Pulmonary valve incompetence. II. Application of electromagnetic flow velocity catheters in children.

During cardiac catheterization in 49 children regurgitant flow through competent and incompetent pulmonary valves was evaluated with electromagnetic flow velocity catheters using the ratio of the separately integrated backward and forward flow velocity signals (vb/vf). When the pulmonary valve was normal, vb/vf was less than or equal to 0.10. After operation for pulmonary valve stenosis or tetralogy of Fallot larger values were often found. In patients with an outflow patch across the pulmonary valve ring vb/vf values of up to 0.54 were found.