RESUMEN
Parenteral prostanoid therapy (PPT) can result in supranormal cardiac index (SCI; >4 L/min/m2) in pediatric pulmonary hypertension (PPH) patients. We evaluated the incidence, hemodynamic factors, and outcomes associated with SCI in PPH. This retrospective cohort study included 22 PPH patients on PPT from 2005 to 2020. Hemodynamic profiles were compared between the baseline and 3-6 month follow-up catheterization in the SCI and non-SCI cohorts. Cox regression analysis examined time to composite adverse outcome (CAO; Potts shunt, lung transplant, or death) controlling for initial disease severity. SCI developed in 17 (77%) patients, of whom 11 (65%) developed SCI within 6 months. The SCI cohort was characterized by significant augmentation of cardiac index (CI) and stroke volume (SV) as well as reductions in systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR). Conversely, the non-SCI cohort had unchanged SV despite a modest rise in CI as well as persistent vasoconstriction. After median follow-up of 4.3 years (range 0.2-13 years), non-SCI patients were at significantly increased risk for the CAO (5/5: three deaths, two Potts shunts) compared with SCI patients (5/17: two deaths, three lung transplants; adjusted hazard ratio 14.0 [95% confidence interval: 2.1-91.3], p < 0.001). A majority of PPH patients developed SCI within 6-12 months of starting PPT and demonstrated lower risk of adverse outcomes compared with non-SCI patients. These data suggest that change in SVR and SV after 3-6 months of PPT may be early markers of therapeutic response and prognosis.
RESUMEN
OBJECTIVE: Congenital diaphragmatic hernia (CDH) survivors are at risk for long-term exercise impairment and pulmonary morbidity, but the generalizability of prior reported cohorts are limited by reduced disease severity and older surgical eras. We assessed the mid-childhood exercise and pulmonary function outcomes in a contemporary cohort of CDH survivors. STUDY DESIGN: In this retrospective cohort study, we identified 36 consecutive pediatric CDH survivors who underwent cardiopulmonary exercise testing (CPET) and spirometry from 2014 to 2021. Inferential statistics compared survivors with age-, sex-, and size-matched healthy controls; univariate analyses identified factors associated with abnormal testing. RESULTS: Maximal effort CPET and resting spirometry were completed by 27/36 (75%) and 31/36 (86%) subjects, respectively (median age: 8.1 years [interquartile range: 7.5, 10]; 16 females [44%]). Abnormal CPET (percent predicted [pp] peak VO2 < 80%) was more common in the CDH cohort (12 vs. 1, p < 0.001) and associated with longer neonatal intensive care unit (NICU) stay (p = 0.02) and oxygen therapy at discharge (p = 0.03). Exercise impairment was mild (pp peak VO2 70%-80%), moderate (60%-70%), and severe (<60%) in 6, 4, and 2 survivors, respectively. Abnormal spirometry was more common in the CDH cohort (21 vs. 3, p < 0.001; obstructive [n = 15], restrictive [n = 6]) and associated with decreased gestational age (p = 0.046), longer mechanical ventilation in the NICU (p = 0.02), and orthopedic abnormalities (p = 0.03). CONCLUSION(S): Exercise capacity was normal or mildly impaired in most CDH survivors, however, approximately two-thirds demonstrated abnormal spirometry. Impaired exercise capacity and lung function were associated with severity of lung disease postnatally. These data support cardiopulmonary follow-up throughout childhood.
