Abstract 20168: Right Ventricular Stroke Work Correlates With Outcomes in Pediatric Pulmonary Arterial Hypertension (PAH) Patients
Introduction: Pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary artery pressures and pulmonary vascular resistance. As no definitive treatment options exist, and lung transplant also carries significant mortality rates, optimizing treatment strategies and timing for transplant remains crucial; a quantitative measure to predict disease progression would be greatly beneficial in treatment planning.
Hypothesis: We hypothesize that right ventricular (RV) stroke work correlates with clinical worsening in PAH patients.
Methods: Pediatric patients (<18 years) with idiopathic PAH or PAH secondary to congenital heart diseases with serial, matched catheterization and magnetic resonance imaging (MRI) data were included. RV and PA hemodynamics were numerically simulated by a lumped parameter (circuit analogy) model to create patient-specific pressure-volume (PV) loops not easily replicated clinically. The model was tuned using optimization techniques to match patient-specific MRI and cath-derived RV volumes and pressures for each time point. RV stroke work was calculated from the corresponding PV loop.
Results: Eighteen patients (male: 9, average age: 9.7 years, range: 4.4-16.3 years, average follow-up: 3.9 years, range: 1.1-8.0) were enrolled. Nine patients were clinically stable during the duration of study, the remaining 9 had clinical worsening, defined by either death (n=3) or advanced disease in which IV prostacyclin was used and heart/lung transplant was indicated (n=6). Stroke work for the group with worsening symptoms/disease was significantly larger than the stable group (3430.8±930.7 vs 2029±533.9, p<0.001). Stroke work for patients in NYHA class II/III was also elevated compared to patients in class I (3087.2±963.0 vs 1739.4±566.5, p<0.0001).
Conclusion: RV stroke work correlates with symptomatic/disease worsening in pediatric PAH. Larger studies are required to validate and refine the predictive models.
Author Disclosures: W. Yang: None. A.L. Marsden: None. M.T. Ogawa: None. K.K. Phillips: None. M. Rabinovitch: None. J.A. Feinstein: None.
- © 2016 by American Heart Association, Inc.