Balancing circulation in congenital heart disease

Description

The heart and lungs cannot be seen as separate entities in cardiac shunt lesions. Blood flow should be balanced between the pulmonary and systemic circulations. CCHD with admixture physiology accounts for nearly 50% of all cyanotic CHD. Proper assessment of hemodynamics  of admixture lesions require SV (mixed venous), pulmonary venous, aortic and PA oxygen saturation and pressures to calculate flows and pulmonary resistance. The aortic saturation reflects the amount of pulmonary blood flow, but streaming is an important component of admixture lesions resulting in minor to significant difference between aortic and PA saturation. In admixture lesions wherein the pulmonary and systemic vascular bed form resistance in parallel, flow into the two vascular beds is determined by the resistance in the two vascular beds and manipulation of individual resistance (systemic or pulmonary) can be used therapeutically to optimize cardiac output and systemic oxygen delivery. This presentation deals with the complexity involved in balancing  the systemic and pulmonary circulation in congenital heart disease.