Real-Time Assessment of Pulmonary Blood Flow in Pulmonary Vein Stenosis Using the Fluoroscopic Flow Calculator

Area of Science:

• Pediatric Cardiology
• Medical Imaging
• Hemodynamics

Background:

• Pulmonary vein stenosis (PVS) in children often leads to restenosis, necessitating vigilant monitoring.
• Current monitoring with lung perfusion scintigraphy (LPS) involves radiation exposure, high costs, and patient discomfort, lacking real-time data.
• There is a need for advanced, real-time methods to assess pulmonary blood flow (Qp) in PVS patients.

Purpose of the Study:

• To evaluate the fluoroscopic flow calculator (FFC) as a real-time tool for estimating pulmonary blood flow (Qp) distribution.
• To assess the potential of FFC to replace or complement lung perfusion scintigraphy (LPS) in pediatric PVS patients.
• To determine the accuracy of FFC in estimating Qp distribution during cardiac catheterization.

Main Methods:

• A retrospective cross-sectional study analyzed data from 18 pediatric PVS patients undergoing cardiac catheterization.
• Right ventricular angiograms were analyzed using the FFC tool to estimate Qp distribution.
• FFC Qp predictions were compared against LPS measurements using median absolute error and Bland-Altman analysis.

Main Results:

• The FFC tool demonstrated accurate Qp distribution predictions with a median absolute error of 3%.
• In 76% of cases, FFC-predicted flow split was within 5% of LPS measurements; all cases were within 7%.
• Bland-Altman analysis showed minimal bias (+0.3%) and no systematic bias at flow extremes.

Conclusions:

• The fluoroscopic flow calculator (FFC) is a promising tool for real-time Qp distribution estimation in pediatric PVS patients.
• FFC may serve as a valuable alternative or adjunct to LPS during cardiac catheterization.
• Further research is recommended to refine FFC, incorporating segmental lung data and validating its real-time application.