Pulmonary Arterial Hypertension Associated With Congenital Heart Disease Research Articles

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).

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Pulmonary hypertension in children.

Pulmonary hypertension (PH) is relatively uncommon in children. Pulmonary arterial hypertension (PAH) in pediatric comprises a wide spectrum of diseases, from a transient neonatal condition to a progressive disease associated with morbidity and mortality. Most common PAH in pediatric are idiopathic (IPAH) or PAH associated with congenital heart disease (PAH-CHD), while other associated conditions, such as connective tissue disease (CTD), are less common in pediatrics. Despite better understanding of PH and the availability of new medications during recent decades; the diagnosis, investigation and choice of therapy remain a challenge in children, as evidence-based recommendations depend mainly on adult studies.In this review, we provide a detailed discussion about the distinctive features of PAH in pediatric, mainly emphacysing on classification and diagnostic algorithm.

The Essential Role of Imaging in the Evaluation of Patients With Pulmonary Arterial Hypertension in Association With Congenital Heart Disease

Pulmonary arterial hypertension (PAH) is a hemodynamic and pathophysiologic condition defined as an increase in mean pulmonary artery pressure (MPAP) of ≥25 mm Hg at rest measured at right heart catheterization (RHC).12 Patients with PAH associated with congenital heart disease (PAH-CHD) are a growing population consisting of an anatomically and phenotypically heterogeneous group, where differences among specific cardiac defects, along with their varied clinical course and prognosis, influence treatment choices for the individual patient.

Current era survival of patients with pulmonary arterial hypertension associated with congenital heart disease: a comparison between clinical subgroups

This study compared the clinical, functional, and haemodynamic characteristics and current era survival of subgroups of patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD): Eisenmenger syndrome (ES); PAH-CHD associated with systemic-to-pulmonary shunts (SPs); PAH with small defects (SDs); and PAH after defect correction (CDs). Data from consecutive PAH-CHD patients referred to our centre from 1 January 1998 to 31 May 2011 were collected. A contemporary group of idiopathic PAH patients was utilized for comparison. Treatment was per PAH guidelines, including combination therapy, with approved PAH-specific drugs. Survival was assessed with Kaplan-Meier analysis from the first invasive haemodynamic confirmation of PAH and compared across subgroups by log-rank test. Of 192 patients (mean age 41 ± 17 years; 61% female), 90 had ES (aged 41 ± 16 years); 48 SP (aged 47 ± 18 years); 10 SD (aged 25 ± 21 years); and 44 CD (aged 36 ± 17 years). Patients with ES had the highest baseline pulmonary vascular resistance and the lowest exercise capacity. Seventy-eight per cent were treated with approved PAH-specific drugs, and 44% were treated with combination therapy. Kaplan-Meier survival estimates (95% confidence interval) at 20 years for ES, SP, and CD were 87% (77-93%), 86% (60-96%), and 36% (12-72%, P = 0.0001 vs. ES; P = 0.004 vs. SP), respectively, and at 15 years for SD was 66% (16-91%, P = 0.015 vs. ES; P = 0.016 vs. SP). The survival of the 278 patients with idiopathic PAH appeared to be worse when compared with the PAH-CHD subgroups. Relevant clinical, functional, haemodynamic, and survival differences were observed among subgroups. In particular, patients with CD and SD had the worst survival. These findings should be considered when planning medical or interventional treatment strategies in PAH-CHD patients.

Elevated Homocysteine and Asymmetric Dimethyl Arginine Levels in Pulmonary Hypertension Associated With Congenital Heart Disease

Pulmonary arterial hypertension (PAH) is a major cause of morbidity and mortality among patients with congenital heart disease (CHD). This study was designed to determine biomarker levels in patients with PAH associated with CHD (PAH-CHD) and CHD patients without PAH and to investigate the relationship of these potential biomarkers with hemodynamic findings. In this prospective single-center study, patients with CHD were analyzed according to the presence or absence of PAH and compared with healthy control subjects. Cardiac catheterization and echocardiographs were performed. Plasma homocysteine, asymmetric dimethyl arginine (ADMA), and nitric oxide (NO) levels were determined by enzyme-linked immunosorbent assay. Homocysteine and ADMA levels were higher in the PAH-CHD group (n = 30) than among CHD patients with left-to-right shunting but no PAH (n = 20; P < 0.001) and healthy control subjects (n = 20; P < 0.001). There was no difference in NO levels. Cyanotic PAH-CHD patients had significantly higher homocysteine than acyanotic patients in the same group. No correlation was shown between echocardiographic/hemodynamic parameters and homocysteine, ADMA, and NO levels. Homocysteine and ADMA levels are increased in patients with PAH-CHD. These parameters have the potential to be used as biomarkers in the diagnosis and follow-up evaluation of patients with PAH-CHD. However, large, multicentered prospective studies are required to facilitate routine use of these biologic markers in the clinical setting.

Acute pulmonary vasodilator response in paediatric and adult pulmonary arterial hypertension: occurrence and prognostic value when comparing three response criteria

To assess the occurrence and prognostic value of acute vasodilator response (AVR) in paediatric vs. adult pulmonary arterial hypertension, and idiopathic/hereditary pulmonary arterial hypertension (iPAH/HPAH) vs. pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) using three different response criteria. Ninety-nine PAH patients underwent AVR testing (37 children, 62 adults; 70 iPAH/HPAH, 29 PAH-CHD). Three response criteria from clinical practice were used to define AVR. The number of responders was evaluated separately in subgroups based on age, diagnosis, and presence of a non-restrictive post-tricuspid shunt. Numbers of responders varied importantly using the different criteria but were always higher in iPAH/HPAH, compared with PAH-CHD. The number of responders did not differ between paediatric and adult iPAH/HPAH. No responders were identified in patients with a post-tricuspid shunt. Acute vasodilator response was associated with improved survival using all three criteria. Low baseline mean right atrial pressure (mRAP) was associated with improved survival in adults (P< 0.001). High baseline mean pulmonary arterial pressure (mPAP)/mean systemic arterial pressure (mSAP) and pulmonary vascular resistance (PVR)/systemic vascular resistance (SVR) were associated with worse survival, statistically independent from age, diagnosis, and the presence of a post-tricuspid shunt. The proportion of patients with AVR highly depends on the used criteria, but did not differ between paediatric and adult iPAH/HPAH. Current response criteria are not suitable for patients with a post-tricuspid shunt. In both children and adults without post-tricuspid shunts, AVR was associated with improved survival independent of the used criteria. Nevertheless, prognostic value in the individual patient was limited. Baseline mRAP showed a good correlation with survival for adult PAH patients, but not for children. High baseline mPAP/mSAP and PVR/SVR was associated with worse prognosis independent from age, diagnosis, or the presence of a post-tricuspid shunt.

Endothelin Receptor Antagonists are an Effective Long Term Treatment Option in Pulmonary Arterial Hypertension Associated with Congenital Heart Disease With or Without Trisomy 21

Traditionally, treatment options for patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) are limited. Bosentan has been shown to improve pulmonary haemodynamics and exercise tolerance short term but long term clinical studies are lacking. To report long term efficacy and safety data with endothelin receptor antagonists (ERA) in patients with PAH associated CHD. Prospective, open label, uncontrolled, single centre study of 53 patients (33 females, 17 Trisomy 21, mean age 34 ± 12 years) prescribed ERA (48 bosentan, 5 sitaxentan) from 2003 to August 2009. Outcome measurements of oxygen saturation (SaO2), WHO functional class, 6-minute walk test distance (6MWD) and adverse events were analysed. Mean duration of therapy was 15 ± 13 months in 53 patients with CHD. Four patients failed ERA, seven died (five progressive RHF) and one delisted from transplantation. No abnormal liver transaminases occurred on bosentan, with one case on sitaxentan. After 3, 6, 12, 18 and 24 months of treatment a significant improvement was seen in WHO functional class (mean 3.15 vs 2.8 vs 2.5 vs 2.5 vs 2.4 vs 2.4; p<0.01) and 6MWD (344 ± 18 vs 392 ± 17 vs 411 ± 17 vs 420 ± 17 vs 442 ± 18 vs 417 ± 23: p<0.0005, p<0.01) compared with baseline. The Trisomy 21 and PAH-CHD showed a significant improvement in 6MWD at 6 and 12 months (263 ± 24 vs 348 ± 29 vs 360 ± 32, p<0.01, p<0.05) respectively. No changes in SaO2, BNP, RV or LV function were demonstrated during follow-up. This large single centre study demonstrates that endothelin receptor antagonism is an effective and safe treatment in PAH associated CHD with or without Trisomy 21. The improvements in exercise tolerance are similar to reported benefits in other forms of PAH.

Pulmonary arterial hypertension in paediatric and adult patients with congenital heart disease

Pulmonary arterial hypertension (PAH) commonly arises in patients with congenital heart disease (CHD). Greater numbers of patients with PAH associated with CHD (PAH-CHD) are now surviving into adulthood, many with increasingly complex cardiac defects. Patients with cardiac defects which result in left-to-right shunting are at risk of developing PAH, owing to the increased shear stress and circumferential stretch induced by increased pulmonary blood flow, which leads to endothelial dysfunction and progressive vascular remodelling and, thus, increased pulmonary vascular resistance. Although PAH-CHD shares similar lung histology with idiopathic PAH, differences do exist between these aetiologies. Management of PAH-CHD can involve surgical correction of the cardiac defect and/or treatment of the PAH, depending on the underlying cardiac defect and status of disease progression. Transplantation surgery can be curative but is not without limitations. The timing of intervention in patients with PAH-CHD is important, but the optimums are sometimes difficult to define, with limited robust data to inform management decisions. Uncontrolled studies suggest that prostacyclin analogues and phosphodiesterase type-5 inhibitors may have benefits in advanced pulmonary vascular disease. In the only randomised controlled trial dedicated to end-stage PAH-CHD, bosentan significantly reduced pulmonary vascular resistance and significantly increased 6-minute walk distance without compromising peripheral oxygen saturation, in patients with Eisenmenger syndrome. These data suggest that targeted therapies are beneficial in the PAH-CHD population, and warrant further research.

Adult patients with congenital heart disease and pulmonary arterial hypertension: First open prospective multicenter study of bosentan therapy

Endothelin receptor antagonism has been introduced as an effective oral therapy of patients with idiopathic pulmonary arterial hypertension. In view of the pathophysiologic and histologic similarities between idiopathic pulmonary arterial hypertension and pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD), there is a rationale for treating these patients with the oral dual (ET(A)/ET(B)) endothelin receptor antagonist bosentan. Thirty-three patients with PAH-CHD (43 +/- 14 years, 23 with Eisenmenger syndrome) were treated with bosentan for a mean of 2.1 +/- 0.5 years. Efficacy was assessed by a panel of tests, including New York Heart Association functional class, 6-minute walking distance, and echocardiographic and hemodynamic parameters. Mean 6-minute walking distance increased from 362 +/- 105 to 434 +/- 68 m (P = .001). New York Heart Association class also improved significantly (3.1 to 2.4, P = .0001). This was associated with slight trends in improvements of transcutaneous oxygen saturation (86% +/- 7% to 88% +/- 7%, P = .13) and maximum oxygen uptake (13.2 +/- 4.0 to 14.9 +/- 2.5, P = .18). Right ventricular systolic pressure measured by echocardiographic decreased from 111 +/- 32 to 106 +/- 22 mm Hg (P = .001). Bosentan treatment was well tolerated by all patients. Long-term bosentan treatment in adult patients with PAH-CHD was well tolerated and improved functional status as well as exercise capacity. These findings have to be corroborated by controlled studies that are presently ongoing.