Cardiac damage staging classification and prognosis in low flow low gradient severe aortic stenosis

Abstract

Abstract Introduction There are currently no established prognostic models for low-flow, low-Gradient (LFLG) severe aortic stenosis (AS). The Cardiac Damage Staging Classification, has been validated as a clinically useful prognostic tool in high-gradient severe AS, but not specifically in LFLG severe AS. Objective To assess and confirm the prognostic utility of the Cardiac Damage Staging Classification, in LFLG severe AS patients. Methods We analysed data from the National Echocardiography Database of Australia (NEDA), a national multicentre registry with individual data linkage to mortality. Of 192,060 adults (aged 62.8±17.8 years) with comprehensive ultrasound profiling of the native aortic valve studied between 2000–2019, 12,013 (6.3%) had severe AS. Based on standard echocardiographic parameters, 611 classical and 959 paradoxical LFLG patients were identified. Mean follow-up was 70±41 months. All-cause and cardiovascular-related mortality were assessed for each LFLG group on an adjusted basis (age and sex), according to cardiac damage classification staging. Results Paradoxical LFLG patients were younger (mean age 74.3 vs 76.2, p=0.006) and more often female (62.8% vs 36.3%, p<0.001). Classical LFLG patients had greater associated cardiac damage at diagnosis (76% vs. 49%, for Stage ≥2, p<0.001). Compared to Stage 0 paradoxical LFLG patients, adjusted 1- and 5-year cardiovascular-related mortality was 200% (HR 2.82, 95% CI 1.12–7.11) and 120% (HR 2.42, 95% CI 1.46–4.02) higher in Stage 2 patients and 350% (HR 4.23, 95% CI 1.68–10.63) and 175% (HR 3.18, 95% CI 1.90–5.34) higher in Stage 3/4 patients, respectively. Compared to Stage 1 classical LFLG patients, adjusted 1- and 5-year cardiovascular-related mortality was 58% (HR 1.66, 95% CI 0.95–2.90) and 24% (HR 1.35, 95% CI 0.91–1.99) higher in Stage 2 patients and 125% (HR 2.48, 95% CI 1.43–4.28) and 52% (HR 1.87, 95% CI 1.26–2.78) higher in Stage 3/4 patients, respectively. Conclusion In patients with LFLG severe AS identified by echocardiography, increasing severity denoted by the cardiac damage staging classification is strongly associated with increasing medium- to long-term mortality. Funding Acknowledgement Type of funding sources: None. Stages + Classical LFLG 5 year mortalityParadoxical LFLG 5 year mortality curves