Cardiac Damage Staging Classification Predicts Prognosis in All the Major Subtypes of Severe Aortic Stenosis: Insights from the National Echo Database Australia

Background: There are currently no established prognostic models for low-gradientsevere aortic stenosis (AS), including those with low-flow, low-gradient (LFLG) or normal-flow, low-gradient (NFLG) severe AS. The cardiac damage staging classificationhas been validated as a clinically useful prognostic tool for high gradient severe AS but not yet for these other common subtypes of severe AS, LFLG and NFLG. Methods: The authors analyzed data from the National Echo Database of Australia, a large national, multicenter registry with individual data linkage to mortality. Of 192,060 adults (mean age, 62.8 +/- 17.8 years) with comprehensive ultrasound profiling of the native aortic valve studied between 2000 and 2019, 12,013 (6.3%) had severe AS. On the basis of standard echocardiographic parameters, 5,601 patients with high gradient, 611 with classical and 959 with paradoxical LFLG, and 911 with NFLG severe AS were identified. Mean follow-up was 88 +/- 45 months. All-cause and cardiovascular-related mortality were assessed for each group on an adjusted basis (age and sex) and analyzed by cardiac damage stage. Results: Patients with LFLG AS had greater associated cardiac damage at diagnosis (stages 3 and 4 in 34% of those with classical LFLG, 22.5% of those with paradoxical LFLG, 15.5% of those with NFLG, and 14% of those with high-gradient AS; P < .001). For all four major subtypes of severe AS, there was a progressive increase in 1-and 5-year mortality with increasing cardiac damage score. For example, for paradoxical LFLG severe AS, compared with stage 0 patients, adjusted 1-year all-cause mortality was 22% higher in stage 1 patients, 55% higher in stage 2 patients (P = .095), and 155% higher in stage 3 and 4 patients (P < .001). Among patients with classical LFLG severe AS, compared with stage 1 patients, adjusted 1-year all-cause mortality was 55% higher in stage 2 patients (P = .018) and 100% higher in stage 3 and 4 patients (P < .001). Conclusions: Regardless of severe AS subtype, increasing severity denoted by the cardiac damage staging classification is strongly associated with increasing mortality risk.

Automated summary

Analysis of data from the National Echo Database of Australia found that regardless of the subtype of severe AS, increasing severity denoted by the cardiac damage staging classification is strongly associated with increasing mortality risk over 1 to 5 years.