Comparison between characteristics of severe and very severe aortic stenosis.

Objectives: Patients with very severe aortic stenosis (AS) have extremely poor clinical outcomes even if they are asymptomatic compared to those with severe AS, but the clinical and echocardiographic characteristics of patients with very severe AS remain unclear.

Methods: The Asian Valve Registry is a prospective, multicenter, multinational registry for the study and identification of the incidence, natural course, clinical outcomes, and prognostic factors for patients with significant AS at 9 centers in Asian countries. Severe AS was observed in 367 of 1066 patients with AS, and 212 were classified as very severe AS, defined as a peak aortic valve velocity ≥5.0 m/s or a mean aortic valve gradient ≥60 mm Hg.

Results: The prevalence of NYHA functional class II-IV among patients with very severe AS was significantly higher than that among patients with severe AS (67.9% vs 51.5%, P < .001). As for echocardiographic parameters, it was noteworthy that left ventricular mass index (LVMI) and left atrial volume index (LAVI) for patients with very severe AS were significantly larger than those for patients with severe AS (LVMI: 145.1 ± 36.4 g/m vs 119.2 ± 32.1 g/m , P < .0001; LAVI: 56.1 ± 24.6 mL/m vs 49.8 ± 22.6 mL/m , P = .002). Moreover, multivariate logistic regression analysis showed that LVMI was the only independently associated with NYHA functional class II-IV in patients with very severe AS.

Conclusions: Our findings may well have clinical implications for better management of patients with AS and lead to better understanding of poor outcomes for patients with very severe AS.