Novel algorithm for non-invasive estimation of left atrial pressure in patients with atrial fibrillation

Determining elevated left atrial (LA) pressure is crucial in patients with atrial fibrillation (AF), yet non-invasive estimation using echocardiography remains unclear. This study aimed to identify useful echocardiographic indices for identifying elevated LA pressure in patients with AF.

Patients with paroxysmal or persistent AF referred for catheter ablation at two tertiary hospitals were prospectively enrolled. Mean LA pressure was measured immediately after transseptal puncture. Elevated mean LA pressure was defined as ≥15 mmHg. Transthoracic echocardiography was performed to acquire the guideline-recommended parameters. A total of 176 patients were included, and 63 (36%) patients had a mean LA pressure ≥15 mmHg. Patients with elevated LA pressure had more frequent hypertension, larger LA, higher septal E/e', and worse LA strain than the remaining patients. The correlations between mean LA pressure and each echocardiographic parameter were weak. Septal E/e' ratio showed the best correlation with mean LA pressure (r = 0.351, P < 0.001), and septal E/e' ratio ≥11 was the best parameter (area under the curve = 0.7, sensitivity = 65%, specificity = 73%, accuracy = 70%) to identify elevated mean LA pressure. A hierarchical algorithm consisting of septal E/e' ratio, LA reservoir strain, and LA volume index improved identification of patients with elevated mean LA pressure (sensitivity = 61%, specificity = 91%, accuracy = 80%).

In patients with AF, the septal E/e' ratio was the best single parameter for identifying elevated mean LA pressure. A hierarchical algorithm combining the septal E/e' ratio, LA reservoir strain, and LA volume index helps identify elevated LA pressure in patients with AF.