals, was queried by primary diagnosis for HLHS admissions of patients ≤21 years old during 2004-2013. Institution, patient age, inpatient deaths, billed charges (BC) and length of stay (LOS) were recorded.

RESULTS

In all, 11,122 HLHS admissions were identified which account for total LOS of 277,027 inpatient-days and $3,928,794,660 in BC. There were 1145 inpatient deaths (10.3%). LOS was greater among inpatient deaths than among patients discharged alive (median 17 vs. 12, p < 0.0001). BC were greater among inpatient deaths than among patients discharged alive (median 4.09 × 10(5) vs. 1.63 × 10(5), p < 0.0001). 16% of all LOS and 21% of all BC were accrued by patients who did not survive their hospitalization. These proportions showed no significant change year-by-year. The highest volume institutions had lower mortality rates, but there was no relation between institutional volume and the MRRUF.

CONCLUSIONS

These data should alert providers and consumers that current practices often result in major resource expenditure for inpatient care of HLHS that does not result in survival to hospital dismissal. They highlight the need for data-driven critical review of standard practices to identify patterns of care associated with success, and to modify approaches objectively.

The Fontan operation: the long-term outlook

PURPOSE OF REVIEW

As perioperative survival following the Fontan procedure has improved and more patients are reaping the benefits of physiologic palliation, the costs of longstanding systemic venous hypertension and the functional limitations of a single ventricle are becoming clearer. Arrhythmias, heart failure, protein-losing enteropathy, hepatic cirrhosis, pulmonary hypertension, and ventricular dysfunction are common in late survivors and result in significant morbidity and mortality. Current research is focused on characterizing late morbidities and developing risk-prediction models for worse outcomes in long-term survivors.

RECENT FINDINGS

Ten-year survival following the Fontan procedure is now 94-98%; however, estimated conditional survival in survivors aged above 18 years is 60% at 40 years of age. Atrial arrhythmias and heart failure are the leading causes of morbidity and mortality. Hypoplastic left heart syndrome, hepatic dysfunction, decreased exercise tolerance, lower quality of life, and markers of neurohormonal activation have been associated with worse outcome. Improvements in exercise tolerance are seen with selective pulmonary vasodilator therapy and exercise training. Heart transplant continues to be an effective therapy for end-stage Fontan failure, and reports of the use of traditional mechanical assist devices and the development of right heart assist devices in the setting of passive venous flow are ongoing.

SUMMARY

Over a generation has passed since the Fontan procedure revolutionized the care of patients with a single ventricle. Data generated from retrospective and prospective observational studies in long-term survivors are identifying patients at risk.

Unsatisfactory Early and Late Outcomes After Fontan Surgery Delayed to Adolescence and Adulthood

The ideal age to perform the Fontan procedure is still unknown. The aim of this study is to determine outcomes after Fontan surgery delayed to adolescence and adulthood in Australia and New Zealand. Patients who had undergone a Fontan procedure at 15 years of age or older were identified in the 1133 patients registered in the Australia and New Zealand Fontan Registry until December 2012. A total of 45 patients underwent the following Fontan procedure at a median age of 18.3 years (16-21 years): 24 atriopulmonary connections, 10 lateral tunnel, and 11 extracardiac conduits. Hospital mortality was 13% (6 of 45). After a mean follow-up of 15.5 ± 9 years, there were 8 late deaths. Survival rates after 10, 20, and 25 years were 79% (95% CI: 64-89), 70% (95% CI: 51-83), and 70% (95% CI: 51-83), respectively. Freedom from Fontan failure (death, heart transplantation, Fontan takedown, protein-losing enteropathy, and poor functional status) after 10 and 20 years was 63% (95% CI: 47-76) and 35% (95% CI: 19-52), respectively. Patients with a single left ventricle had a lower risk of failure (hazard ratio = 0.25, 95% CI: 0.10-0.59; P = 0.002). Arrhythmias developed in 29 patients after a median of 0.1 years (0-9.3 years) and 10 required a permanent pacemaker. Freedom from all adverse events at 10 years was 30% (95% CI: 16-45). Outcomes of the Fontan procedure in adolescents and adults are poor, with disproportionately high hospital mortality and late adverse events. The Fontan procedure should not be delayed to adolescence and adulthood and should be performed electively in childhood.

Learning and evolving

It is an honour to present the Anthony Chang lecture at this 10th International Conference of the Pediatric Cardiac Intensive Care Society. I have had the privilege of knowing Dr Chang for over 20 years, and although we only worked for a short period of time together at the Children's Hospital, Boston, in the Cardiac Intensive Care Unit, we have remained close colleagues and friends since that time. The contributions of Dr Chang to the development of paediatric cardiac intensive care are very clear, based on his clinical expertise, research and scholarship, and the development of the Pediatric Cardiac Intensive Care Society in its early days. More than this, Dr Chang is an individual with vision; in many respects, he has been ahead of the curve, anticipating and leading the direction of paediatric cardiac intensive care.

Bioengineering and Stem Cell Technology in the Treatment of Congenital Heart Disease

Congenital heart disease places a significant burden on the individual, family and community despite significant advances in our understanding of aetiology and treatment. Early research in ischaemic heart disease has paved the way for stem cell technology and bioengineering, which promises to improve both structural and functional aspects of disease. Stem cell therapy has demonstrated significant improvements in cardiac function in adults with ischaemic heart disease. This finding, together with promising case studies in the paediatric setting, demonstrates the potential for this treatment in congenital heart disease. Furthermore, induced pluripotent stems cell technology, provides a unique opportunity to address aetiological, as well as therapeutic, aspects of disease.

Bone density in children with single ventricle physiology

Children with chronic diseases are at risk for low bone mineral density (BMD). There are no studies of BMD in children with congenital heart disease and particularly single ventricle (SV). Children with this defect are often treated with warfarin, suspected to negatively impact BMD in adults. We assessed BMD in patients with SV physiology and compared the BMD of subjects taking warfarin to those who were not. Subjects 5-12 years with SV were included. BMD z scores by dual-energy X-ray absorptiometry of the spine and total body less head (TBLH) were obtained. Calcium intake, activity level, height, and Tanner stage were assessed. Linear regression models and t tests were used to investigate differences between participants and normative data as well as between subjects' subgroups. Twenty-six subjects were included and 16 took warfarin. Mean BMD z score at the spine was significantly lower than expected at -1.0 ± 0.2 (p < 0.0001), as was the BMD z score for TBLH at -0.8 ± 0.2 (p < 0.0001). Those results remained significant after adjusting for height. Subjects who were on warfarin tended to have lower BMD at both the spine and TBLH than those who were not, with a z score difference of 0.6 ± 0.46 at the spine (p = 0.106) and a difference of 0.4 ± 0.34 at TBLH (p = 0.132). BMD is significantly reduced in children with SV. Warfarin appears to lower BMD but the effect is less conclusive. Continued evaluation is recommended for these patients at risk for reduced bone density. Evaluation of other cardiac patients on warfarin therapy should also be considered.

Transplantation in the Fontan patient

The failing Fontan circulation presents difficult treatment challenges. When Fontan revision and or intervention for treatable arrhythmias is not feasible, heart transplantation is the only therapeutic option. Particular challenges presented by these patients include limited ability to assess hemodynamics, complex anatomy, multiple prior procedures, and unique underlying pathologic states. These issues complicate the decision-making process for further surgical intervention verses transplantation. The pre-transplant evaluation, transplant operation, and post-operative management are more problematic for these patients compared with most patients undergoing transplantation. Consequently, failing Fontan patients constitute one of the highest risk heart transplant subsets.

"Functionally" univentricular hearts: impact of pre-natal diagnosis

Within the last few decades the pre-natal echocardiographic diagnosis of congenital heart defects has made substantial progresses, particularly for the identification of complex malformation. "Functionally" univentricular hearts categorize a huge variety of heart malformations. Since no one of the patients with these congenital heart defects can ever undergo a bi-ventricular type of repair, early recognition and decision-making from the neonatal period are required in order to allow for appropriate multiple-step diagnostic and treatment procedures, either of interventional cardiology and/or surgery, on the pathway of "univentricular" heart. In the literature strong disagreements exist about the potential impact of the pre-natal diagnosis on the early and late outcomes of complex congenital heart defects. This review of the recent reports has been undertaken to better understand the impact of pre-natal diagnosis in "functionally" univentricular hearts taking into consideration the following topics: pre-natal screening, outcomes and survival, general morbidity, neurologic and developmental consequences, pregnancy management and delivery planning, resources utilization and costs/benefits issues, ethical implications, parents counseling, and interruption of pregnancy versus treatment.

Hypoplastic left heart syndrome - unresolved issues

Hypoplastic left heart syndrome (HLHS) is one of the most challenging congenital heart defects. At present, it is expected that - at best - 70% of newborns with HLHS will reach adulthood. This review addresses the problems of right ventricular (RV) failure and insufficient growth of pulmonary vasculature in these patients. In order to further improve long-term prognosis translational research to control RV function, growth of pulmonary arteries and progress in chronic circulatory support are clearly needed to provide a further improvement for adults with HLHS.