Club 35 Poster session 2: Thursday 4 December 2014, 08:30-18:00 * Location: Poster area

Introduction: Among patients with unexplained dyspnea, left ventricular (LV) filling pressures (LVFP) is commonly estimated non-invasively by the E/e' ratio using Doppler echocardiography. However the accuracy of E/e' is controversial. We evaluated the correlation of E/e' ratio with invasively measured LVFP and of change in E/e' (ΔE/e') with change in LVFP. Methods: Supine and upright transthoracic echocardiography was performed in patients with unexplained dyspnea undergoing right heart catheterization. Patients with significant valvular disease and reduced LV ejection fraction (LVEF < 50%) were excluded. Pulmonary artery wedge pressure (PAWP) was used as the invasive indicator of LVFP. The mean of septal and lateral e' velocities was used for the calculation of E/e' ratio. Results: We studied 98 subjects with a mean age of 52 ± 20 years (69% of female gender). The supine E/e' and PAWP were 9.2 ± 3.2 and 12.1 ± 4.9 mmHg (range: 4-27 mmHg) respectively and were modestly correlated (r=0.38; p<0.001). With position change (supine to upright), ΔPAWP was -5.1 ± 4.3 mmHg and ΔE/e' was 0.17 ± 2.6, with no significant association between these two measures (r=0.003; p=0.98). Both E-wave (80 ± 22 to 65 ± 22 cm/s) and mean average e' (10.2 ± 3.6 to 7.3 ± 2.0 cm/s) decreased with the upright position. The ΔPAWP was correlated with ΔE-wave velocity (r=0.33; p=0.01), but not with Δe' (r=0.14; p=0.26). Conclusions: In patients with unexplained dyspnea and a preserved LVEF, E/e' is modestly, though significantly, correlated with PAWP. ΔE/e' is not correlated with ΔPAWP, partially related to the preload sensitivity of e'. <fig loc="float" id="CHAPTERsub91065F1"><no>Figure</no><caption> Figure 1 - Supine and delta E/e' plotted </caption> <link locator="15218320140530195032"></fig>