Diagnostic Accuracy of the 2016 Guideline-Based Echocardiographic Algorithm to Estimate Invasively-Measured Left Atrial Pressure by Direct Atrial Cannulation.

Background: Although estimation of left ventricular filling pressure (LVFP) using an integrated echocardiographic algorithm is recommended, the usefulness of this algorithm has not been fully validated.

Objectives: The purpose of this study was to investigate the reliability of an algorithmic classification system using invasively measured left atrial pressure (LAP) in a large-scale cohort.

Methods: The authors enrolled 1,967 patients (age 68 ± 10 years) whose LAP was directly measured within the left atrium during catheter ablation for atrial fibrillation. Patients were classified into 3 groups based on the echocardiographic algorithm: normal (group N, n = 1,282), undetermined (group U, n = 160), and elevated (group E, n = 346) LAP groups. Invasively measured LAP and echocardiographic parameters estimating LVFP were compared among the groups.

Results: The median LAP was 12.6 ± 5.7 mm Hg in the entire cohort. LAP was significantly higher in group E than that in the other groups (groups E vs U vs N, 14.2 ± 6.3 mm Hg vs 13.5 ± 5.9 mm Hg vs 12.0 ± 5.5 mm Hg; P < 0.001). Among group E patients, 43.1% had elevated LAP (≥15 mm Hg), whereas 56.9% had normal LAP (<15 mm Hg). Of the patients in group N, 69.0% had normal LAP, whereas 31% had elevated LAP. Although the correlation between invasively measured LAP and E/e', peak tricuspid regurgitant velocity, and left atrial volume index was modest, the number of abnormal values correlated significantly with elevated LAP (P < 0.001).

Conclusions: The classification using combined echocardiographic parameters in the recommendations may be useful for detecting patients with normal LVFP but may be limited for detecting elevated LVFP.