Application of a Novel Echocardiographic Scoring System to Estimate Left Ventricularfilling Pressure in Aortic Stenosis

Background Despite the increased number of aortic stenosis (AS) patients, non-invasive estimation of the left ventricular (LV) filling pressure (FP) is often challenging partly because of unavailability of E/e' due to the presence of mitral annular calcification (MAC). Recently, an echocardiographic scoring system to estimate LVFP, visually assessed time difference between the mitral valve and tricuspid valve opening (VMT) score was proposed. Because VMT score can be applied for patients with significant MAC, we hypothesized that VMT score could be an alternative parameter of E/e' in AS. Purpose To test whether VMT score could be used as an alternative marker of LVFP to E/e' in AS patients. Methods We enrolled consecutive 116 patients with at least moderate AS in sinus rhythm who underwent right heart catheterization and echocardiography within 7 days. Mean pulmonary artery wedge pressure (PAWP) was measured as invasive parameter of LVFP. LV diastolic dysfunction (DD) was graded according to the ASE / EACVI guidelines. Using two-dimensional echocardiographic images, time sequence of opening of mitral and tricuspid valves was assessed and scored to 0 to 2 (0: tricuspid valve first, 1: simultaneous, 2: mitral valve first). This was based on the phenomenon in which early-diastolic opening of the mitral valve becomes earlier than tricuspid valve with an increase in LV FP and pulmonary artery pressure. When the inferior vena cava was dilated, 1 point was added and VMT score was finally calculated as 0 to 3. Results Overall, PAWP was 12±7 mmHg and elevated (≥15 mmHg) in 29 patients. MAC was observed in 82 patients. Although E/e' was higher in patients with elevated PAWP than in those without (23±11 vs 18±8, P=0.007), its predictive ability to elevated PAWP was non-significant (c-index: 0.59, P=0.13), resulting in low specificity of DD grading to predict elevated LVFP (sensitivity: 79%, specificity: 36%). In contrast, VMT score predicted elevated LVFP with c-index of 0.74 (P<0.001). When VMT score was used instead of E/e', diagnostic accuracy of DD grading was improved (c-index: 0.57 vs 0.82, P<0.001). Conclusion VMT score could be an alternative marker of LVFP to E/e' in AS patients.