A Case Based Approach to Calculating Shunts in a PAH Patient with Congenital Heart Disease

The most commonly used method to determine CO is the indirect Fick method (based on assumed rather than directly measured oxygen consumption VO2). In clinical practice, this method of CO determination yield inconsistent measurements in PAH patients and in congenital heart disease (CHD) population referred for RHC. Such possible inconsistencies in hemodynamic assessment may adversely impact clinical assessment and therapeutic decision-making. On the basis of a challenging case of a 42-year-old lady with a patent ductus arteriosus, we describe the approach for complex shunt volume, flows, flow ratio and resistance calculations based on the indirect Fick principle using hemodynamic data obtained in our catheterization laboratory.