Materials and Methods
This study was designed as a retrospective study of patients with and without pulmonary hypertension who had a transthoracic echocardiogram and cardiac catheterization less than 90 days apart. Subjects were identified for the study based on a survey of the EPIC database and Syngodynamics Echocardiographic database (Siemens Medical Solutions, Malvern, PA) for having a history of primary or secondary pulmonary hypertension from 1/1/2007 through 6/1/18. All patients from newborn through 21 years of age were included. Subjects with small intracardiac shunts were included, but subjects with other structural heart defects were excluded. Age matched controls who were undergoing cardiac catheterization for atrial septal defect device closure and had normal pulmonary artery pressures were selected. Echocardiograms were performed within 90 days prior to catheterization. Echocardiograms were reviewed and measured by 2 blinded readers. Studies were assessed for overall quality, presence and velocity of tricuspid regurgitation, pulmonary insufficiency, pulmonary stenosis, peripheral pulmonary artery stenosis, atrial level shunt, ventricular level shunt, and ventricular systolic function. The “septal positional angle” (see figure 1) was made in the parasternal short axis at peak systole at the level of the papillary muscles by drawing a primary midpoint line (M) that bisects the right and left ventricular area equally. A secondary perpendicular line (S) was drawn at the widest dimension of the left ventricle. A third line (A) was drawn which intersected the secondary line at the inferior portion of the left ventricular epicardium and the right ventricular side of the interventricular septum along the midpoint line. The angle (α) was calculated utilizing the angle tool in the Syngodynamics software, from the intersection of the second and third line and defined as the echocardiographically-derived septal positional angle (EDSPA). Data was obtained from the Epic electronic medical record database for these patients including dose and duration of medical therapy, other co-morbidities, and quantitative assessment of right ventricular systolic pressures from cardiac catheterization (RV systolic and diastolic pressures, LV systolic and diastolic pressures, mean pulmonary artery pressure, qualitative ventricular systolic function assessment, Qp:Qs, cardiac index and response to therapy).