Surgical and transcatheter management alternatives in refractory pulmonary hypertension: Potts shunt

Interventional and Surgical Treatments for Pulmonary Arterial Hypertension

Despite significant advancements in pharmacological treatment, interventional and surgical options are still viable treatments for patients with pulmonary arterial hypertension (PAH), particularly idiopathic PAH. Herein, we review the interventional and surgical treatments for PAH. Atrial septostomy and the Potts shunt can be useful bridging tools for lung transplantation (Ltx), which remains the final surgical treatment among patients who are refractory to any other kind of therapy. Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) remains the ultimate bridging therapy for patients with severe PAH. More importantly, VA-ECMO plays a crucial role during Ltx and provides necessary left ventricular conditioning during the initial postoperative period. Pulmonary denervation may potentially be a new way to ensure better transplant-free survival among patients with the aforementioned disease. However, high-quality randomized controlled trials are needed. As established, obtaining the Eisenmenger physiology among patients with severe pulmonary hypertension by creating artificial defects is associated with improved survival. However, right-to-left shunting may be harmful after Ltx. Closure of the artificially created defects may carry some risk associated with cardiac surgery, especially among patients with Potts shunts. In conclusion, PAH requires an interdisciplinary approach using pharmacological, interventional, and surgical modalities.

Potts shunt as an effective palliation for patients with end stage pulmonary arterial hypertension

BACKGROUND

Potts shunt has been suggested as an effective palliative therapy for patients with pulmonary artery hypertension (PAH) not associated with congenital heart disease.

MATERIALS AND METHODS

This is a prospective single-center study performed to assess outcomes of Potts shunt in patients with PAH who are in functional class III or IV.

RESULTS

52 patients in functional class III/IV with pulmonary arterial hypertension without significant intra or extracardiac shunt on maximal medical therapy were evaluated and counseled for undergoing Potts shunt/patent ductus arteriosus (PDA) stenting. 16/52 patients (13 females) consented for the procedure; 14 patients underwent surgical creation of Potts, and 2 underwent transcatheter stenting of PDA, which physiologically acted like a Potts shunt. Standard medical therapy was continued in patients who did not consent for the procedure. 12/16 patients survived the procedure. Patients who did not survive the procedure were older, with severe right ventricular systolic dysfunction, and functional class IV. Patients who survived the procedure were followed up in the pulmonary hypertension clinic. The Median follow-up was 17 months (1-40 months). 11/13 patients discharged after the operation showed sustained clinical, echocardiographic, and biochemical improvement, which reduced need for pulmonary vasodilator therapy in 10/13 patients. There was one death in the follow-up period 16 months post-surgery due to lower respiratory tract infection.

CONCLUSION

Potts shunt is feasible in patients with PAH without significant intra or extracardiac shunts. It can be done safely with an acceptable success rate. Patient selection, preoperative stabilization, and meticulous postoperative management are essential. It should be performed at the earliest sign of clinical, echocardiographic, or laboratory deterioation for optimal outcomes. Long-term follow-up is required to see a sustained improvement in functional class and the need for a lung transplant in the future.

An update on the diagnosis and treatment of pediatric pulmonary hypertension

INTRODUCTION

Pulmonary hypertension (PH) is a heterogeneous disease that mainly affects the pulmonary arterioles, leading to significant morbidity and mortality. Pulmonary hypertension in children from birth to adolescence presents important differences from that of adults. The majority of pediatric pulmonary arterial hypertension (PAH) cases are idiopathic or associated with congenital heart disease. However, the management of pediatric PAH mainly depends on the results of evidence-based adult studies and the clinical experiences of pediatric experts.

AREAS COVERED

This article briefly reviews the recent updates on the definition, classification, and diagnostic evaluation of pediatric PAH and their impact on treatment strategies. The main purpose of this review is to discuss the current pediatric therapies, as well as the prospective therapies, in terms of therapeutic targets, actions, side effects, and dosages.

EXPERT OPINION

Although there is no cure for PAH, recent advances in the form of new treatment options have improved the quality of life and survival rates of PAH patients. PAH-targeted drugs and treatment strategies for adult PAH have not been sufficiently studied in children. However, the growing scientific activity in that field will surely change the treatment option recommendations in pediatric PH from experience-based to evidence-based in the near future.

Idiopathic, heritable and veno-occlusive pulmonary arterial hypertension in childhood: computed tomography angiography features in the initial assessment of the disease

BACKGROUND

In children, idiopathic and heritable pulmonary arterial hypertension present echocardiographic and heart catheterization findings similar to findings in pulmonary veno-occlusive disease.

OBJECTIVE

To provide a systematic analysis of CT angiography anomalies in children with idiopathic or heritable pulmonary arterial hypertension, or pulmonary veno-occlusive disease. We also sought to identify correlations between CT findings and patients' baseline characteristics.

MATERIALS AND METHODS

We retrospectively analyzed CT features of children with idiopathic and heritable pulmonary arterial hypertension or pulmonary veno-occlusive disease and 30 age-matched controls between 2008 and 2014. We compared CT findings and patient characteristics, including gene mutation type, and disease outcome until 2017.

RESULTS

The pulmonary arterial hypertension group included idiopathic (n=15) and heritable pulmonary arterial hypertension (n=11) and pulmonary veno-occlusive disease (n=4). Median age was 6.5 years. Children with pulmonary arterial hypertension showed enlargement of pulmonary artery and right cardiac chambers. A threshold for the ratio between the pulmonary artery and the ascending aorta of ≥1.2 had a sensitivity of 90% and a specificity of 100% for pulmonary arterial hypertension. All children with pulmonary veno-occlusive disease had thickened interlobular septa, centrilobular ground-glass opacities, and lymphadenopathy. In children with idiopathic and heritable pulmonary arterial hypertension, presence of intrapulmonary neovessels and enlargement of the right atrium were correlated with higher mean pulmonary artery pressure (P=0.011) and pulmonary vascular resistance (P=0.038), respectively. Mediastinal lymphadenopathy was associated with disease worsening within the first 2 years of follow-up (P=0.024).

CONCLUSION

CT angiography could contribute to early diagnosis and prediction of severity in children with pulmonary arterial hypertension.

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.

Noteworthy Literature Published in 2016

This article is a review of the literature published during the 12 months of 2016 that are of interest to the congenital cardiac anesthesiologist. Five themes are addressed for 2016, and 53 peer-reviewed articles are discussed.