Assessment of left ventricular filling pressure with Doppler velocities across the patent foramen ovale

Background: The utility of Doppler velocities across the patent foramen ovale (PFO) to estimate left ventricular (LV) filling pressure is not well known. Methods: The best cut-off value of peak interatrial septal velocity across a transeptal puncture site measured by transesophageal echocardiography for estimating high mean left atrial (LA) pressure (≥ 15 mmHg) was determined in 17 patients. This cut-off value was subsequently applied to 67 patients with a PFO undergoing transthoracic echocardiography (TTE) for assessing the value of PFO velocity in determining LV filling pressure. Results: The peak systolic interatrial septal velocities significantly correlated with directly measured mean LA pressures during transcatheter mitral valve procedure (r = 0.77, P < 0.001). The best cut-off value was 1.7 m/s for predicting high LA pressure (AUC 0.91; sensitivity 90%, specificity 86%). When this cut-off was applied to patients undergoing TTE, peak PFO velocity ≥ 1.7 m/s correlated with reduced e′, higher E/e′, and higher tricuspid regurgitation velocity (P < 0.01). LV filling pressure according to the 2016 diastolic guideline was compared with peak PFO velocity in 51 patients. Among patients with high filling pressure according to the guidelines (n = 20), peak PFO velocity ≥ 1.7 m/s was present in 60% of patients. In patients with normal filling pressure per the guidelines (n = 31), PFO velocity < 1.7 m/s was present 84%. Sensitivity and specificity were 75% and 92%, respectively, in patients with sinus rhythm, but were only 50% and 57%, respectively, among patients with atrial fibrillation. Conclusions: Doppler-derived peak PFO velocities could be valuable in the assessment of increased LV filling pressure using 1.7 m/s as the cut-off value.