Publications by authors named "D Dunbar Ivy"
Background: Right ventricular-arterial coupling (RVAC) describes the relationship between right ventricular contractility and pulmonary vascular afterload. Noninvasive surrogates for RVAC using echocardiographic estimates of right ventricular function, such as tricuspid annular plane systolic excursion (TAPSE), have been shown to correlate with invasively measured RVAC and predict clinical outcomes in pediatric pulmonary arterial hypertension. However, given the limitations of TAPSE at accurately estimating right ventricular function in children, we hypothesized that a multivariable estimate of RVAC using right ventricular free-wall longitudinal strain (RVFW-LS) may perform better than those utilizing TAPSE at predicting clinical outcomes.
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- Pulmonary veno-occlusive disease (PVOD) is a rare pulmonary vascular condition that can be mistaken for pulmonary arterial hypertension (PAH), and they are believed to have different genetic causes.
- This report details a case of a woman diagnosed with PAH at 42, who unfortunately passed away despite treatment, and her son, who was diagnosed with PAH at 16 and required a heart-lung transplant due to worsening conditions.
- The autopsy of the mother showed evidence consistent with PAH, while the son's lung pathology confirmed PVOD, and neither had identifiable genetic mutations linked to these diseases.
The purpose of this study was to investigate neo-aortic curvature and diameter variation using the principal component analysis in patients who underwent a Norwood procedure for hypoplastic left heart syndrome. We further assessed whether neo-aortic curvature and diameter features are associated with clinical outcomes, single right ventricle function and flow hemodynamic patterns derived by 4D-Flow MRI. 55 patients with Fontan circulation who underwent a Norwood procedure in infancy underwent cardiac MRI as part of surveillance of their Fontan circulation.
View Article and Find Full Text PDFObjective: To investigate the feasibility of using actigraphy to measure physical activity (pA) and heart rate variability (HRV) as study endpoints in pediatric pulmonary arterial hypertension (PAH) and to compare their performance to 6-minute-walk distance (6MWD), a common primary endpoint used in PAH clinical trials in adults and children who can walk and understand the test process.
Study Design: We conducted a prospective, multicenter, noninterventional study in pediatric PAH patients and healthy children. Actiheart and Fitbit Charge 2 recorded pA and heart rate data.