CONGRESS ABSTRACT

Background: The assessment of left ventricular filling pressure (LVFP) is pivotal in patients with Heart Failure with reduced ejection fraction (HFrEF) to guide medical treatment. Non-invasive echocardiography formulas to determine LVFP have been proposed, but all of them lack standardization and they have been mostly applied to HF with preserved ejection fraction populations. In the present study, we evaluated the accuracy of the simplified formula by Lindow et al. in determining the pulmonary capillary wedge pressure (PCWP) compared to the one estimated by right heart catheterization (RHC). Methods: All consecutive HFrEF patients who underwent RHC and echocardiography within 24 hours at our Institution were prospectively enrolled. Non-invasive PCWP was estimated using the formula: 0.230 × left atrial volume index (LAVi) + 10.177 × mitral E – 2.7. Patients were divided into subgroups based on the presence/absence of LA severe dilatation and moderate to severe mitral regurgitation (MR).  The correlation between non-invasive and invasive PCWP was tested in all subgroups. Patients with mitral stenosis, annular calcification (MAC), or prosthetic valves were excluded. Results: 107 patients were included. No significant differences were found between non-invasive PCWP and invasive PCWP in patients without severe LA dilation. (p = 0.084), However, in patients with severe LA dilatation (LAVi >48 ml/m²) non-invasive PCWP significantly overestimated compared to the invasive one (16.52 ± 6.67 mmHg vs 20.92 ± 5.86 mmHg; p < 0.001). Furthermore, non-invasive PCWP was significantly higher compared to invasive PCWP regardless of the MR severity. Overall, non-invasive PCWP was moderately correlated with invasive PCWP (r = 0.43; p < 0.001). However, a strong correlation was observed in patients with LAVi ≤48 ml/m² (r = 0.66; p < 0.001), while no correlation was seen in patients with LAVi >48 ml/m2 (r=0.077; p=0.59), and only a modest correlation was seen in case of moderate-severe MR (r= 0.310). Conclusions: Non-invasive PCWP estimation showed moderate accuracy compared to RHC in determining LVFP in patients with HFrEF. However, in patients with severe LA dilation or moderate-severe MR this formula is not reliable, and alternative methods should be applied.