Pulmonary Vein Stenosis: Moving From Past Pessimism to Future Optimism.

Pulmonary Vein Stenosis (PVS) is a rare disease with a prevalence of around 1. 7 cases per 100,000 children under 2 years old. Treatment options for this disease have not provided great results and pathophysiology of this condition is still poorly understood. Here, we will review the history of PVS including diagnostic tools and treatments, the current management approach, and what the future holds for this devastating disease.

Pulmonary-to-Systemic Arterial Shunt to Treat Children With Severe Pulmonary Hypertension.

BACKGROUND: The placement of a pulmonary-to-systemic arterial shunt in children with severe pulmonary hypertension (PH) has been demonstrated, in relatively small studies, to be an effective palliation for their disease. OBJECTIVES: The aim of this study was to expand upon these earlier findings using an international registry for children with PH who have undergone a shunt procedure. METHODS: Retrospective data were obtained from 110 children with PH who underwent a shunt procedure collected from 13 institutions in Europe and the United States. RESULTS: Seventeen children died in-hospital postprocedure (15%). Of the 93 children successfully discharged home, 18 subsequently died or underwent lung transplantation (20%); the mean follow-up was 3.1 years (range: 25 days to 17 years). The overall 1- and 5-year freedom from death or transplant rates were 77% and 58%, respectively, and 92% and 68% for those discharged home, respectively. Children discharged home had significantly improved World Health Organization functional class (P < 0.001), 6-minute walk distances (P = 0.047) and lower brain natriuretic peptide levels (P < 0.001). Postprocedure, 59% of children were weaned completely from their prostacyclin infusion (P < 0.001). Preprocedural risk factors for dying in-hospital postprocedure included intensive care unit admission (hazard ratio [HR]: 3.2; P = 0.02), mechanical ventilation (HR: 8.3; P < 0.001) and extracorporeal membrane oxygenation (HR: 10.7; P < 0.001). CONCLUSIONS: A pulmonary-to-systemic arterial shunt can provide a child with severe PH significant clinical improvement that is both durable and potentially free from continuous prostacyclin infusion. Five-year survival is comparable to children undergoing lung transplantation for PH. Children with severely decompensated disease requiring aggressive intensive care are not good candidates for the shunt procedure.

Pulmonary Hypertension as a Complication of Pediatric Cancer.

Pediatric cancer is a life threatening disease known to create multi-organ complications that further compromise medical management affecting patient morbidity and mortality. Pulmonary hypertension (PH) is becoming more recognized as a complication of cancer and its therapies but has not been well characterized in pediatrics. Cancer pathophysiology can be uniquely set up to promote pulmonary vascular injury and remodeling that is similar to PH patients without cancer. This highlights the need to evaluate for PH clinically and with routine testing such as echocardiography during the course of a patient's care even into adulthood. This review article will discuss the direct, indirect and therapy related aspects of cancer which can promote PH in these patients. This understanding is essential to target effective treatment options in a potentially fatal complication. Diagnostic and treatment algorithms are presented in relation to the most recent pediatric PH management guidelines.

Oral treprostinil in transition or as add-on therapy in pediatric pulmonary arterial hypertension.

Treprostinil, a prostacyclin analogue, is approved for the treatment of pulmonary arterial hypertension (PAH) in adults. Transition from parenteral to oral treprostinil has been successfully accomplished in adults with PAH but not in children. In this multicenter study, pediatric patients treated with parenteral (Cohort 1) or inhaled (Cohort 2) treprostinil were transitioned to oral treprostinil. Prostacyclin-naïve individuals on background oral PAH therapy received oral treprostinil as add-on therapy (Cohort 3). Successful transition was oral treprostinil dose maintenance through week 24. Patients were monitored for adverse events (AEs), 6-min walk distance (6MWD), PAH symptoms, World Health Organization (WHO) Functional Class (FC), cardiac magnetic resonance imaging (cMRI), cardiopulmonary exercise testing (CPET), and quality of life through 24 weeks. A total of 32 patients were enrolled in the study; 23 (72%) were girls (mean age = 12.2 years). All patients were on background oral PAH therapy. Overall, patients (96.9%) maintained transition to oral treprostinil; one patient (Cohort 1) transitioned to oral treprostinil, then back to parenteral after experiencing syncope and WHO FC change from II to III. Cohorts 1, 2, and 3 received a final mean oral treprostinil dose of 5.6, 3.3, and 4.5 mg t.i.d., respectively. All cohorts had variable changes in 6MWD, cMRI, and CPET. Overall, 12 serious AEs were reported. All patients had drug-related AEs including headache (81%), diarrhea (69%), nausea (66%), vomiting (66%), and flushing (56%). Pediatric patients maintained transition to oral treprostinil with preservation of exercise capacity and WHO FC. Prostanoid-related AEs were most common and similar to those reported in adults.

Assessment of quality of life in pediatric patients with pulmonary hypertension.

The aim of this study is to evaluate quality of life in four domains (physical, emotional, social, and school) in pediatric patients with pulmonary hypertension (PH) using a validated survey (PedsQL). This is a prospective cohort study of pediatric patients aged 2-18 years with PH. Parents of all children and patients aged 8-18 years with appropriate developmental capacity completed the PedsQL survey in the clinic. Results were compared with published norms for pediatric patients, those with congenital heart disease (CHD) and cancer. Thirty-three children were enrolled yielding 32 parent and 18 patient self-reports: seven patients were aged 2-4 years; three were aged 5-7 years; 11 were aged 8-12 years, and 12 were aged 13-18 years. Twenty-one patients were classified as World Health Organization (WHO) Group I pulmonary arterial hypertension (PAH), 11 WHO Group III PH due to lung disease, and one WHO Group V with segmental PH. Thirteen patients were NYHA functional class (FC) 1, 12 were FC 2, eight were FC 3, and none were FC 4. The PH cohort had significantly lower scores than healthy children in all domains on both parent and self-report. The PH cohort also had significantly lower scores than patients with CHD (parent report: total, physical, social, school; patient self-report: total, physical, school) and cancer (parent report: school; patient self-report: physical, school). Close to 50% of participants reported at risk scores in each domain. The quality of life in pediatric PH patients assessed by PedsQL revealed functional impairment in multiple domains. Administration of the PedsQL during outpatient encounters may provide an easy, reproducible method to assess quality of life and direct referral for interventional services.

Pulmonary Vein Doppler Patterns in Infants with Single Right Ventricle Anomalies After Initial Staged Palliations.

The aim of this study was to describe serial changes in echocardiographic Doppler pulmonary vein flow (PVF) patterns in infants with single right ventricle (RV) anomalies enrolled in the Single Ventricle Reconstruction trial. Measurement of PVF peak systolic (S) and diastolic (D) velocities, velocity time integrals (VTI), S/D peak velocity and VTI ratios, and frequency of atrial reversal (Ar) waves were made at three postoperative time points in 261 infants: early post-Norwood, pre-stage II surgery, and 14 months. Indices were compared over time, between initial shunt type [modified Blalock-Taussig shunt (MBTS) and right ventricle-to-pulmonary artery shunt (RVPAS)] and in relation to clinical outcomes. S velocities and VTI increased over time while D wave was stable, resulting in increasing S/D peak velocity and VTI ratios, with a median post-Norwood S/D VTI ratio of 1.14 versus 1.38 at pre-stage II and 1.89 at 14 months (P < 0.0001 between intervals). MBTS subjects had significantly higher S/D peak velocity and VTI ratios compared to RVPAS at the post-Norwood and pre-stage II time points (P < 0.0001) but not by 14 months. PVF patterns did not correlate with survival or hospitalization course at 1 year. PVF patterns after Norwood palliation differ from normal infants by having a dominant systolic pattern throughout infancy. PVF differences based upon shunt type resolve by 14 months and did not correlate with clinical outcomes. This study describes normative values and variations in PVF for infants with a single RV from shunt-dependent pulmonary blood flow to cavopulmonary blood flow.

An Unusual Case of Severe Stenosis of the Coronary Sinus Ostium in Association With Double Inlet Left Ventricle.

We present a patient with complex single ventricle physiology who was subsequently diagnosed with atresia of the coronary sinus ostium in the setting of myocardial dysfunction following operative palliation. Although a rare cardiac defect, awareness is important as the coronary venous system will often drain to a left superior vena cava (LSVC). If the LSVC is ligated without knowing of this defect, cardiac dysfunction and death can occur.

Echocardiography in pediatric pulmonary hypertension.

Pediatric pulmonary hypertension is a complicated disease with multiple etiologies and high mortality. Echocardiography is at the forefront of evaluation as a noninvasive, portable imaging modality that can yield diagnostic and prognostic information regarding this disease. Echocardiography is known for its ability to give an anatomic assessment of the heart and proximal blood vessels. With the additional use of Doppler echocardiography and myocardial motion assessment, the effects of elevated pulmonary pressures on the heart can be evaluated. This can allow for estimation of pulmonary artery pressures and resistances and assessment of ventricular systolic and diastolic functions. However despite its advantages, echocardiography is still an indirect assessment of pulmonary hypertension and not a substitute for cardiac catheterization. The purpose of this review is to discuss common techniques for the assessment of pulmonary hypertension by echocardiography as well as their limitations.