Pulmonary arterial hypertension in adults with congenital heart disease: distinct differences from other causes of pulmonary arterial hypertension and management implications

The Right Heart in Congenital Heart Disease

PURPOSE OF REVIEW

To analyze the pathophysiologic importance of the right heart in different types of congenital heart disease (CHD), summarize current diagnostic modalities, and discuss treatment options.

RECENT FINDINGS

The right ventricle (RV) plays a key role in disease progression and prognosis, either as the subpulmonary or as the systemic ventricle. Volume and/or pressure overload as well as intrinsic myocardial disease are the main factors for RV remodeling. Echocardiography and cardiac magnetic resonance imaging are important noninvasive modalities for assessing anatomy, size, and function of the right heart. Timely repair of related lesions is essential for preventing RV dysfunction. Few inconclusive data exist on conventional pharmacotherapy in CHD-related RV dysfunction. Cardiac resynchronization therapy and ventricular assist devices are an option in patients with advanced systemic RV failure. Right heart disease is highly related with adverse clinical outcomes in CHD. Research should focus on early identification of patients at risk and development of medical and interventional treatments that improve RV function.

Anesthetic Management of a Down Syndrome Patient for Ventricular Septal Defect Repair: A Case Report

It is commonly known that Down syndrome (DS) and congenital cardiovascular abnormalities go hand in hand. Most frequently, complete atrioventricular septal abnormalities have been linked to DS. Along with DS, ventricular septal defect (VSD), atrial septal defect, tetralogy of Fallot, and patent ductus arteriosus have also been reported. We present a case of DS with VSD who underwent VSD correction. Echocardiography prompted the diagnosis, which was then confirmed by surgery. The patient was successfully transferred out of the hospital. After correcting the VSD, the survival and quality of life of the DS patient have improved.

Differential serum lipid distribution in IPAH and CHD-PAH patients

Lipid homeostasis is dysregulated in pulmonary arterial hypertension (PAH). A decrease in serum high- and low-density lipoprotein cholesterol (HDL-C and LDL-C) is significantly associated with the worse prognosis of PAH. However, no study has investigated the differential distribution of lipids in various PAH subtypes. We enrolled 190 patients in this retrospective study, which includes 20 patients with congenital heart disease without PAH (CHD-nonPAH), 101 patients with PAH associated with congenital heart disease (CHD-PAH), 69 patients with idiopathic PAH (IPAH) and 81 healthy controls. Laboratory parameters such as liver and renal function, serum lipids, C-reactive protein, N-terminal pro-brain natriuretic peptide (NT-proBNP), echocardiography, right heart catheterization and 6-min walk distance (6MWD) were performed. All types of cholesterol including HDL-C, LDL-C and total cholesterol (CHOL) were significantly lower in IPAH patients in association with right heart function. Although LDL-C and CHOL were lower in CHD-PAH, they were not associated with disease severity or heart failure. Thus, we conclude that IPAH and CHD-PAH patients exhibited a differential distribution pattern of serum lipids.

Review of evidence for bosentan therapy for treatment of Eisenmenger syndrome

BACKGROUND AND PURPOSE

Eisenmenger syndrome (ES) is a rare condition caused by a right-to-left cyanotic shunt. To date, only heart-lung transplant has been shown to be curative. Bosentan is the only medication studied with a double-blind placebo-controlled randomized trial for management of this condition. The intent of this article is to explore the literature surrounding bosentan in ES and assess its efficacy.

METHODS

A literature review was conducted with no limitation on date. Titles were scanned for applicability, and abstracts of those articles found to be pertinent were reviewed. Those articles considered relevant based on the abstract were read in entirety.

CONCLUSIONS

Eisenmenger syndrome remains incurable except through heart-lung transplant. Although no specific medical treatment or algorithm exists, three pharmacological classes show promise in disease management: endothelin receptor antagonists, phosphodiesterase inhibitors, and prostacyclins. Combined therapy with these agents may improve cardiopulmonary function. Bosentan has not been proven as a monotherapy for ES and is not appropriate in all patients as side effects are commonly reported.

IMPLICATIONS FOR PRACTICE

Further study is required to assess efficacy of combination therapy and utilization as a bridge to transplant or surgical correction of the underlying defect.

Impact of Non-cardiac Comorbidities in Adults with Congenital Heart Disease: Management of Multisystem Complications

The prevalence and impact of non-cardiac comorbidities in adult patients with congenital heart disease increase over time, and these complications are often specifically a consequence of the long-term altered cardiovascular physiology or sequelae of previous therapies. For the ACHD patient admitted to the intensive care unit (ICU) for either surgical or medical treatment, an assessment of the burden of multisystem disease, as well as an understanding of the underlying cardiovascular pathophysiology, is essential for optimal management of these complex patients. This chapter takes an organ-system-based approach to reviewing common comorbidities in the ACHD patient, focusing on conditions that are directly related to ACHD status and may significantly impact ICU care.

How to evaluate patients with congenital heart disease-related pulmonary arterial hypertension

INTRODUCTION

Patients with congenital heart disease (CHD), who develop pulmonary arterial hypertension (PAH), live longer, and have better quality of life compared to the past due to PAH-specific therapy and improved tertiary care. Areas covered: Clinical examination, objective assessment of functional capacity, natriuretic peptide levels, cardiac imaging, and hemodynamics all play a pivotal role in the evaluation, general care, and management of PAH-specific therapy. This review discusses the epidemiology and pathophysiology of PAH-CHD and provides hints for the optimal evaluation of these patients. Expert commentary: Further research should be performed in the field of PAH-CHD, as there are many of areas lacking evidence that should be addressed in the future. Networking, especially among the tertiary expert centers, could play a key role in this direction.

Phosphodiesterase type 5 inhibitors improve microvascular dysfunction markers in pulmonary arterial hypertension associated with congenital heart disease

BACKGROUND

Ideally, vasodilator therapies for pulmonary arterial hypertension (PAH) should have a favorable impact on markers of vascular dysfunction, in addition to their known effects on hemodynamics, cardiac function, and patient's physical capacity.

METHODS

We analyzed circulating (plasma) markers of endothelial and platelet activation/dysfunction (enzyme-linked immunoassays) in the specific setting of advanced PAH associated with congenital heart disease, during the course of sildenafil and tadalafil therapies. Thirty-one patients were enrolled (age 10-54 years), most of them with chronic hypoxemia and elevated hematocrit. Drugs were administered orally for 6 months (sildenafil [n = 16], 20 mg t.i.d.; tadalafil [n = 15], single daily dose of 40 mg). Measurements were performed at baseline, and 90 and 180 days.

RESULTS

Compared to controls, patients had elevated baseline β-thromboglobulin (β-TG, P = .002), P-selectin (P = .027), tissue-type plasminogen activator (t-PA, P = .009), and von Willebrand factor antigen (VWF:Ag, P = .010). Thrombomodulin was importantly reduced (TM, P < .001), while soluble CD40 Ligand was not changed (P = .320). Tadalafil administration was associated with improvement of β-TG (P = .004), t-PA (P = .003) and TM (P = .046) levels, while P-selectin was improved by sildenafil treatment only (P = .034). VWF:Ag improved transiently in the sildenafil group (P = .019). Both therapies were associated with improvement of the physical capacity (functional class and distance walked during the 6-minute test, P < .05), hematocrit and hemoglobin level (P < .05), and health-related quality of life (physical and mental components, P < .05).

CONCLUSION

In PAH associated with congenital heart disease, phosphodiesterase 5 inhibitors seem to have beneficial actions at microcirculatory level, beyond the proposed effects as vasodilators.

Hospitalisations for heart failure predict mortality in pulmonary hypertension related to congenital heart disease

OBJECTIVE

Despite the progress in the management of patients with adult congenital heart disease (ACHD), a significant proportion of patients still develop pulmonary hypertension (PH). We aimed to highlight the rate of the complications in PH-ACHD and the predicting factors of cumulative mortality risk in this population.

METHODS

Data were obtained from the cohort of the national registry of ACHD in Greece from February 2012 until January 2018.

RESULTS

Overall, 65 patients receiving PH-specific therapy were included (mean age 46.1±14.4 years, 64.6% females). Heavily symptomatic (New York Heart Association (NYHA) class III/IV) were 53.8% of patients. The majority received monotherapy, while combination therapy was administered in 41.5% of patients. Cardiac arrhythmia was reported in 30.8%, endocarditis in 1.5%, stroke in 4.6%, pulmonary arterial thrombosis in 6.2%, haemoptysis in 3.1% and hospitalisation due to heart failure (HF) in 23.1%. Over a median follow-up of 3 years (range 1-6), 12 (18.5%) patients died. On univariate Cox regression analysis history of HF hospitalisation emerged as a strong predictor of mortality (HR 8.91, 95% CI 2.64 to 30.02, p<0.001), which remained significant after adjustment for age and for NYHA functional class.

CONCLUSIONS

Long-term complications are common among patients with PH-ACHD. Hospitalisations for HF predict mortality and should be considered in the risk stratification of this population.

Pulmonary Arterial Hypertension: Iron Matters

The interplay between iron and oxygen is longstanding and central to all aerobic life. Tight regulation of these interactions including homeostatic regulation of iron utilization ensures safe usage of this limited resource. However, when control is lost adverse events can ensue, which are known to contribute to an array of disease processes. Recently, associations between disrupted iron homeostasis and pulmonary artery hypertension (PAH) have been described with the suggestion that there is a contributory link with disease. This review provides a background for iron regulation in humans, describes PAH classifications, and discusses emerging literature, which suggests a role for disrupted iron homeostatic control in various sub-types of PAH, including a role for decompartmentalization of hemoglobin. Finally, the potential for therapeutic options to restore iron homeostatic balance in PAH are discussed.

Arrhythmias in adult patients with congenital heart disease and pulmonary arterial hypertension

OBJECTIVES

Approximately 5%-10% of adults with congenital heart disease (CHD) develop pulmonary arterial hypertension (PAH), which affects life expectancy and quality of life. Arrhythmias are common among these patients, but their incidence and impact on outcome remains uncertain.

METHODS

All adult patients with PAH associated with CHD (PAH-CHD) seen in a tertiary centre between 2007 and 2015 were followed for new-onset atrial or ventricular arrhythmia. Clinical variables associated with arrhythmia and their relation to mortality were assessed using Cox analysis.

RESULTS

A total of 310 patients (mean age 34.9±12.3 years, 36.8% male) were enrolled. The majority had Eisenmenger syndrome (58.4%), 15.2% had a prior defect repair and a third had Down syndrome. At baseline, 14.2% had a prior history of arrhythmia, mostly supraventricular arrhythmia (86.4%). During a median follow-up of 6.1 years, 64 patients developed at least one new arrhythmic episode (incidence 3.47% per year), mostly supraventricular tachycardia or atrial fibrillation (78.1% of patients). Arrhythmia was associated with symptoms in 75.0% of cases. The type of PAH-CHD, markers of disease severity and prior arrhythmia were associated with arrhythmia during follow-up. Arrhythmia was a strong predictor of death, even after adjusting for demographic and clinical variables (HR 3.41, 95% CI 2.10 to 5.53, p<0.0001).

CONCLUSIONS

Arrhythmia is common in PAH-CHD and is associated with an adverse long-term outcome, even when managed in a specialist centre.

The Effect of Endothelin Receptor Antagonists in Patients with Eisenmenger Syndrome: A Systematic Review

INTRODUCTION

The efficacy of endothelin receptor antagonists (ERAs) in the management of Eisenmenger syndrome (ES) remains controversial. The aim of this study is to systemically review the safety and effects of ERAs in improving the quality of life and basic cardiac functions of these patients.

METHODS

Twelve databases were searched, including PubMed, Web of Science, Scopus, Virtual Health Library, World Health Organization (WHO) Global Health Library, Google Scholar, POPLINE, Systems for Information of Grey Literature in Europe, New York Academy of Medicine, ClinicalTrials.gov, metaRegister of Controlled Trials and the WHO International Clinical Trials Registry Platform, through August 2016. We included randomized clinical trials addressing the effect of ERAs on cardiac functions in patients with ES. The quality of studies was assessed using the Cochrane Collaboration tool.

RESULTS

We included two trials represented by four papers, of which three papers reported the efficacy of bosentan against placebo and one paper reported the results of a combination of bosentan and sildenafil versus placebo and bosentan. One trial showed a significant effect of bosentan treatment over placebo on indexed pulmonary vascular resistance and mean pulmonary artery pressure, but a non-significant increase in 6-min walk distance and a non-significant effect on systemic pulse oximetry. The other trial reported the safe but non-significant effect of combination therapy of bosentan and sildenafil compared with bosentan and placebo.

CONCLUSIONS

This study demonstrated safety and improved hemodynamic effects of bosentan in ES, with a controversial effect on exercise capacity. Further randomized controlled trials with longer follow-up duration are needed to confirm these results.

The respiratory system in pediatric chronic heart disease

Cardiovascular disease in the pediatric population closely affects the respiratory system inducing water retention in the lungs and pulmonary edema, airway compression by cardiovascular structures, restrictive pulmonary physiology as a result of hemodynamic changes and surgical repair, susceptibility to respiratory infections, development of pulmonary hypertension, thrombosis, or hemorrhage. Chronic heart failure and congenital heart disease are characterized by various respiratory manifestations and symptoms mimicking lung disease, which are frequently difficult to diagnose and treat. Pulmonary function is multiply affected in pediatric heart disease with mostly restrictive but also obstructive and diffusion abnormalities. Patients with Fontan circulation represent a separate group with slow, passive pulmonary blood flow and distinct pathophysiology with low cardiac output heart failure, restrictive lung pattern, increased thromboembolic complications and rare conditions such as protein losing enteropathy and plastic bronchitis. Distinguishing between cardiovascular and pulmonary symptoms may be challenging in the growing population of pediatric and adult survivors of congenital heart disease and understanding of the relationship of the two systems in heart disease is crucial for the optimal management of these patients.

Diagnosis and Management of Noncardiac Complications in Adults With Congenital Heart Disease: A Scientific Statement From the American Heart Association

Life expectancy and quality of life for those born with congenital heart disease (CHD) have greatly improved over the past 3 decades. While representing a great advance for these patients, who have been able to move from childhood to successful adult lives in increasing numbers, this development has resulted in an epidemiological shift and a generation of patients who are at risk of developing chronic multisystem disease in adulthood. Noncardiac complications significantly contribute to the morbidity and mortality of adults with CHD. Reduced survival has been documented in patients with CHD with renal dysfunction, restrictive lung disease, anemia, and cirrhosis. Furthermore, as this population ages, atherosclerotic cardiovascular disease and its risk factors are becoming increasingly prevalent. Disorders of psychosocial and cognitive development are key factors affecting the quality of life of these individuals. It is incumbent on physicians who care for patients with CHD to be mindful of the effects that disease of organs other than the heart may have on the well-being of adults with CHD. Further research is needed to understand how these noncardiac complications may affect the long-term outcome in these patients and what modifiable factors can be targeted for preventive intervention.

Health-related quality of life of patients with pulmonary arterial hypertension associated with CHD: the multicentre cross-sectional ACHILLE study

BACKGROUND

The aim of this study was to assess health-related quality of life in patients with pulmonary arterial hypertension associated with CHD and correlations with clinical status.

METHODS

This prospective cross-sectional observational study included CHD patients with pulmonary arterial hypertension in 14 tertiary-care centres in France. We used two health-related quality of life questionnaires - SF-36 and Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) - and one anxiety/depression Hospital Anxiety and Depression Scale (HADS) questionnaire.

RESULTS

Clinical data were collected for the 208 included patients (mean age: 42.6 years, range from 15.1 to 85.8 years, 69.7% female). Most patients were in NYHA functional class II (48.1%) and III (37.5%). Patients' phenotype was classified as Eisenmenger syndrome (70.7%), pulmonary arterial hypertension associated with systemic-to-pulmonary shunts (12.0%), with small defects (3.4%), or after corrective cardiac surgery (13.9%). In total, 76.4% of the patients were receiving pulmonary arterial hypertension-specific treatments. SF-36 scores showed impairment compared with normalised data. Health-related quality of life scores were significantly lower in females than in males for most dimensions of both questionnaires and were independent of the patients' phenotype, even after gender adjustment - except for CAMPHOR functioning - but significantly depended on NYHA functional class. The Hospital Anxiety and Depression Scale (HADS) scores suggested anxiety and depression associated with increasing NYHA functional class but independent of patients' phenotype. NYHA functional class, 6-minute walk distance, HADS, gender, and recent stressful event significantly affected quality of life in the multivariate analysis.

CONCLUSIONS

This study showed impairment of quality of life in a large cohort of patients with pulmonary arterial hypertension associated with CHD with both generic and specific questionnaires. NYHA functional class and HADS scores were predictive of most quality of life scores.

Pulmonary arterial hypertension in congenital heart disease: Current perspectives and future challenges

Medical and scientific research in the field of pulmonary arterial hypertension (PAH) in adults with congenital heart disease (ACHD) has gradually become globalized, inclusive and collaborative over the past few years. The education of physicians, health administrators and patients on congenital heart disease (CHD), specifically in the field of PAH, is of paramount importance. It is also crucial for ACHD patients with PAH to be followed in tertiary centers and to benefit from a multidisciplinary approach. Shared care models dictate a closer collaboration between tertiary expert centers and local non-specialist services, as well as networking between expert physicians in CHD and PAH and geneticists/epidemiologists, with the inclusion of PAH-CHD patients in national and international registries with a detailed genotypic/phenotypic characterization.

Insight into Pulmonary Arterial Hypertension Associated with Congenital Heart Disease (PAH-CHD): Classification and Pharmacological Management from a Pediatric Cardiological Point of View

Compared with adult patients with pulmonary hypertension (PH), pulmonary vascular disease is characterized by complex heterogeneity in pediatric patients. The Nice PH classification does not completely characterize or individualize any subgroup of pediatric PH. This is in contrast to the Panama classification, in which prenatal and fetal origins of many pulmonary vascular diseases in neonates and children, perinatal pulmonary vascular maladaptation, prenatal and postnatal pulmonary vascular mal-development, and pulmonary vascular hypoplasia are included. Currently, the updated treatment algorithm for adults with pulmonary arterial hypertension (PAH), including PAH associated with congenital heart disease (PAH-CHD) and idiopathic PAH, etc. has been reported. It has been suggested to treat FC III patients with Eisenmenger syndrome (ES) with bosentan. However, there is no evidence-based treatment algorithm for children with PAH-CHD. Moreover, it is necessary to develop a more comprehensive algorithm in which multiple specific pediatric risk factors are determined, and the critical goal of treatment should be to permit normal activities without the need to self-limit in children with PAH-CHD. Together, the beneficial data on specific-target pharmacologic interventions are still quite preliminary, and large trials are warranted. Specifically, the extrapolation of the other forms of the disease, such as ES, should be undertaken carefully.

KEY WORDS

Congenital heart disease; Eisenmenger syndrome; Pulmonary arterial hypertension; Target therapy.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Pulmonary arterial hypertension associated with congenital heart disease

Congenital heart disease (CHD) with intracardiac/extracardiac shunts is an important etiology of pulmonary arterial hypertension (PAH). The majority of children with congenital cardiac shunts do not develop advanced pulmonary vasculopathy, as surgical repair of the anomalies is now performed early in life. However, if not repaired early, some defects will inevitably lead to pulmonary vascular disease (truncus arteriosus, transposition of the great arteries associated with a ventricular septal defect (VSD), atrioventricular septal defects remarkably in Down syndrome, large, nonrestrictive VSDs, patent ductus arteriosus and related anomalies). The majority of patients are now assigned to surgery based on noninvasive evaluation only. PAH becomes a concern (requiring advanced diagnostic procedures) in about 2-10% of them. In adults with CHD, the prevalence of advanced pulmonary vasculopathy (Eisenmenger syndrome) is around 4-12%.[1]

This article will discuss the diagnostic and management approach for PAH associated with CHD (PAH-CHD).

Ambrisentan therapy in pulmonary hypertension: clinical use and tolerability in a referral centre

INTRODUCTION

Ambrisentan is an oral selective endothelin receptor antagonist licensed for use in pulmonary arterial hypertension (PAH). There are few data on clinical use and long-term tolerability in a wider range of patients with pulmonary hypertension (PH).

METHODS

All patients treated with ambrisentan over a 4-year period were identified. Baseline characteristics, liver function test (LFT) results and World Health Organization (WHO) functional class were retrieved from hospital databases.

RESULTS

272 patients received ambrisentan between March 2009 and June 2013 (32% idiopathic PAH, 36% connective tissue disease PAH, 11% congenital heart disease PAH, 6% portopulmonary hypertension, 1% HIV PAH, 4% PH in association with lung disease, 8% chronic thromboembolic PH and 2% PH in association with sarcoidosis). 33.5% of patients received ambrisentan as monotherapy and 12% received ambrisentan as their initial PH therapy. 18% stopped treatment due to side effects and 12% stopped due to lack of efficacy. Oedema was the most common side effect leading to cessation of therapy, which occurred in 7% of patients. 57% of patients who discontinued ambrisentan due to side effects also discontinued other PAH therapies due to side effects previously or subsequently. Ambrisentan was discontinued in two (<1%) patients due to abnormal LFTs. The 3-year survival in congenital heart disease PAH, idiopathic PAH and systemic sclerosis-associated PAH was 80%, 62%, and 38%, respectively (p = 0.003). Survival was superior in patients in whom WHO functional class improved in response to therapy.

CONCLUSION

Ambrisentan is used as an initial therapy and as monotherapy in a minority of patients in a large UK PH referral centre. Discontinuation due to side effects, and especially oedema, was higher than reported in previous studies while discontinuation due to abnormal LFTs was very uncommon. A majority of patients who discontinued therapy due to side effects also previously or subsequently discontinued other PAH therapies. Improvement in WHO functional class was associated with superior survival.

Contemporary prevalence of pulmonary arterial hypertension in adult congenital heart disease following the updated clinical classification

BACKGROUND

The aging congenital heart disease (CHD) population is prone to develop a variety of sequelae, including pulmonary arterial hypertension (PAH). Previous prevalence estimates are limited in applicability due to the use of tertiary centers, or database encoding only. We aimed to investigate the contemporary prevalence of PAH in adult CHD patients, using a nationwide population.

METHODS

A cross-sectional study was performed, using the population-based Dutch CONgenital CORvitia (CONCOR) registry. All patients born with a systemic-to-pulmonary shunt, thereby at risk of developing PAH, were identified. From this cohort, a random sample was obtained and carefully reviewed.

RESULTS

Of 12,624 registered adults with CHD alive in 2011, 5,487 (44%) were at risk of PAH. The random sample consisted of 1,814 patients (mean age 40 ± 15 years) and 135 PAH cases were observed. PAH prevalence in patients born with a systemic-to-pulmonary shunt was 7.4%. The prevalence of PAH after corrective cardiac surgery was remarkably high (5.7%). Furthermore, PAH prevalence increased with age, from 2.5% under 30 years until 35% in the eldest. PAH prevalence in the entire CHD population was 3.2%. Based on 3000 per million adult CHD patients in the general population, we can assume that PAH-CHD is present in 100 per million.

CONCLUSIONS

This new approach using a nationwide CHD population reports a PAH prevalence of 3.2% in CHD patients, and 100 per million in the general adult population. Especially in patients after shunt closure and the elderly, physicians should be aware of PAH-CHD, to provide optimal therapeutic and clinical care.

Pulmonary hypertension related to congenital heart disease: a call for action

Pulmonary arterial hypertension related to congenital heart disease (PAH-CHD) is a common type of pulmonary arterial hypertension (PAH). Despite this, little emphasis has been given to this group of patients until recently, when compared with idiopathic PAH. This is largely because of the complexity and the wide range of underlying cardiac anatomy and physiology, with a multitude of adaptive mechanisms not fully understood. Pulmonary arterial hypertension related to congenital heart disease is, therefore, best diagnosed and managed in centres specializing in both CHD and PAH, to avoid common pitfalls and old practices and to provide state-of-the-art care. We discuss the optimal management of PAH-CHD patients in a series of actions to be taken in order to optimize short- and long-term outcome, based on current knowledge of the condition and the advent of targeted advanced therapies.

Congenital heart disease and pulmonary hypertension

Many patients with congenital heart disease and systemic-to-pulmonary shunts develop pulmonary arterial hypertension (PAH), particularly if the cardiac defect is left unrepaired. A persistent increase in pulmonary blood flow may lead to obstructive arteriopathy and increased pulmonary vascular resistance, a condition that can lead to reversal of shunt and cyanosis (Eisenmenger syndrome). Cardiac catheterization is crucial to confirm diagnosis and facilitate treatment. Bosentan is the only medication to date to be compared with placebo in a randomized controlled trial specifically targeting congenital heart disease-associated PAH. Lung transplantation with repair of the cardiac defect or combined heart-lung transplantation is reserved for recalcitrant cases.

Pulmonary complications of congenital heart disease

Cardiac and pulmonary pathophysiologies are closely interdependent, which makes the management of patients with congenital heart disease (CHD) all the more complex. Pulmonary complications of CHD can be structural due to compression causing airway malacia or atelectasis of the lung. Surgical repair of CHD can also result in structural trauma to the respiratory system, e.g., chylothorax, subglottic stenosis, or diaphragmatic paralysis. Disruption of the Starling forces in the pulmonary vascular system in certain types of CHD lead to alveolar-capillary membrane damage and pulmonary oedema. This in turn results in poorly compliant lungs with a restrictive lung function pattern that can deteriorate to cause hypoxemia. The circulation post single ventricle palliative surgery (the so called "Fontan circulation") poses a unique spectrum of pulmonary pathophysiology with restrictive lung function and a low pulmonary blood flow state that predisposes to thromboembolic complications and plastic bronchitis. As the population of patients surviving post CHD repair increases, the incidence of pulmonary complications has also increased and presents a unique cohort in both the paediatric and adult clinics.

Adult congenital heart disease and pulmonary arterial hypertension: the Texas Adult Congenital Heart Program experience

Congenital heart disease (CHD) is a common structural defect of the heart or major blood vessels. Patients with adult congenital heart disease (ACHD) have medical needs that are distinct from those of pediatric patients with CHD, and the transition into adult health care is important for management of the patient with ACHD. A large proportion of patients with CHD develop diseases and complications associated with the long-term stress of intracardiac shunts. Pulmonary arterial hypertension (PAH) is a significant complication of some CHD lesions. The treatment of these patients remains challenging due to their combined heart and lung disease, and multidisciplinary care is ofen necessitated for a variety of secondary conditions. A number of treatment options are available for the management of PAH associated with CHD, including prostanoids, phosphodiesterase type-5 inhibitors, and endothelin receptor antagonists. This article discusses the diagnosis and management of such ACHD patients with PAH.

Cardiac magnetic resonance imaging-derived pulmonary artery distensibility index correlates with pulmonary artery stiffness and predicts functional capacity in patients with pulmonary arterial hypertension

BACKGROUND

Increased stiffness of the pulmonary vascular bed is known to increase mortality in patients with pulmonary arterial hypertension (PAH); and pulmonary artery (PA) stiffness is also thought to be associated with exercise capacity. The purpose of the present study was to investigate whether cardiac magnetic resonance imaging (CMRI)-derived PA distensibility index correlates with PA stiffness estimated on right heart catheterization (RHC) and predicts functional capacity (FC) in patients with PAH.

METHODS AND RESULTS

Thirty-five consecutive PAH patients (23% male, mean age, 44 ± 13 years; 69% idiopathic) underwent CMRI, RHC, and 6-min walk test (6MWT). PA distensibility indices were derived from cross-sectional area change (%) in the transverse view, perpendicular to the axis of the main PA, on CMRI [(maximum area-minimum area)/minimum area during cardiac cycle]. Among the PA stiffness indices, pulmonary vascular resistance (PVR) and PA capacitance were calculated using hemodynamic dataset from RHC. CMRI-derived PA distensibility was inversely correlated with PVR (R²=0.34, P<0.001) and directly correlated with PA capacitance (R²=0.35, P<0.001), and the distance in the 6MWT (R²=0.61, P<0.001). Furthermore, PA distensibility <20% predicted poor FC (<400m in 6MWT) with a sensitivity of 82% and a specificity of 94%.

CONCLUSIONS

Non-invasive CMRI-derived PA distensibility index correlates with PA stiffness and can predict FC in patients with PAH.

Usefulness of natriuretic Peptide levels to predict mortality in adults with congenital heart disease

Neurohormonal activation is prevalent in adults with congenital heart disease, but its relation to outcome remains unknown. B-type natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) were measured prospectively in 49 patients with adult congenital heart disease, who were followed up for a median of 7.9 years (interquartile range 7.7 to 8.2). Cox proportional hazards regression analysis was used to determine the relation of BNP and ANP concentrations to all-cause mortality. The mean age at baseline was 33.9 +/- 11.3 years, and 46.9% of patients were men. Most patients (77.5%) were symptomatic (20.4% had New York Heart Association class III), 10 (20.4%) were cyanotic, and 28 (57.1%) had systemic ventricular dysfunction (moderate or severe in 18.4%). The median concentration of BNP was 52.7 pg/ml (interquartile range 39.1 to 115.4) and of ANP was 47.4 pg/ml (interquartile range 19.7 to 112.8). Of the 49 patients, 11 (22.4%) died during the follow-up period. Both BNP and ANP were strong predictors of mortality (hazard ratio per 100-pg/ml increase 1.80, 95% confidence interval 1.38 to 2.34, p <0.0001; and hazard ratio per 100-pg/ml increase 1.21, 95% confidence interval 1.12 to 1.32, p <0.0001, respectively). A BNP value >78 pg/ml predicted death with a sensitivity of 100% and specificity of 76.3% (area under the curve 0.91, p = 0.0001). An ANP value of >146 pg/ml predicted death with a sensitivity of 72.7% and specificity 94.7% (area under the curve 0.89, p = 0.0001). No patients with a BNP level <78 pg/ml died during the follow-up period. In conclusion, the BNP and ANP levels strongly predicted death in symptomatic ambulatory patients with adult congenital heart disease during mid-term follow-up and could be used as a simple clinical marker for risk stratification in this population.

[Eisenmenger syndrome. Pathophysiology]

Eisenmenger syndrome is the most feared complication by patients with congenital heart disorders with left-to-right shunt. This complication became rare in industrial countries thanks to optimized perinatal patient management and precocious elimination of the shunt. The presence of endothelial circulatory cells is a poor prognosis factor.

Improved Survival Among Patients With Eisenmenger Syndrome Receiving Advanced Therapy for Pulmonary Arterial Hypertension

Background— Advanced therapy (AT) for pulmonary arterial hypertension in the context of congenital heart disease (Eisenmenger syndrome) improves pulmonary hemodynamics, functional class, and the 6-minute walk test. We examined the potential effect of AT on survival in this population.

Methods and Results— Data on all Eisenmenger patients attending our center over the past decade were collected. Survival rates were compared between patients on and off AT with the use of a modified version of the Cox model, which treats AT as a time-varying covariate. Baseline differences were adjusted for the use of propensity scores. A total of 229 patients (aged 34.5±12.6 years; 35.4% male) were included. The majority had complex anatomy, and 53.7% were in New York Heart Association class ≥III at baseline assessment. Mean resting saturations were 84.3%. Sixty-eight patients (29.7%) either were on AT or had AT initiated during follow-up. During a median follow-up of 4.0 years, 52 patients died, only 2 of them while on AT. Patients on AT were at a significantly lower risk of death, both unadjusted and after adjustment for baseline clinical differences by propensity score regression adjustment ( C statistic=0.80; hazard ratio, 0.16; 95% confidence interval, 0.04 to 0.71; P =0.015) and propensity score matching (hazard ratio, 0.10; 95% confidence interval, 0.01 to 0.78; P =0.028).

Conclusions— AT for pulmonary arterial hypertension in a contemporary cohort of adults with Eisenmenger syndrome was associated with a lower risk of death. Survival benefits should be considered together with improved hemodynamics and functional class when decisions are made about AT in this population.

Clinical practice. The impact of lung disease on the heart and cardiac disease on the lungs

Pathologies in both the respiratory and cardiovascular systems frequently coexist and impact on each other. This manuscript introduces an approach to the interpretation of this complex relationship. Pulmonary hypertension can be a significant consequence of many respiratory diseases. This in turn can lead to right ventricular dysfunction and cor pulmonale. Many childhood illnesses can result in cor pulmonale and can be conveniently grouped into three categories: idiopathic pulmonary hypertension, neonatal lung diseases, and lung disease beyond the neonatal period. When considering the impact of cardiac disease on the lung, one must consider two main pathologies: compression of the pediatric airway and increased lung water. In conclusion, thorough attention must be given to the interpretation of the complex relationship between cardiac and respiratory diseases. Pulmonary hypertension is a complication to consider in respiratory illness at all ages. In addition, when dealing with the complexities of congenital heart disease, one must always be aware of the risks of pulmonary complications whether parenchymal or airway. Ongoing improvements in ventilation strategies, vasodilator therapy, and surgical interventions continue to improve the outlook for these complex cases.