Purpose. Echocardiography assessment from apical five-chamber view (A5CV) is the standard technique for aortic stenosis (AS) grading. Data on non-apical views, such as right parasternal (RPV), subcostal (SCV) and suprasternal notch (SSNV), is scarce and constitutes the aim of our study. Methods. We designed an observational study that included patients with AS recruited prospectively in whom the stenosis was graded by echocardiography from A5CV and non-apical view. The value of non-apical views in up-grading the stenosis severity (primary objective), the prognostic relevance of such reclassification and the feasibility and reproducibility of non-apical views assessment (secondary objectives) was evaluated. Results. Feasibility of AS appraisal from RPV, SCV and SSNV was 78%, 81% and 56%, respectively (SCV vs SSNV, p = .009). AS were up-graded from non-apical views according to peak gradient, mean gradient, area and indexed area by 24%, 17%, 24% and 22%, respectively (p < .0001). Non-apical views reclassified from non-severe to severe AS, from low gradient severe to high gradient severe AS and from non-critical to critical AS 19%, 23% and 3% of cases (p < .0001). The 4-years hard cardiac events rate was 41% in patients with non-severe AS, 67% in patients with severe AS from non-apical views, 68% in patients with severe AS from A5CV and 80% in patients with severe AS from A5CV and non-apical views (p < .001). Reproducibility of AS evaluation from non-apical views was fair to excellent (intraclass correlation coefficients: SSNV = 0.44, RPV = 0.61, SCV = 0.92). Conclusion. Assessment of AS from non-apical views is feasible, reproducible and valuable over A5CV; its use is encouraged.
Keywords: Aortic stenosis; echocardiography; non-apical echocardiographic views; right parasternal echocardiographic view; subcostal echocardiographic view; suprasternal notch ecocardiographic view.