Management of systemic to pulmonary shunts and elevated pulmonary vascular resistance.

Background: Repair of systemic to pulmonary shunts is timed to prevent the development of irreversible pulmonary vascular disease, including in patients with other factors contributing to pulmonary hypertension. This study assessed outcomes of an individualised strategy for managing patients with mild-moderately elevated pulmonary vascular resistance (PVR) deemed borderline eligible for repair. Methods: A retrospective chart review was conducted of patients with systemic to pulmonary shunts and baseline indexed PVR (PVRi) ≥3 WU·m2 treated at a single centre from 1 January 2005 to 30 September 2019. Data included demographics, World Health Organization functional class (WHO FC), medications and haemodynamic data at baseline and serial follow-up. Results: 30 patients (18 females) met criteria for inclusion. Median age at diagnosis of pulmonary arterial hypertension was 1.3 years (range 0.03-54 years) and at surgery was 4.1 years (range 0.73-56 years). Median follow-up time was 5.8 years (range 0.2-14.6 years) after repair. Most patients received at least one targeted pulmonary arterial therapy prior to repair and the majority (80%) underwent fenestrated shunt closure. There was a significant decrease in mean pulmonary arterial pressure (mPAP) (p<0.01), PVRi (p=0.0001) and PVR/systemic vascular resistance (p<0.01) between baseline and preoperative catheterisation and a decrease in PVRi (p<0.005), mPAP (p=0.0001) and pulmonary to systemic flow ratio (p<0.03) from baseline to most recent catheterisation. WHO FC improved from FC II-III at baseline to FC I post repair in most patients (p<0.003). Conclusions: In carefully selected patients with systemic to pulmonary shunts and elevated PVR considered borderline for operability, the use of preoperative targeted therapy in conjunction with fenestrated or partial closure of intracardiac shunts is associated with improvement in WHO FC and clinical outcomes.

Changes in Body Mass Index in Children and Adolescents with Asthma during the COVID-19 Pandemic.

Background: Increased weight gain in children during the COVID-19 pandemic has been reported. Changes in weight in children with asthma during this period have not been well described. Methods: Retrospective review of children with asthma, 6-18 years of age, seen in 2019 and 2020. Mean monthly rates of change in body mass index (BMI) were compared between years. Demographic and asthma-related factors were examined. Results: Two hundred sixty-seven patients were enrolled. BMI increased by 0.128 ± 0.283 kg/m2/month during the pandemic year as compared with 0.084 ± 0.160 kg/m2/month during the previous year (P = 0.03). Patients with baseline overweight or obesity trended toward higher rates of BMI increase than those starting with normal weight, with the greatest BMI increase occurring in the severely obese. Conclusions: In this single-site study of children with asthma, there was a greater monthly rate of BMI gain during the early pandemic as compared with that observed in the previous year.

Vasoreactive phenotype in children with pulmonary arterial hypertension and syncope.

Background: Syncope in Group 1 pulmonary arterial hypertension (PAH) is an independent predictor of poor prognosis in adults, but this is not well studied in children. We hypothesise that syncope in children with PAH often occurs in association with a reactive pulmonary vascular bed with sudden vasoconstriction in response to adverse stimuli. In the current study, we sought to determine the association of syncope with acute vasoresponsiveness and outcomes in children with Group 1 PAH. Methods: A retrospective chart review of children with PAH at a single pulmonary hypertension centre from 1 January 2005 to 31 October 2018 was performed. Data included demographics, symptoms, imaging, haemodynamics, and outcomes at baseline and follow-up. Results: 169 children had Group 1 PAH; 47 (28%) had syncope at presentation or follow-up. Children with significant shunts were excluded from the analysis. Children with syncope were older at diagnosis (7.5 versus 5.0 years; p=0.002) and had a higher incidence of chest pain (p=0.022) and fatigue (p=0.003). They had higher pulmonary vascular resistance at baseline (14.9 versus 9.1 WU·m2; p=0.01). More children with syncope were vasoresponders to inhaled nitric oxide (33% versus 22%; p=0.08-NS). Children with syncope and acute vasoresponsiveness had the highest survival, and non-responders with syncope on medications had the worst long-term survival. Conclusions: Children with syncope had higher rates of vasoreactivity compared to those without. This suggests that in some children with PAH, syncope may simply reflect acute pulmonary vasoconstriction to an adverse stimulus. Larger prospective studies are warranted to further assess syncope as a marker for a vasoreactive phenotype with implications for treatment and long-term outcomes.