Noninvasive Measurement of Pulmonary Artery Pressure in Patients with Fontan Circulation

Background: High pulmonary artery pressure (PAP) due to increased pulmonary vascular resistance is a hallmark of Fontan circulatory failure in univentricular palliation. However, measuring PAP commonly involves invasive methods. This study aimed to evaluate a noninvasive technique to estimate PAP in a cohort of young patients with Fontan circulation and preserved ventricular function using ultrasound imaging and fluoroscopy.

Methods: The collapse point of the internal jugular vein was located by ultrasound in an upright position. Fluoroscopy was subsequently used to locate the pulmonary artery in a lying position. The distance between both points was measured and converted to estimate noninvasive PAP (PAPe). Results were compared with invasive median PAP (PAPi), which was obtained by cardiac catheter examination at the same time.

Results: Nine (3/9 female) subjects with Fontan circulation were enrolled. Median age was 25 (IQR 18–26) years. The systemic ventricle had an LV morphology in 2/9 and an RV morphology in 7/9 subjects. Median arterial oxygen saturation was 93 (IQR 92–95)% while median BNP concentration was 15 (IQR 8–16) pg/mL. Estimated PAPe was higher than invasively measured PAPi (median 11 [IQR 10–13] vs. 9 [IQR 8–13] mm Hg). PAPe was 0 to 3 mm Hg higher than PAPi in 7/9 subjects and lower in 2/9 patients.

Conclusion: The evaluated noninvasive technique to measure PAP was technically feasible. However, obtaining reliable results by noninvasive PAP measurement remains challenging in Fontan patients.

Publication History

Article published online:
11 February 2025